CHAPTER 3
Financial Statement Analysis, Planning, and Growth Multiple Choice Questions:
I. DEFINITIONS
LONG-TERM PLANNING
c 1. One key reason a long-term financial plan is develope
d is because:
a. the plan determines your financial policy.
b. the plan determines your investment policy.
c. there are direct connections between achievable corporate growth and the financial
policy.
d. there is unlimited growth possible in a well-developed financial plan.
e. None of the above.
PRO FORMA STATEMENTS
b 2. Projected future financial statements are called:
a. plug statements.
b. pro forma statements.
c. reconciled statements.
d. aggregated statements.
e. none of the above.
PERCENTAGE OF SALES
e 3. The percentage o
f sales method:
a. requires that all accounts grow at the same rate.
b. separates accounts that vary with sales and those that do not vary with sales.
c. allows the analyst to calculate how much financing the firm will need to support the
predicted sales level.
d. Both A and B.
e. Both B and C.
COMMON-SIZE STATEMENTS
e 4. A _____ standardizes items on the income statement and balance sheet as a percentage
of total sales and total assets, respectively.
a. tax reconciliation statement
b. statement of standardization
c. statement of cash flows
d. common-base year statement
e. common-size statement
FINANCIAL RATIOS
a 5. Relationships determined from a firm’s financial information and used for comparison
purposes are known as:
a. financial ratios.
b. comparison statements.
c. dimensional analysis.
d. scenario analysis.
e. solvency analysis.
SHORT-TERM SOLVENCY RATIOS
c 6. Financial ratios that measure a firm’s ability to pay its bills over the short run without
undue stress are known as _____ ratios.
a. asset management
b. long-term solvency
c. short-term solvency
d. profitability
e. market value
CURRENT RATIO
b 7. The current ratio is measured as:
a. current assets minus current liabilities.
b. current assets divided by current liabilities.
c. current liabilities minus inventory, divided by current assets.
d. cash on hand divided by current liabilities.
e. current liabilities divided by current assets.
QUICK RATIO
d 8. Th
e quick ratio is measured as:
a. current assets divided by current liabilities.
b. cash on hand plus current liabilities, divided by current assets.
c. current liabilities divided by current assets, plus inventory.
d. current assets minus inventory, divided by current liabilities.
e. current assets minus inventory minus current liabilities.
CASH RATIO
e 9. The cash ratio is measured as:
a. current assets divided by current liabilities.
b. current assets minus cash on hand, divided by current liabilities.
c. current liabilities plus current assets, divided by cash on han
d.
d. cash on hand plus inventory, divided by current liabilities.
e. cash on hand divided by current liabilities.
LONG-TERM SOLVENCY RATIOS
b 10. Ratios that measure a firm’s financial leverage are known as _____ ratios.
a. asset management
b. long-term solvency
c. short-term solvency
d. profitability
e. market value
TOTAL DEBT RATIO
a 11. The financial ratio measured as total assets minus total equity, divided by total assets, is
the:
a. total debt ratio.
b. equity multiplier.
c. debt-equity ratio.
d. current ratio.
e. times interest earned ratio.
DEBT-EQUITY RATIO
c 12. The debt-equity ratio is measure
d as total:
a. equity minus total debt.
b. equity divided by total debt.
c. debt divided by total equity.
d. debt plus total equity.
e. debt minus total assets, divided by total equity.
EQUITY MULTIPLIER
e 13. The equity multiplier ratio is measured as total:
a. equity divided by total assets.
b. equity plus total debt.
c. assets minus total equity, divided by total assets.
d. assets plus total equity, divided by total debt.
e. assets divided by total equity.
TIMES INTEREST EARNED RATIO
c 14. The financial ratio measure
d as earnings befor
e interest and taxes, divided by interest
expense is the:
a. cash coverage ratio.
b. debt-equity ratio.
c. times interest earned ratio.
d. gross margin.
e. total debt ratio.
CASH COVERAGE RATIO
a 15. The financial ratio measured as earnings before interest and taxes, plus depreciation,
divided by interest expense, is the:
a. cash coverage ratio.
b. debt-equity ratio.
c. times interest earned ratio.
d. gross margin.
e. total debt ratio.
ASSET MANAGEMENT RATIOS
a 16. Ratios that measure how efficiently a firm uses its assets to generate sales are known as
_____ ratios.
a. asset management
b. long-term solvency
c. short-term solvency
d. profitability
e. market value
INVENTORY TURNOVER
c 17. The inventory turnover ratio is measure
d as:
a. total sales minus inventory.
b. inventory times total sales.
c. cost of goods sold divided by inventory.
d. inventory times cost of goods sold.
e. inventory plus cost of goods sold.
DAYS’ SALES IN INVENTORY
e 18. The financial ratio days’ sales in inventory is measured as:
a. inventory turnover plus 365 days.
b. inventory times 365 days.
c. inventory plus cost of goods sold, divided by 365 days.
d. 365 days divided by the inventory.
e. 365 days divided by the inventory turnover.
RECEIVABLES TURNOVER
b 19. The receivables turnover ratio is measured as:
a. sales plus accounts receivable.
b. sales divided by accounts receivable.
c. sales minus accounts receivable, divided by sales.
d. accounts receivable times sales.
e. accounts receivable divided by sales.
DAYS’ SALES IN RECEIVABLES
d 20. Th
e financial ratio days’ sales in receivables is measured as:
a. receivables turnover plus 365 days.
b. accounts receivable times 365 days.
c. accounts receivable plus sales, divided by 365 days.
d. 365 days divided by the receivables turnover.
e. 365 days divided by the accounts receivable.
TOTAL ASSET TURNOVER
b 21. The total asset turnover ratio is measured as:
a. sales minus total assets.
b. sales divided by total assets.
c. sales times total assets.
d. total assets divided by sales.
e. total assets plus sales.
PROFITABILITY RATIOS
d 22. Ratios that measur
e how efficiently a firm’s management uses its assets and equity to
generate bottom line net income are known as _____ ratios.
a. asset management
b. long-term solvency
c. short-term solvency
d. profitability
e. market value
PROFIT MARGIN
a 23. The financial ratio measured as net income divided by sales is known as the firm’s:
a. profit margin.
b. return on assets.
c. return on equity.
d. asset turnover.
e. earnings before interest and taxes.
RETURN ON ASSETS
b 24. The financial ratio measured as net income divided by total assets is known as the
firm’s:
a. profit margin.
b. return on assets.
c. return on equity.
d. asset turnover.
e. earnings before interest and taxes.
RETURN ON EQUITY
c 25. The financial ratio measure
d as net incom
e divided by total equity is known as the
firm’s:
a. profit margin.
b. return on assets.
c. return on equity.
d. asset turnover.
e. earnings before interest and taxes.
PRICE-EARNINGS RATIO
d 26. Th
e financial ratio measured as the price per share o
f stock divided by earnings per
share is known as the:
a. return on assets.
b. return on equity.
c. debt-equity ratio.
d. price-earnings ratio.
e. Du Pont identity.
MARKET-TO-BOOK RATIO
e 27. The market-to-book ratio is measured as:
a. total equity divided by total assets.
b. net income times market price per share of stock.
c. net income divided by market price per share of stock.
d. market price per share of stock divided by earnings per shar
e.
e. market value of equity per share divided by book value of equity per share.
DU PONT IDENTITY
a 28. The _____ breaks down return on equity into three component parts.
a. Du Pont identity
b. return on assets
c. statement of cash flows
d. asset turnover ratio
e. equity multiplier
EXTERNAL FUNDS NEEDED
c 29. The External Funds Neede
d (EFN) equation does not measures the:
a. additional asset requirements given a change in sales.
b. additional total liabilities financing raised given the change in sales.
c. rate of return to shareholders given the change in sales.
d. net income expected to be earned given the change in sales.
e. None of the above.
SUSTAINABLE GROWTH RATE
e 30. To calculate sustainable growth rate, the analyst needs the:
a. profit margin.
b. payout ratio.
c. debt-to-equity ratio.
d. asset requirement ratio.
e. All of the above.
GROWTH
b 31. Growth can be reconciled with the goal of maximizing firm value:
a. because greater growth always adds to value.
b. because growth must be an outcome of decisions that maximize NPV.
c. because growth and wealth maximization are the same.
d. because growth of any type cannot decrease valu
e.
e. none of the above.
SUSTAINABLE GROWTH
b 32. Sustainable growth can be determined by the:
a. profit margin, total asset turnover and the price to earnings ratio.
b. profit margin, the payout ratio, the debt-to-equity ratio, and the asset requirement ratio.
c. Total growth less capital gains growth.
d. Either A or B.
e. None of the above.
SUSTAINABLE GROWTH
c 33. Which of the following will increase sustainable growth?
a. Buy back existing stock.
b. Decrease debt.
c. Increase profit margin.
d. Increase asset requirement ratio.
e. Increase dividend payout ratio.
LONG TERM PLANNING
d 34. Th
e main objective o
f long-term financial plannin
g models is to:
a. determine the asset requirements given the investment activities of the firm.
b. plan for contingencies or uncertain events.
c. determine the external financing needs.
d. all of the above are correct.
e. none of the above are correct.
COMMON-SIZE BALANCE SHEET
d 35. On a common-siz
e balance sheet, all _____accounts are shown as a percentage of:
a. income; total assets.
b.liability; net income.
c.asset; sales.
d.liability; total assets.
e.equity; sales.
RATIO ANALYSIS
a 36. Which one of the following statements is correct concerning ratio analysis?
a. A single ratio is often computed differently by different individuals.
b.Ratios do not address the problem of size differences among firms.
c.There is only a very limited number of ratios which can be used for analytical purposes.
d.Each ratio has a specific formula that is used consistently by all analysts.
e.Ratios can not be used for comparison purposes over periods of time.
LIQUIDITY RATIOS
a 37. Which of the following are liquidity ratios?
I.cash coverage ratio
II.current ratio
III.quick ratio
IV.inventory turnover
a. II and III only
b. I and II only
c. II, III, and IV only
d.I, III, and IV only
e.I, II, III, and IV
LIQUIDITY RATIOS
c 38. An increase in which one of the following accounts increases a firm’s current ratio
without affecting its quick ratio?
a. accounts payable
b. cash
c. inventory
d. accounts receivable
e. fixed assets
LIQUIDITY RATIOS
b 39. A supplier, who requires payment within ten days, is most concerned with which
one of the following ratios when granting credit?
a. current
b.cash
c.debt-equity
d.quick
e.total debt
LONG-TERM SOLVENCY RATIOS
d 40. A firm has a total debt ratio of .47. This means that that firm has 47 cents in debt for
every:
a. $1 in equity.
b. $1 in total sales.
c. $1 in current assets.
d.$.53 in equity.
e.$.53 in total assets.
LONG-TERM SOLVENCY RATIOS
d 41. Th
e long-term debt ratio is probably o
f most interest to a firm’s:
a. credit customers.
b.employees.
c.suppliers.
d.mortgage holder.
e.shareholders.
LONG-TERM SOLVENCY RATIOS
e 42. A banker considering loaning a firm money for ten years would most likely prefer the
firm have a debt ratio of _____ and a times interest earned ratio of_____ .
a. .75; .75.
b..50; 1.00.
c..45; 1.75.
d..40; 2.50.
e..35; 3.00.
LONG-TERM SOLVENCY RATIOS
b 43. From a cash flow position, which one of the following ratios best measures a firm’s
ability to pay the interest on its debts?
a. times interest earned ratio
b.cash coverage ratio
c.cash ratio
d.quick ratio
e.interval measure
ASSET MANAGEMENT RATIOS
a 44. The higher the inventory turnover measure, the:
a. faster a firm sells its inventory.
b.faster a firm collects payment on its sales.
c.longer it takes a firm to sell its inventory.
d.greater the amount of inventory held by a firm.
e.lesser the amount of inventory held by a firm.
ASSET MANAGEMENT RATIOS
d 45. Which on
e o
f the followin
g statements is correct if a firm has a receivables turnover
measure of 10?
a. It takes a firm 10 days to collect payment from its customers.
b.It takes a firm 36.5 days to sell its inventory and collect the payment from the sale.
c.It takes a firm 36.5 days to pay its creditors.
d.The firm has an average collection period of 36.5 days.
e.The firm has ten times more in accounts receivable than it does in cash.
ASSET MANAGEMENT RATIOS
d 46. A total asset turnover measur
e o
f 1.03 means that a firm has $1.03 in:
a. total assets for every $1 in cash.
b.total assets for every $1 in total debt.
c.total assets for every $1 in equity.
d.sales for every $1 in total assets.
e.long-term assets for every $1 in short-term assets.
PROFITABILITY RATIOS
c 47. Puffy’s Pastries generates five cents of net income for every $1 in sales. Thus,
Puffy’s has a _____ of 5 percent.
a. return on assets
b.return on equity
c.profit margin
d.Du Pont measure
e.total asset turnover
PROFITABILITY RATIOS
a 48. If a firm produces a 10 percent return on assets and also a 10 percent return on
equity, then the firm:
a. has no debt of any kind.
b.is using its assets as efficiently as possible.
c.has no net working capital.
d.also has a current ratio of 10.
e.has an equity multiplier of 2.
PROFITABILITY RATIOS
c 49. If shareholders want to know how much profit a firm is making on their entire
investment in the firm, the shareholders should look at the:
a. profit margin.
b.return on assets.
c.return on equity.
d.equity multiplier.
e.earnings per share.
PROFITABILITY RATIOS
a 50. BGL Enterprises increases its operating efficiency such that costs decrease while sales
remain constant. As a result, given all else constant, the:
a. return on equity will increase.
b. return on assets will decrease.
c. profit margin will decline.
d. equity multiplier will decreas
e.
e. price-earnings ratio will increase.
PROFITABILITY RATIOS
d 51. Th
e only d ifference between Joe’s and Moe’s is that Joe’s has old, fully depreciated
equipment. Moe’s just purchased all new equipment which will be depreciated over
eight years. Assuming all else equal:
a. Joe’s will have a lower profit margin.
b. Joe’s will have a lower return on equity.
c. Moe’s will have a higher net income.
d. Moe’s will have a lower profit margin.
e. Moe’s will have a higher return on assets.
MARKET VALUE RATIOS
e 52. Last year, Alfred’s Automotive had a price-earnings ratio o
f 15. This year, the price
earnings ratio is 18. Based on this information, it can be stated with certainty that:
a. the price per share increased.
b. the earnings per share decreased.
c. investors are paying a higher price for each share of stock purchase
d.
d. investors are receiving a higher rate of return this year.
e. either the price per share, the earnings per share, or both changed.
MARKET VALUE RATIO
b 53. Turner’s Inc. has a price-earnings ratio of 16. Alfred’s Co. has a price-earnings ratio of
19. T hus, you can state with certainty that one share of stock in Alfred’s:
a. has a higher market price than one share of stock in Turner’s.
b. has a higher market price per dollar of earnings than does one share of Turner’s.
c. sells at a lower price per s hare than one share of Turner’s.
d. represents a larger percentage of firm ownership than does one share of Turner’s stock.
e. earns a greater profit per share than does one share of Turner’s stock.
MARKET VALUE RATIOS
b 54. Which two of the following are most apt to cause a firm to have a higher price-earnings
ratio?
I. slow industry outlook
II. high prospect of firm growth
III. very low current earnings
IV. investors with a low opinion of the firm
a. I and II only
b. II and III only
c. II and IV only
d. I and III only
e. III and IV only
MARKET VALUE RATIOS
d 55. Vinnie’s Motors has a market-to-book ratio of 3. Th
e book value per share is $4.00.
This means that a $1 increase in the book value per share will:
a. cause the accountants to increase the equity of the firm by an additional $2.
b. increase the market price per share by $1.
c. increase the market price per share by $12.
d. tend to cause the market price per share to ris
e.
e. only affect book values but not market values.
MARKET VALUE RATIOS
d 56. Which on
e o
f the followin
g sets of ratios applies most directly to shareholders?
a. return on assets and profit margin
b.quick ratio and times interest earned
c.price-earnings ratio and debt-equity ratio
d.market-to-book ratio and price-earnings ratio
e.cash coverage ratio and times equity multiplier
DU PONT IDENTITY
b 57. The three parts of the Du Pont identity can be generally described as:
I. operating efficiency, asset use efficiency and firm profitability.
II. financial leverage, operating efficiency and asset use efficiency.
III. the equity multiplier, the profit margin and the total asset turnover.
IV. the debt-equity ratio, the capital intensity ratio and the profit margin.
a. I and II only
b. II and III only
c. I and IV only
d. I and III only
e. III and IV only
DU PONT IDENTITY
e 58. I
f a firm decreases their operatin
g costs, all else constant, then:
a. the profit margin increases while the equity multiplier decreases.
b. the return on assets increases while the return on equity decreases.
c. the total asset turnover rate decreases while the profit margin increases.
d. both the profit margin and the equity multiplier increas
e.
e. both the return on assets and the return on equity increase.
EVALUATING FINANCIAL STATEMENTS
b 59. Which one of the following statements is correct?
a. Book values should always be given precedence over market values.
b. Financial statements are frequently the basis used for performance evaluations.
c. Historical information has no value when predicting the future.
d. Potential lenders place little value on financial statement information.
e. Reviewing financial information over time has very limited value.
EVALUATING FINANCIAL STATEMENTS
c 60. It is easier to evaluate a firm using their financial statements when the firm:
a. is a conglomerate.
b. is global in nature.
c. uses the same accounting procedures as other firms in their industry.
d. has a different fiscal year than other firms in their industry.
e. tends to have one-time events such as asset sales and property acquisitions. EVALUATING FINANCIAL STATEMENTS
a 61. Which two of the following represent the most effective methods of
directly evaluating the financial performance of a firm?
I. comparing the current financial ratios to those of the same firm from prior time
periods
II. comparing a firm’s financial ratios to those of other firms in the firm’s peer
group who have similar operations
III. comparing the financial statements of the firm to the financial statements of similar firms operating in other countries
IV. comparing the financial ratios of the firm to the average ratios of all firms located in the same geographic area
a. I and II only
b. II and III only
c. III and IV only
d. I and IV only
e. I and III only
EVALUATING FINANCIAL STATEMENTS
e 62. Which o
f the followin
g represent problems encountered when comparing the financial
statements of one firm with those of another firm?
I. Either one, or both, of the firms may be conglomerates and thus have unrelated lines of
business.
II. The operations of the two firms may vary geographically.
III. The firms may use differing accounting methods for inventory purposes.
IV. The two firms may be seasonal in nature and have different fiscal year ends.
a. I and II only
b. II and III only
c. I, III, and IV only
d. I, II, and III only
e. I, II, III, and IV
EXTERNAL FUNDS NEEDED
b 63. In the financial planning model, external funds needed (EFN) is equal to changes in
a. assets - (liabilities – equity).
b. assets - (liabilities + equity).
c. (assets + liabilities. – equity).
d. (assets + equity. – liabilities).
e. assets - equity.
SUSTAINABLE GROWTH RATE
e 64. A firm's sustainable growth rate in sales does not directly depend on its
a. debt to equity ratio.
b. profit margin.
c. dividend policy.
d. asset efficiency.
e. all of the above.
SUSTAINABLE GROWTH RATE
a 65. The sustainable growth rate will be equivalent to the internal growth rate when:
a. a firm has no debt.
b. the growth rate is positive.
c. the plowback ratio is positive but less than 1.
d. a firm has a debt-equity ratio exactly equal to 1.
e. net income is greater than zero.
SUSTAINABLE GROWTH RATE
b 66. The sustainable growth rate:
a. assumes there is no external financing of any kind.
b. is normally higher than the internal growth rate.
c. assumes the debt-equity ratio is variable.
d. is based on receiving additional external debt and equity financing.
e. assumes that 100 percent of all income is retained by the firm.
SUSTAINABLE GROWTH RATE
d 67. If a firm bases its growth projection on th
e rate o
f sustainable growth, and shows
positive net income, then the:
a. fixed assets will have to increase at the same rate, regardless of the current capacity
level.
b. number of common shares outstanding will increase at the same rate of growth.
c. debt-equity ratio will have to increase.
d. debt-equity ratio will remain constant while retained earnings increas
e.
e. fixed assets, debt-equity ratio, and number of common shares outstanding will all
increase.
SUSTAINABLE GROWTH RATE
d 68. Marcie’s Mercantil
e wants to maintain their current dividend policy, which is a payout
ratio of 40 percent. The firm does not want to increase their equity financing but are
willing to maintain their current debt-equity ratio. Given these requirements, the
maximum rate at which Marcie’s can grow is equal to:
a. 40 percent of the internal rate of growth.
b. 60 percent of the internal rate of growth.
c. the internal rate of growth.
d. the sustainable rate of growth.
e. 60 percent of the sustainable rate of growth.
FINANCIAL PLANNING MODELS
e 69. One o
f the primary weaknesses of many financial plannin
g models is that they:
a. rely too much on financial relationships and too little on accounting relationships.
b. are iterative in nature.
c. ignore the goals and objectives of senior management.
d. are based solely on best case assumptions.
e. ignore the size, risk, and timing of cash flows.
FINANCIAL PLANNING
d 70. Financial planning, when properly executed,
a. ignores the normal restraints encountered by a firm.
b. ensures that the primary goals of senior management are fully achieved.
c. reduces the necessity of daily management oversight of the business operations.
d. helps ensure that proper financing is in place to support the desired level of growth.
e. eliminates the need to plan more than one year in advance.
III. PROBLEMS
COMMON-SIZE STATEMENTS
b 71. A firm has sales of $1,200, net income of $200, net fixed assets of $500, and current
assets of $300. The firm has $100 in inventory. What is the common-size statement
value of inventory?
a. 8.3 percent
b. 12.5 percent
c. 20.0 percent
d. 33.3 percent
e. 50.0 percent
COMMON-SIZE STATEMENTS
a 72. A firm has sales of $1,500, net income of $100, total assets of $1,000, and total equity
of $700. Interest expense is $50. What is the common-size statement value of the
interest expense?
a. 3.3 percent
b. 5.0 percent
c. 7.1 percent
d. 16.7 percent
e. 50.0 percent
LIQUIDITY RATIOS
b 73. Jessica’s Boutique has cash of $50, accounts receivable of $60, accounts payable of
$200, and inventory of $150. What is the value of the quick ratio?
a. .30
b. .55
c. .77
d. 1.30
e. 1.82
LONG-TERM SOLVENCY RATIOS
a 74. A firm has a debt-equity ratio of .40. What is the total debt ratio?
a. .29
b. .33
c. .67
d. 1.40
e. 1.50
LONG-TERM SOLVENCY RATIOS
e 75. A firm has total debt o
f $1,200 and a debt-equity ratio of .30. What is the value of the
total assets?
a. $1,560
b. $3,000
c. $3,600
d. $4,000
e. $5,200
LONG-TERM SOLVENCY RATIOS
d 76. A firm has sales of $3,600, costs of $2,800, interest paid of $100, and depreciation of
$400. The tax rate is 34 percent. What is the value of the cash coverage ratio?
a. 2
b. 4
c. 6
d. 8
e. 10
LONG-TERM SOLVENCY RATIOS
d 77. Rosita’s Resources paid $250 in interest and $130 in dividends last year. Th
e times
interest earned ratio is 3.8 and the depreciation expense is $60. What is the value of the
cash coverage ratio?
a. 2.40
b. 3.52
c. 3.80
d. 4.04
e. 4.28
ASSET MANAGEMENT RATIOS
c 78. Mario’s Home Systems has sales of $2,800, costs of goods sol
d of $2,100, inventory of
$500, and accounts receivable of $400. How many days, on average, does it take
Mario’s to sell their inventory?
a. 65.2 days
b. 85.2 days
c. 86.9 days
d. 96.9 days
e. 117.3 days
ASSET MANAGEMENT RATIOS
d 79. Syed’s Industries has accounts receivabl
e o
f $700, inventory of $1,200, sales of
$4,200, and cost of g oods sold of $3,400. How long does it take Syed’s to both sell
their inventory and then collect the payment on the sale?
b. 146 days
c. 163 days
d. 190 days
e. 211 days
ASSET MANAGEMENT RATIOS
b 80. A firm has net working capital of $400, net fixed assets of $2,400, sales of $6,000, and
current liabilities of $800. How many dollars worth of sales are generated from every
$1 in total assets?
a. $1.33
b. $1.67
c. $1.88
d. $2.33
e. $2.50
PROFITABILITY RATIOS
b 81 Rosita’s Resta urante has sales of $4,500, total debt of $1,300, total equity of $2,400,
and a profit margin of 5 percent. What is the return on assets?
a. 5.00 percent
b. 6.08 percent
c. 7.39 percent
d. 9.38 percent
e. 17.31 percent
PROFITABILITY RATIOS
c 82. L ee Sun’s has sales of $3,000, total assets of $2,500, an
d a profit margin of 5 percent.
The firm has a total debt ratio of 40 percent. What is the return on equity?
a. 6 percent
b. 8 percent
c. 10 percent
d. 12 percent
e. 15 percent
MARKET VALUE RATIOS
d 83. Jupiter Explorers has $6,400 in sales. Th
e profit margin is 4 percent. There are 6,400
shares of stock outstanding. The market price per share is $1.20. What is the price-
earnings ratio?
a. 13
b. 14
c. 21
d. 30
e. 48
MARKET VALUE RATIOS
c 84. Patti’s has net income of $1,800, a price-earnings ratio of 12, an
d earnings per shar
e of
$1.20. How many shares of stock are outstanding?
a. 1,200
b. 1,400
c. 1,500
d. 1,600
MARKET VALUE RATIOS
d 85. A firm has 5,000 shares of stock outstanding, sales of $6,000, net incom
e o
f $800, a
price-earnings ratio of 10, and a book value per share of $.50. What is the market-to-
book ratio?
a. 1.6
b. 2.4
c. 3.0
d. 3.2
e. 3.6
DU PONT IDENTITY
c 86. Frederico’s has a profit marg in of 6 percent, a return on assets of 8 percent, an
d an
equity multiplier of 1.4. What is the return on equity?
a. 6.7 percent
b. 8.4 percent
c. 11.2 percent
d. 14.6 percent
e. 19.6 percent
DU PONT IDENTITY
d 87. Samuelson’s has a debt-equity ratio of 40 percent, sales of $8,000, net incom
e o
f $600,
and total debt of $2,400. What is the return on equity?
a. 6.25 percent
b. 7.50 percent
c. 9.75 percent
d. 10.00 percent
e. 11.25 percent
DU PONT IDENTITY
a 88. A firm has a return on equity of 15 percent. The debt-equity ratio is 50 percent. The
total asset turnover is 1.25 and the profit margin is 8 percent. The total equity is
$3,200. What is the amount of the net income?
a. $480
b. $500
c. $540
d. $600
e. $620
The following balance sheet and income statement should be used for questions #89 through #94:
Windswept, Inc.
2005 Income Statement
($ in millions)
Net sales $8,450
Less: Cost of goods sold 7,240
Less: Depreciation 400
Earnings before interest and taxes 810
Less: Interest paid 70
Taxable Income $ 740
Less: Taxes 259
Net income $ 481
Windswept, Inc.
2004 and 2005 Balance Sheets
($ in millions)
2004 2005 2004 2005 Cash $ 120 $ 140 Accounts payable $1,110 $1,120 Accounts rec. 930 780 Long-term debt 840 1,210 Inventory 1,480 1,520 Common stock 3,200 3,000 Total $2,530 $2,440 Retained earnings 530 710 Net fixed assets 3,150 3,600
Total assets $5,680 $6,040 Total liabilities & equity $5,680 $6,040 LIQUIDITY RATIOS
a 89. What is the quick ratio for 2005?
a. .82
b. .95
c. 1.36
d. 2.18
e. 2.28
ASSET MANAGEMENT RATIOS
b 90. What is the days’ sales in receivables? (use 2005 values.
a. 31.8 days
b. 33.7 days
c. 38.4 days
d. 41.9 days
e. 47.4 days
FINANCIAL LEVERAGE RATIOS
a 91. What is the equity multiplier for 2005?
a. 1.6
b. 1.8
c. 2.0
d. 2.3
e. 2.5
FINANCIAL LEVERAGE RATIOS
d 92. What is th
e cash coverage ratio for 2005?
a. 11.6
b. 12.8
c. 13.7
d. 17.3
e. 18.8
PROFITABILITY RATIOS
c 93. What is the return on equity for 2005?
a. 5.7 percent
b. 6.8 percent
c. 13.0 percent
d. 15.3 percent
e. 16.0 percent
PROFITABILITY RATIOS
d 94. Windswept, Inc. has 90 million shares of stock outstanding. Their price-earnings ratio
for 2005 is 12. What is the market price per share of stock?
a. $57.12
b. $59.94
c. $62.82
d. $64.13
e. $65.03
The following balance sheet and income statement should be used for questions #95 through #99:
Bayside Inc.
2005 Income Statement
($ in thousands)
Net sales $5,680
Less: Cost of goods sold 4,060
Less: Depreciation 420
Earnings before interest and taxes 1,200
Less: Interest paid 30
Taxable Income $1,170
Less: Taxes 410
Net income $ 760
Bayside, Inc.
2004 and 2005 Balance Sheets
($ in thousands)
2004 2005 2004 2005 Cash $ 70 $ 180 Accounts payable $1,350 $1,170 Accounts rec. 980 840 Long-term debt 720 500 Inventory 1,560 1,990 Common stock 3,200 3,500 Total $2,610 $3,010 Retained earnings 940 1,200 Net fixed assets 3,600 3,360
Total assets $6,210 $6,370 Total liabilities & equity $6,210 $6,370 ASSET MANAGEMENT RATIOS
e 95. How many days on average does it take Bayside to sell their inventory? (Use 2005
values)
a. 126.1 days
b. 127.9 days
c. 153.8 days
d. 176.5 days
e. 178.9 days
FINANCIAL LEVERAGE RATIOS
c 96. What is the debt-equity ratio for 2005?
a. 22.5 percent
b. 26.2 percent
c. 35.5 percent
d. 45.1 percent
e. 47.7 percent
FINANCIAL LEVERAGE RATIOS
c 97. What is the times interest earne
d ratio for 2005?
a. 30
b. 36
c. 40
d. 50
e. 54
FINANCIAL LEVERAGE RATIOS
b 98. What is the equity multiplier for 2005?
a. 1.21
b. 1.36
c. 1.44
d. 1.82
e. 1.91
PROFITABILITY RATIOS
a 99. What is the return on equity for 2005?
a. 16.2 percent
b. 20.9 percent
c. 21.7 percent
d. 22.1 percent
e. 23.3 percent
SUSTAINABLE GROWTH AND DU PONT IDENTITY
c 100. The Green Giant has a 5 percent profit margin an
d a 40 percent dividend payout ratio.
The total asset turnover is 1.40 and the equity multiplier is 1.50. What is the sustainable
rate of growth?
a. 6.30 percent
b. 6.53 percent
c. 6.72 percent
d. 6.80 percent
e. 6.83 percent
INTERNAL GROWTH RATE
c 101. Neal’s Nails has an 11 percent return on ass ets an
d a 30 percent dividend payout ratio.
What is the internal growth rate?
a. 7.11 percent
b. 7.70 percent
c. 8.34 percent
d. 8.46 percent
e. 11.99 percent
INTERNAL GROWTH RATE
a 102. Katelyn’s Kites has net income of $240 and total equity of $2,000. The debt-equity
ratio is 1.0 and the plowback ratio is 40 percent. What is the internal growth rate?
a. 2.46 percent
b. 3.00 percent
c. 4.92 percent
d. 5.88 percent
e. 6.00 percent
IV. ESSAYS
103. Why is it important for managers to understand the importance of both the internal and the sustainable rates of growth?
One reason that causes firms to go out of business is the lack of external funding to support the growth of the firm. Understanding the implications of both the internal and sustainable growth rates can help management know when to limit firm growth such that the growth does not exceed the availability of the necessary financing to fund that growth. SUSTAINABLE GROWTH
104. State the assumptions that underlie the sustainable growth rate and interpret what the sustainable growth rate means.
The usual assumptions are: Costs and assets increase proportionately with sales, the
dividend payout ratio is fixed (or is given), the current debt-equity ratio is optimal, and no new equity sales are possible. The sustainable growth rate is the maximum rate at which sales can increase with the restriction that no new equity sales are possible and long-term debt increases only in an amount that keeps the debt-equity ratio fixed.
NEGATIVE EFN
105. Suppose a firm calculates its external funding needs and finds that it is negative. What are the firm’s options in this case?
With a negative external financing need, the firm has a surplus of funds that it can use to reduce current liabilities, reduce long-term debt, buy back common stock, or increase
dividends. If acceptable opportunities exist, firms might also use the extra funds to add
assets.
COMMON SIZE STATEMENTS
106. Robert Morris Associates publishes peer group financial information for a host of industries, yet the numbers typically only appear in common-size form. Why not report average dollar amounts instead?
The common-size numbers are inherently more useful since they can be directly compared to the financial statements of any firm. If average dollar figures were presented, these numbers would have to be converted to common-size numbers to facilitate comparisons. Plus, since RMA also publishes average sales and average total assets, the user can always work
backwards to figure out the dollar amounts represented by each category.
L6203直流电机控制驱动器 【简要说明】 一、尺寸：长66mmX宽33mm X高28mm 二、主要芯片：L6203 三、工作电压：控制信号直流4.5~5.5V;驱动电机电压7.2~30V 四、可驱动直流（7.2~30V之间电压的电机） 五、最大输出电流4A 六、最大输出功率20W 七、特点：1、具有信号指示 2、转速可调 3、抗干扰能力强 4、具有续流保护 5、可单独控制一台直流电机 6、PWM脉宽平滑调速（可使用PWM信号对直流电机调速） 7、可实现正反转 8、此驱动器非常时候控制飞思卡尔智能车，驱动器压降小，电流大，驱动能力强。【标注图片】
直流电机的控制实例 使用驱动器可以控制一台直流电机。电机分别为OUT1和OUT2。输入端EN可用于输入PWM脉宽调制信号对电机进行调速控制。（如果无须调速可将EN使能端，接高低电平，高电平启动，低电平停止。也可由单片机输出直接控制）实现电机正反转就更容易了，输入信号端IN1接高电平输入端IN2接低电平，电机正转。（如果信号端IN1接低电平，IN2接高电平，电机反转。）可参考下图表： 直流电机测试程序 【原理图】
【测试程序】 /******************************************************************** 汇诚科技 实现功能:调试程序 使用芯片：AT89S52 或者 STC89C52 晶振：11.0592MHZ 编译环境：Keil 作者：zhangxinchun 淘宝店：汇诚科技 *********************************************************************/ #include
多普康微数控 TC8642 两相混合式步进电机驱动器说明书 北京多普康自动化技术有限公司扫一扫，加关注！掌握最新资讯，最新优惠！了解更多成功案例！ 免费热线：4006-033-880 官网：https://www.doczj.com/doc/de6779822.html, 淘宝旗舰店：https://www.doczj.com/doc/de6779822.html,/ 阿里巴巴品牌工业城：https://www.doczj.com/doc/de6779822.html,/
一、概述 TC8642型细分型两相混合式步进电机驱动器，采用直流18～50V供电，适合驱动电压24V～50V，电流小于4.0A外径42～86毫米的两相混合式步进电机。此驱动器采用全数字电流环进行细分控制，电机的转矩波动小，低速运行平稳，振动和噪音低。高速时可输出相对较高的力矩，定位精度高。广泛适用于雕刻机、数控机床、包装机械、传动设备等分辩率要求较高的设备上。 1、主要特点 ●平均电流控制，两相正弦电流驱动输出 ●直流18～50V供电 ●光电隔离信号输入/输出 ●有过压、欠压、过流、相间短路保护功能 ●十六档细分和自动半流功能 ●八档输出相电流设置 ●具备脱机功能 ●启动转速高 ●高速力矩大 2、电气参数 输入电压直流24～50V输入 输入电流小于4安培 输出电流 1.0A～4.2A 功耗功耗：80W；内部保险：6A 温度工作温度-10～45℃；存放温度-40℃～70℃ 湿度不能结露，不能有水珠 气体禁止有可燃气体和导电灰尘 重量200克 二、控制信号接口 图1是驱动器的接线原理图 1、控制信号定义 PLS/CW+：步进脉冲信号输入正端或正向步进脉冲信号输入正端 PLS/CW-：步进脉冲信号输入负端或正向步进脉冲信号输入负端 DIR/CCW+：步进方向信号输入正端或反向步进脉冲信号输入正端 DIR/CCW-：步进方向信号输入负端或反向步进脉冲信号输入负端 ENA+：脱机使能复位信号输入正端
L297+L298步进电机驱动控制板说明书 一、板子跳线器说明:所有跳线都在左边，则由单片机控制。 1、靠近光偶的短路冒打在CLK-555方向时有板上的555提供时钟给驱动器；打在CLK-CP U时右用户CPU提供时钟给驱动器。 2、JT5打在右边：297的HALF/FULL（全速/半速）脚接GND了默认为FULL模式了；JT5打在左边：297的HALF/FULL脚空了电机模式用户自己控制。 3、JT6打在右边：297的CW/CCW脚（方向）接GND了默认为顺时针转动模式了；JT6打在左边：297的CW/CCW脚空了电机正反转模式用户自己控制。 二、按键说明: 板子使用全新的L297作为控制芯片 L298作为驱动芯片板载NE555时钟电路为L297提供CLK因此该版在不需要外部控制的情况下就可以工作板载3个控制按键EN - 使能 CW - 反向旋转 HF - 半速旋转 通过按键就可以直接控制电机的正反转、全速/半速和使能。 三、基本功能描述: 通过光藕隔离之后将CLK CW HF EN四个基本控制端引出单片机等可以非常方便的控制电路的工作这个板子改进的地方比较多也方便研究使用。板子使用1N5822快速二极管作为续流器件其速度要远远快于整流桥的 L298和电机能够提供更完善的有效的保护。模块供电+ 5V(L297和L298控制供电) +12V(根据电机最低4V最高16V)给电机供电。 电机输出接口包括: +12V 四相输出 GND(请根据您的电机连接)。 控制输入接口包括: GND CLK EN CW HF。 EN:高电平停止，低电平使能。 RET:高电平停止，低电平使能。 C/CW:高电平逆时针，低电平顺时针。 H/HD:高电平全速，低电平半速。 CLK：时钟脉冲。 需要特别说明的是:为了测试方便在板子上设置了NE555构成的一个低频时钟源（使用时跳线冒打在CLK-555处），当您使用外部的时钟信号控制电机的转速时必须跳线冒打在CLK -CPU处否则外部时钟是不会传到L297里面。
步进电机,伺服电机可编程控制器KH-01使用说明 一、系统特点 ●控制轴数：单轴； ●指令特点：任意可编程（可实现各种复杂运行：定位控制和非定位控制）； ●最高输出频率：40KHz(特别适合控制细分驱动器)； ●输出频率分辨率：1Hz； ●编程条数：99条； ●输入点：6个（光电隔离）； ●输出点：3个（光电隔离）； ●一次连续位移范围：—7999999~7999999； ●工作状态：自动运行状态，手动运行状态，程序编辑状态，参数设定状态； ●升降速曲线：2条（最优化）； ●显示功能位数：8位数码管显示、手动/自动状态显示、运行/停止状态显示、步数/计数值/程序显示、编辑程序，参数显示、输入/输出状态显示、CP脉冲和方向显示； ●自动运行功能：可编辑，通过面板按键和加在端子的电平可控制自动运行的启动和停止； ●手动运行功能：可调整位置（手动的点动速度和点动步数可设定）； ●参数设定功能：可设定起跳频率、升降速曲线、反向间隙、手动长度、手动速度、中断跳转行号和回零速度； ●程序编辑功能：可任意插入、删除可修改程序。具有跳转行号、数据判零、语句条数超长和超短的判断功能； ●回零点功能：可双向自动回到零点； ●编程指令：共14条指令； ●外操作功能：通过参数设定和编程，在(限位A)A操作和(限位B)B操作端子上加开关可执行外部中断操作； ●电源：AC220V（电源误差不大于±15%）。
一、前面板图 前面板图包括： 1、八位数码管显示 2、六路输入状态指示灯 3、三路输出状态指示灯 4、 CP脉冲信号指示灯
5、 CW方向电平指示灯 6、按键：共10个按键，且大部分按键为复合按键，他们在不同状态表示的功能不同，下面的说明中，我们只去取功能之一表示按键。 后面板图及信号说明： 后面板图为接线端子，包括： 1、方向、脉冲、+5V为步进电机驱动器控制线，此三端分别连至驱动器的相应端，其中： 脉冲————步进脉冲信号 方向————电机转向电平信号 +5V————前两路信号的公共阳端 CP、CW的状态分别对应面板上的指示灯 2、启动：启动程序自动运行，相当于面板上的启动键。 3、停止：暂停正在运行的程序，相当于面板上的停止键，再次启动后，程序继续运行。 4、 (限位A)A操作和(限位B)B操作是本控制器的一大特点：对于步进电机，我们一般进行定量定位控制，如控制电机以一定的速度运行一定的位移这种方式很容易解决，只需把速度量和位移量编程即可。但还有相当多的控制是不能事先定位的，例如控制步进电机从起始点开始朝一方向运行，直到碰到一行程开关后停止，当然再反向运行回到起始点。再例如要求步进电机在两个行程开关之间往复运行n次，等等。在这些操作中，我们事先并不知道步进电机的位移量的具体值，又应当如何编程呢？本控制器利用：“中断操作”，我们称之为“(限位A)A操作”和“(限位B)B操作”。以“(限位A)A操作”为例，工作流程为：当程序在运行时，如果“(限位A)A 操作”又信号输入，电机作降速停止，程序在此中断，程序记住了中断处的座标，程序跳转到“(限位A)A操作”入口地址所指定的程序处运行程序。 5、输入1和输入2通过开关量输入端。 6、输出1、输出2和输出3通过开关量输出端。 7、+24V、地—输入输出开关量外部电源，本电源为DC24V/0.2A,此电源由控制器内部隔离提供。 8、 ~220V控制器电源输入端。 输入信号和输出信号接口电路： 本控制器的“启动”、“停止”、“(限位A)A操作”、“(限位B)B操作”、“输入1”、“输入2”为输入信号，他们具有相同的输入接口电路。“输出1”、“输出2”、“输出3”称为输出信号。他们具有相同的输出接口电路。输入和输出电路都有光电隔离，以保证控制器的内部没有相互干扰，控制器内部工作电源(+5V)和外部工作电源（+24V）相互独立，并没有联系，这两组电源由控制器内部变压器的两个独立绕组提供。 开关量输入信号输出信号的状态，分别对应面板上的指示灯。对于输入量，输入低电平（开关闭合时）灯亮，反之灯灭；对于输出量，输出0时为低电平，指示灯灭，反之灯亮。 开关量输入电路：
L297 L298步进电机驱动控制板说明书 一、板子跳线器说明: 1、靠近光偶的短路冒打在CLK-555方向时有板上的555提供时钟给驱动器；打在CLK-CP U时右用户CPU提供时钟给驱动器。 2、JT5打在右边：297的HALF/FULL（全速/半速）脚接GND了默认为FULL模式了；JT5打在左边：297的HALF/FULL脚空了电机模式用户自己控制。 3、JT6打在右边：297的CW/CCW脚（方向）接GND了默认为顺时针转动模式了；JT6打在左边：297的CW/CCW脚空了电机正反转模式用户自己控制。 二、按键说明: 板子使用全新的L297作为控制芯片 L298作为驱动芯片板载NE555时钟电路为L297提供CLK因此该版在不需要外部控制的情况下就可以工作板载3个控制按键EN - 使能 CW - 反向旋转 HF - 半速旋转 通过按键就可以直接控制电机的正反转、全速/半速和使能。 三、基本功能描述: 通过光藕隔离之后将CLK CW HF EN四个基本控制端引出单片机等可以非常方便的控制电路的工作这个板子改进的地方比较多也方便研究使用。板子使用1N5822快速二极管作为续流器件其速度要远远快于整流桥的 L298和电机能够提供更完善的有效的保护。模块供电+ 5V(L297和L298控制供电) +12V(根据电机最低4V最高16V)给电机供电。 电机输出接口包括: +12V 四相输出 GND(请根据您的电机连接)。 控制输入接口包括: GND CLK EN CW HF。 需要特别说明的是:为了测试方便在板子上设置了NE555构成的一个低频时钟源（使用时跳线冒打在CLK-555处），当您使用外部的时钟信号控制电机的转速时必须跳线冒打在CLK -CPU处否则外部时钟是不会传到L297里面。 四、接口说明: 1、板子左上方小二接口(JT1) VCC接+5V、GND接电源地，次处为芯片L297和555芯片的工作电压；
YKD3422MA 数字式细分驱动器 特点木工雕刻机 数控机床 包装设备 纺织设备 水钻设备 激光切割机 YKD3422MA是一款基于高性能DSP控制的三相步进电机驱动器，硬件设计上采用DSP+IPM模块进行高集成度简约化设计，数字式PWM控制方式，软件上采用矢量控制技术及微细分自适应控制技术，即使在低细分条件下也可以使电机低速运行平稳，几乎没有震动和噪音，电机在高速时力矩大大高于两相和五相混合式步进电机。驱动电压为交流110V-240V，适配电流在4.2A以下的各种型号三相混合式步进电机。此款驱动最适宜控制高电压小电流电机。定位精度最高可达10000步/转.细分设置更改需要断电重启后才生效，运行电流及抱轴电流设定支持不断电在线设置。 电流设定驱动器接线示意图 典型应用概述1. STOP/Im为保持状态(或抱轴状态)输出电流设置电位器，可设置为 正常输出电流的20%-80%(顺时针增大,逆时针减小)，支持在线调整。 2. RUN/Im为正常工作输出电流设置开关(详见下表)，支持在线调整。 PU DR MF DIP开关设定输入信号波形时序图安装尺寸(单位:mm)◆◆◆◆◆◆◆◆◆◆◆◆ 采用矢量控制及微细分控制技术,在运行平稳性、噪音、震动、发热等方面 较传统驱动器均有较大的提升； 衰减模式及衰减时间自适应控制，开关管运行在最少开关模式，运行时发热 大大降低,电流波形失真度较小; 设有16档等角度恒力矩细分,最高分辨率10000步/转； 最高响应频率可达200Kpps; 加减速曲线配置合适的情况下电机最高空载速度可达50R/S(or 3000RPM); 步进脉冲停止超过100ms时,线圈电流自动减为20%-80%(由STOP/Im设定) 光电隔离信号输入/输出 驱动电流从0.6A/相到4.2A/相分16档可调 单电源输入，电压范围：交流AC110-220V 出错保护：过热保护/过流、电压过低保护 YKD3422MA体积为178x108.5x68()，净重量为：0.93kg 相位记忆功能(注：输入脉冲停止超过5秒后，驱动器自动记忆当时电机相位， 重新上电或MF信号由有效变为无效时，驱动器自动恢复电机相位)。 3mm 注意！信号端DB15塑料壳 需保留45mm的安装空间。
` 基于L297系列芯片的步进电机驱动器 设计说明书 一：概述 步进电动机是用脉冲信号进行控制，将点脉冲信号转换成相应的角位移和线位移的微电机，广泛地应用于打印机等办公知道设备以及各种控制装置。 步进电机和一般的电机不同，之接电源步进电机不能转动，而每加一个点脉冲仅转动一定的角度，另外，改变脉冲的频率时，步进电机的速率也跟着改变。 步进电机按电磁转距产生机理的不同可以分为反应式步进电机，永磁式步进电机和混合式步进电机，而按绕组的相数又可以分为单相，两相，三相。五相……… 二：步进电机的驱动方式 由于篇幅有限和设计的实际情况，在这我只介绍和设计方式相关的二相步进电机的励磁方式和驱动方式。 （一）驱动器结构简介 步进电机驱动器主要结构可以由下图表示 各部分的主要作用为 1：环行分配器：根据输入信号的要求产生电机在不同状态下的开关波形 2：信号处理：对环行分配器产生的开关信号波形进行PWM调制以及对相关的波形进行滤波整形处理 3：推动级：对开关信号的电压，电流进行放大提升 4：主开关电路：用功率元器件直接控制电机的各相绕组 5：保护电路：当绕组电流过大时产生关断信号对主回路进行关断，以保护电机驱动器和电机绕组 6：传感器：对电机的位置和角度进行实时监控，传回信号的产生装置。 （二）：励磁方式
本设计对二相双极性电机进行的，所以介绍二相电机的励磁方式 1：一相励磁：通电的绕组只有一相，依次切换相电流产生旋转步距角为1。8度，对这种励磁方式，每个脉冲到来时的旋转角的响应有振动，若频率过高，有时会产生失步现象 2：两相励磁：两相同时流通电流，也采用依次切换相电流的方法，二相励磁的步距角为1.8度，二相历次的总电流增大2倍，则最高启动频率增大，能获得高的转速，另外，过度性能也好。 3：一，二相励磁：这是一种交替进行一相励磁，二相励磁的方法，启动电流每两个始终切换依次，因此步距角为0。9度，励磁电流变大，过度性能也好，最大启动频率也高。 （三）：驱动方式 单极性和双极性是步进电机最常采用的两种驱动架构。单极性驱动电路使用四颗晶体管来驱动步进电机的两组相位，电机结构则如图1所示包含两组带有中间抽头的线圈，整个电机共有六条线与外界连接。这类电机有时又称为四相电机，但这种称呼容易令人混淆又不正确，因为它其实只有两个相位，精确的说法应是双相位六线式步进电机。六线式步进电机虽又称为单极性步进电机，实际上却能同时使用单极性或双极性驱动电路。 单极性步进电机驱动电路 双极性步进电机的驱动电路则如图2所示，它会使用八颗晶体管来驱动两组相位。双极性驱动电路可以同时驱动四线式或六线式步进电机，虽然四线式电机只能使用双极性驱动电路，它却能大幅降低量产型应用的成本。双极性步进电机驱动电路的晶体管数目是单极性驱动电路的两倍，其中四颗下端晶体管通常是由微控制器直接驱动，上端晶体管则需要成本较高的上端驱动电路。双极性驱动电路的晶体管只需承受电机电压，所以它不像单极性驱动电路一样需要箝位电路。
2H42B 细分步进电机驱动器使用手册 V ersion 2.0 版权所有不得翻印 【使用前请仔细阅读本手册，以免损坏驱动器】 东莞市一能机电技术有限公司 DONGGUAN ICAN－TECH CO.,LTD 地址：东莞市万江区新和工业区瑞联振兴工业园B栋4楼 https://www.doczj.com/doc/de6779822.html,/ Email:tech@https://www.doczj.com/doc/de6779822.html,
2H42B 步进电机驱动器 一、 2H42B 步进电机驱动器产品简介 1.1概述 2H42B 步进电机驱动器是一款高性价比的细分两相步进电机驱动器。最大可提供2.0A 的电流输出。由于采用了双极性恒流斩波控制技术，与市面上同类型步进电机驱动器相比，其对步进电机噪声和发热均有明显改善。适用于尺寸为28，35，39，42等各类2相或4相混合式步进电机，具有体积小，使用简单方便等特点。 1.2特点 ◆低噪声，高速大转矩特性 ◆光电隔离差分信号输入，响应频率最高200K ◆供电电压12VDC-36VDC ◆细分精度1，2，4，8，16，32，64，128， ◆输出电流峰值可达2.0A 倍细分可选 ◆静止时电流自动减半 ◆外形尺寸小（96*60*24mm ） ◆可选择脉冲上升沿或下降沿触发 ◆电流设定方便，八档可选 ◆可驱动4、6、8线二相、四相步进电机 ◆具有过流，过温保护功能 1.3应用领域 适用于各类型自动化设备或仪器，如雕刻机、打标机、切割机、激光照排、绘图仪、数控 机床、机械手，包装机械，纺织机械等，极具性价比和竞争力。 二、 2H42B 步进电机驱动器 电气、机械和环境指标 1 网址:www https://www.doczj.com/doc/de6779822.html, 2.2 2H42B 步进电机驱动器使用环境及参数 图1.安装尺寸图 2.4加强散热方式 1) 2H42B 步进电机驱动器的可靠工作温度通常在60℃以内，电机工作温度为80℃以内； 2) 建议使用时选择自动半流方式 （即电机停止时电流自动减至60% ），以减少电机和驱动器的发热； 3) 安装步进电机驱动器时请采用立式侧面安装，使散热面向易于空气对流的方向，必要时在机箱内靠近驱动器处应安装排气风扇，进行强制散热，从而保证驱动器在可靠工作温度范围内工作。 2 网址: www https://www.doczj.com/doc/de6779822.html,
《电子线路CAD》课程论文题目：电机驱动电路的设计
1 电路功能和性能指标 此电路是用MCU发出的PWM波来控制电机的转速的电路，电路输入电压是7.2V。 2 原理图设计 2.1原理图元器件制作 元器件截图： 图1 这个是图中的BTN7971的原理图，是一款电机驱动半桥芯片。 制作步骤： 1.点击菜单栏的放置，然后点击弹出的窗口中的矩形，如下图： 图2 2.然后鼠标光标下就会出现一个黄色的矩形边框，自己就可以随意设置边框的大小，之后框图的大小可以拖动修改，如下图：
图3 3.框图定好后,点击下图的图标，可以进行画引脚： 图4 4.放引脚时可以按table键设置引脚属性： 图5 2.2 原理图设计 ①原理图设计过程： 首先简历里一个PCB工程项目，保存命名为BTN驱动，然后在这个工程下面
建立一个原理图文件和一个PCB文件，并将其保存并重命名为BTN在与工程相同的目录下面，然后开始绘制原理图了，将所有设置默认为初始状态不需要更改，然后开始画原理图了，将其模块化绘图比较方便好看。 ②下面就是绘制成功后的原理图： 图6 ③下图为massage框图： 图7 其操作步骤为： 1.点击system中的message， 2.然后点击下图中高亮部分 图8
3.最后打开message就可以看见编译信息了 4.之后根据错误提示进行查找修改，直至没有错误和警告，如下图： 图9 ④该项目的元器件库截图如下： 图10 图11
生成原理图库的步骤为： 1.点击界面右下角的design compiler,然后点击如图高亮部分： 图12 2.点击界面上面的工具栏中的设计，然后点击高亮部分： 图13 3.最后可以查看刚才打开的navigater,如图：
TB6560 3A步进电机驱动板说明 功能简介： 1）工作电压直流10V-35V。建议使用开关电源DC24V供电。 2）采用6N137高速光藕，保证高速不失步。 3）采用东芝TB6560AHQ全新原装芯片，内有低压关断、过热停车及过流保护电路，保证最优性能。 4）额定最大输出为：±3A，峰值3.5A。 5) 适合42，57步进3A以内的两相/四相/四线/六线步进电机，不适合超过3A的步进电机。 6）自动半流功能。
7）细分：整步，半步，1/8步，1/16步，最大16细分。 在同类产品中的特色： 1、电流级逐可调，满足你的多种应用需求。 2、自动半流可调。 3、采用6N137高速光藕，保证高速不失步。 4、电流采样电阻采用高精度、大功率电阻，保证电机稳定运行。 5、板印设置说明，不用说明书亦可操作。 6、采用厚密齿散热器，散热良好。 7、整机提供三年质量保证。
产品使用说明： 一、产品简介 1.概述 TB6560步进电机驱动器是由我公司自主研发的一款具有高稳定性、可靠性和抗干扰性的经济型步进电机驱动器，适用于各种工业控制环境。该驱动器主要用于驱动35、39、42、57 型4、6、8线两相混合式步进电机。其细分数有4 种，最大16细分；其驱动电流范围为0.3A－3A，输出电流共有14 档，电流的分辨率约为0.2A；具有自动半流，低压关断、过流保护和过热停车功能。 2.应用领域 适合各种中大型自动化设备，例如：雕刻机、切割机、包装机械、电子加工设备、自动装配设备等。 3.整机介绍 整机介绍主要对驱动器的设置、接口、指示灯及安装尺寸等相关说明。具体说明见下表： 驱动器操作说明 运行电流设置由 SW1－SW3、S1 四个拨码开关来设定驱动器输出电流，其输出电流共有14 档。具体输出电流的设置，请看电路板面版图说明。 停止电流设置用户可通过S2 来设置驱动器的自动半流功能。“1”表示停止电流设为运行电流的20%，“0”表示停止电流设为运行电流的50%。一般用途中应将S2 设成“1”，使得电机和驱动器的发热减少，可靠性提高。 细分设置由 S3－S4 两个拨码开关来设定驱动器细分数，其共有4档细分。用户设定细分时，应先停止驱动器运行。具体细分数的设置，请看电路板面版图说明。
先给大家介绍个技术交流QQ群有什么不能搞好的可以大家交流 28858693 技术交流QQ群 H桥驱动电路原理 2008-09-05 16:11 一、H桥驱动电路 图4.12中所示为一个典型的直流电机控制电路。电路得名于“H桥驱动电路”是因为它的形状酷似字母H。4个三极管组成H的4条垂直腿，而电机就是H中的横杠（注意：图4.12及随后的两个图都只是示意图，而不是完整的电路图，其中三极管的驱动电路没有画出来）。 如图所示，H桥式电机驱动电路包括4个三极管和一个电机。要使电机运转，必须导通对角线上的一对三极管。根据不同三极管对的导通情况，电流可能会从左至右或从右至左流过电机，从而控制电机的转向。 图4.12 H桥驱动电路 要使电机运转，必须使对角线上的一对三极管导通。例如，如图4.13所示，当Q1管和Q4管导通时，电流就从电源正极经Q1从左至右穿过电机，然后再经 Q4回到电源负极。按图中电流箭头所示，该流向的电流将驱动电机顺时针转动。当三极管Q1和Q4导通时，电流将从左至右流过电机，从而驱动电机按特定方向转动（电机周围的箭头指示为顺时针方向）。
图4.13 H桥电路驱动电机顺时针转动 图4.14所示为另一对三极管Q2和Q3导通的情况，电流将从右至左流过电机。当三极管Q2和Q3导通时，电流将从右至左流过电机，从而驱动电机沿另一方向转动（电机周围的箭头表示为逆时针方向）。 图4.14 H桥驱动电机逆时针转动 二、使能控制和方向逻辑 驱动电机时，保证H桥上两个同侧的三极管不会同时导通非常重要。如果三极管Q1和Q2同时导通，那么电流就会从正极穿过两个三极管直接回到负极。此时，电路中除了三极管外没有其他任何负载，因此电路上的电流就可能达到最大值（该电流仅受电源性能限制），甚至烧坏三极管。基于上述原因，在实际驱动电路中通常要用硬件电路方便地控制三极管的开关。 图4.155 所示就是基于这种考虑的改进电路，它在基本H桥电路的基础上增加了4个与门和2个非门。4个与门同一个“使能”导通信号相接，这样，用这一个信号就能控制整个电路的开关。而2个非门通过提供一种方向输人，可以保证任何时候在H桥的同侧腿上都只有一个三极管能导通。（与本节前面的示意图一样，图4.15所示也不是一个完整的电路图，特别是图中与门和三极管直接连接是不能正常工作的。）
TB6600升级版 两相步进驱动器 使用说明书 [使用前请仔细阅读本手册，以免损坏驱动器]
目录 一、产品简介 (3) 概述 (3) 特点 (3) 二、接口和接线介绍 (3) 信号输入端 (3) 电机绕组连接 (3) 电源电压连接 (4) 状态指示 (4) 接线方式 (4) 接线要求 (5) 三、电流、细分拨码开关设定 (5) 细分设定 (5) 工作（动态）电流设定 (6) 四、机械和环境指标 (6) 使用环境及参数 (6) 机械安装图 (7) 五、电机适配 (7) 电机适配 (7) 电机接线 (8) 供电电压和输出电流的选择 (8) 五、常见问题 (9) 应用中常见问题和处理方法 (9) 六、保修条款 (10)
一、产品简介 ◆概述 TB6600升级版驱动器是一款专业的两相混合式步进电机驱动器，可适配国内外各种品牌，电流在4.0A及以下，外径39，42，57mm的四线，六线，八线两相混合式步进电机。适合各种小中型自动化设备和仪器，例如：雕刻机、打标机、切割机、激光照排、绘图仪、数控机床、拿放装置等。在用户期望低成本、大电流运行的设备中效果特性。 ◆特点 ※信号输入：单端，脉冲/方向 ※细分可选：1/2/4/8/16/32细分 ※输出电流：0.5A-4.0A ※输入电压：9-42VDC ※静止时电流自动减半 ※可驱动4,6,8线两相、四相步进电机 ※光耦隔离信号输入，抗干扰能力强 ※具有过热、过流、欠压锁定、输入电压防反接保护等功能 ※体积小巧，方便安装 ※外部信号3.3-24V通用，无需串联电阻 二、接口和接线介绍 ◆信号输入端 PUL+ PUL-脉冲输入信号。默认脉冲上升沿有效。为了可靠响应脉冲信号，脉冲宽度应大于1.2us。 DIR+ DIR-方向输入信号，高/低电平信号，为保证电机可靠换向，方向信号应先于脉冲信号至少5us建立。电机的初始运行方向与电机绕组接线有关，互换任一相绕组（如A+、A-交换）可以改变电机初始运行方向。 ENA+ ENA-使能输入信号（脱机信号），用于使能或禁止驱动器输出。使能时，驱动器将切断电机各相的电流使电机处于自由状态，不响应步进脉冲。当不需用此功能时，使能信号端悬空即可。 ◆电机绕组连接 A+,A-电机A相绕组。 B+,B-电机B相绕组。
第三节步进电动机及其驱动 一、步进电机的特点与种类 1.步进电机的特点 步进电机又称脉冲电机。它是将电脉冲信号转换成机械角位移的执行元件。每当输入一个电脉冲时，转子就转过一个相应的步距角。转子角位移的大小及转速分别与输入的电脉冲数及频率成正比，并在时间上与输入脉冲同步。只要控制输入电脉冲的数量、频率以及电机绕组通电相序即可获得所需的转角、转速及转向。 步进电动机具有以下特点： ?工作状态不易受各种干扰因素(如电压波动、电流大小与波形变化、温度等)的影响； ?步进电动机的步距角有误差，转子转过一定步数以后也会出现累积误差，但转子转过一转以后，其累积误差变为“零” ； ?由于可以直接用数字信号控制，与微机接口比较容易； ?控制性能好,在起动、停止、反转时不易“丢步”； ?不需要传感器进行反馈，可以进行开环控制； ?缺点是能量效率较低。 就常用的旋转式步进电动机的转子结构来说，可将其分为以下三种： （1）可变磁阻(VR-Variable Reluctance),也叫反应式步进电动机 （2）永磁(PM-Permanent Magnet)型 （3）混合(HB-Hybrid)型 （1）可变磁阻(VR-Variable Reluctance) 结构原理：该类电动机由定子绕组产生的反应电磁力吸引用软磁钢制成的齿形转子作步进驱动，故又称作反应式步进电动机。其结构原理如图3.5定子1 上嵌有线圈，转子2朝定子与转子之间磁阻最小方向转动，并由此而得名可变磁阻型。
图3.6 可变式阻步进电机 可变磁阻步进电机的特点： 反应式电动机的定子与转子均不含永久磁铁，故无励磁时没有保持力； 需要将气隙作得尽可能小，例如几个微米； 结构简单，运行频率高，可产生中等转矩，步距角小（0.09~9°） 制造材料费用低； 有些数控机床及工业机器人上使用。 （3）混合(HB-Hybrid)型 结构原理 这类电机是PM式和VR式的复合形式。其定子与VR类似，表面制有小齿，转子由永磁铁和铁心构成，同样切有小齿，为了减小步距角可以在结构上增加转子和定子的齿数。其结构如图3.7所示。 混合式步进电机特点: HB兼有PM和VR式步进电机的特点： 步距角可以做得较小(0.9~3.6°)； 无励磁时具有保持力； 可以产生较大转矩，应用较广。
L298N电机驱动器使用 说明 兴创科技
是ST公司生产的一种高电压、大电流电机驱动芯片。该芯片采用15脚封装。主要特点是：工作电压高，最高工作电压可达46V；输出电流大，瞬间峰值电流可达3A，持续工作电流为2A；额定功率25W。内含两个H桥的高电压大电流全桥式驱动器，可以用来驱动直流电动机和步进电动机、继电器线圈等感性负载；采用标准逻辑电平信号控制；具有两个使能控制端，在不受输入信号影响的情况下允许或禁止器件工作有一个逻辑电源输入端，使内部逻辑电路部分在低电压下工作；可以外接检测电阻，将变化量反馈给控制电路。使用L298N芯片驱动电机，该芯片可以驱动一台两相步进电机或四相步进电机，也可以驱动两台直流电机。 宝贝简介：
一、尺寸：65mmX41mm X28mm 二、主要芯片：L298N、光电耦合器 三、工作电压：控制信号直流~;驱动电机电压5~30V 四、可驱动直流（5~30V之间电压的电机） 五、最大输出电流2A （瞬间峰值电流3A） 六、最大输出功率25W 七、特点： 1、具有信号指示 2、转速可调 3、抗干扰能力强 4、具有续流保护 5、可单独控制两台直流电机 6、可单独控制一台步进电机 7、PWM脉宽平滑调速（可使用PWM信号对直流电机调速） 8、可实现正反转
9、采用光电隔离 实例一：步进电机的控制实例 步进电机是数字控制电机，它将脉冲信号转变成角位移，即给一个脉冲信号，步进电机就转动一个角度，因此非常适合于单片机控制。步进电机可分为反应式步进电机（简称VR）、永磁式步进电机（简称PM）和混合式步进电机（简称HB）。 一、步进电机最大特点是： 1、它是通过输入脉冲信号来进行控制的。 2、电机的总转动角度由输入脉冲数决定。
伺服电机工作原理图 伺服电机工作原理——伺服电机内部的转子是永磁铁，驱动器控制的U/V/W三相电形成电磁场，转子在此磁场的作用下转动，同时电机自带的编码器反馈信号给驱动器，驱动器根据反馈值与目标值进行比较，调整转子转动的角度。 永磁交流伺服系统具有以下等优点：（1）电动机无电刷和换向器，工作可靠，维护和保养简单；（2）定子绕组散热快；(3)惯量小，易提高系统的快速性；（4）适应于高速大力矩工作状态；（5）相同功率下，体积和重量较小，广泛的应用于机床、机械设备、搬运机构、印刷设备、装配机器人、加工机械、高速卷绕机、纺织机械等场合，满足了传动领域的发展需求。 永磁交流伺服系统的驱动器经历了模拟式、模式混合式的发展后，目前已经进入了全数字的时代。全数字伺服驱动器不仅克服了模拟式伺服的分散性大、零漂、低可靠性等确定，还充分发挥了数字控制在控制精度上的优势和控制方法的灵活，使伺服驱动器不仅结构简单，而且性能更加的可靠。现在，高性能的伺服系统，大多数采用永磁交流伺服系统其中包括永磁同步交流伺服电动机和全数字交流永磁同步伺服驱动器两部分。伺服驱动器有两部分组成：驱动器硬件和控制算法。控制算法是决定交流伺服系统性能好坏的关键技术之一，是国外交流伺服技术封锁的主要部分，也是在技术垄断的核心。 2 交流永磁伺服系统的基本结构 交流永磁同步伺服驱动器主要有伺服控制单元、功率驱动单元、通讯接口单元、伺服电动机及相应的反馈检测器件组成，其结构组成如图1所示。其中伺服控制单元包括位置控制器、速度控制器、转矩和电流控制器等等。我们的交流永磁同步驱动器其集先进的控制技术和控制策略为一体，使其非常适用于高精度、高性能要求的伺服驱动领域，还体现了强大的智能化、柔性化是传统的驱动系统所不可比拟的。 目前主流的伺服驱动器均采用数字信号处理器（DSP）作为控制核心，其优点是可以实现比较复杂的控制算法，事项数字化、网络化和智能化。功率器件普遍采用以智能功率模块（IPM）为核心设计的驱动电路,IPM内部集成了驱动电路,同时具有过电压、过电流、过热、欠压等故障检测保护电路,在主回路中还加入软启动电路,以减小启动过程对驱动器的冲击。
步进电机驱动方案概述 众所周知，步进电机的驱动方式有整步，半步，细分驱动。三者即有区别又有联系，目前，市面上很多驱动器支持细分驱动方式。本文主要描述这三种驱动的概述 如下图是两相步进电机的内部定子示意图，为了使电机的转子能够连续、平稳地转动，定子必须产生一个连续、平均的磁场。因为从宏观上看，电机转子始终跟随电机定子合成的磁场方向。如果定子合成的磁场变化太快，转子 跟随不上，这时步进电机就出现失步现象。 既然电机转子是跟随电机定子磁场转动，而电机定子磁场的强度和方向是由定子合成电流决定且成正比。即只要控制电机的定子电流，则可以达到驱动电机的目的。下图是两相步进电机的电流合成示意图。其中Ia是由A-A`相产生，Ib是由B-B`相产生，它们两个合成后产生的电流I就是电机定子的合成电流，它可以代表电机定子产生 磁场的大小和方向。 有了以上的步进电机背景描述后，对于步进电机的整步、半步、细分的三种驱动方式，都会是同一种方法，只是电流把一个圆(360°)分割的粗细程序不同。 整步驱动 对于整步驱动方式，电机是走一个整步，如对于一个步进角是3.6°的步进电机，整步驱动是每走一步是走3.6°。下图是整步驱动方式中，电机定子的电流次序示意图： 由上图可知，整步驱动每一时刻只有一个相通电，所以这种驱动方式的驱动电路可以是很简单，程序代码也是相对容易实现，且由上图可以得到电机整步驱动相序如下： BB’→A’A→B’B→AA’→BB’
下图是这种驱动方式的电流矢量分割图： 可见，整步驱动方式的电流矢量把一个圆平均分割成四份。 下图是整步驱动方式的A、B相的电流I vs T图： 可以看出，整步驱动描出的正弦波是粗糙的。使用这种方式驱动步进电机，低速时电机会抖动，噪声会比较大。但是，这种驱动方式无论在硬件或软件上都是相对简单，从而驱动器制造成本容易得到控制。 半步驱动 对于半步驱动方式，电机是走一个半步，如对于一个步进角是3.6°的步进电机，半步驱动是每走一步，是走 1.8°(3.6°/2)。 下图是半步驱动方式中，电机定子的电流次序示意图： 由上图可见，半步驱动方式的比整步驱动方式相对复杂一些，在同一时刻，可能两个相都需要被通电，如果要求电机转动的力矩平稳，则需要在两相同时通电时，通电电流应该为单相通电电流的sin(45°)，即√2/2。当然，可以直接通以和单相通电流相等的电流，结果是电机转动过程中的力矩不恒定，但它带来的好处是驱动电路或软件编写的简化。具体应用视实际场合而定。以下是这种的驱动方式的驱动相序： BB’→BB’ A’A→A’A→B’B A’A→B’B→B’B AA’→AA’→AA’ BB’
由于本人主要是搞软件的，所以硬件方面不是很了解，但是为了更好地相互学习，仅此整理出一份总结出来，有什么错误的地方还请大家积极的指出！供大家一起参考研究！ 我们做的智能小车，要想出色的完成一场比赛，需要出色的控制策略！就整个智能车这个系统而言，我们的被控对象无外乎舵机和电机两个！通过对舵机的控制能够让我们的小车实时的纠正小车在赛道上的位置，完成转向！当然那些和我一样做平衡组的同学不必考虑舵机的问题！而电机是小车完成比赛的动力保障，同时平衡组的同学也需要通过对两路电机的差速控制，来控制小车的方向！所以选一个好的电机驱动电路非常必要！ 常用的电机驱动有两种方式：一、采用集成电机驱动芯片；二、采用MOSFET和专用栅极驱动芯片自己搭。集成主要是飞思卡尔自己生产的33886芯片，还有就是L298芯片，其中298是个很好的芯片，其内部可以看成两个H桥，可以同时驱动两路电机，而且它也是我们驱动步进电机的一个良选！由于他们的驱动电流较小（33886最大5A持续工作，298最大2A持续工作），对于我们智能车来说不足以满足，但是电子设计大赛的时候可能会用到！所以想要详细了解他们的同学可以去查找他们的数据手册！在此只是提供他们的电路图，不作详细介绍！ 33886运用电路图
下面着重介绍我们智能车可能使用的驱动电路。普遍使用的是英飞凌公司的半桥驱动芯片BTS7960搭成全桥驱动。其驱动电流约43A，而其升级产品BTS7970驱动电流能够达到70几安培！而且也有其可替代产品BTN79 70，它的驱动电流最大也能达七十几安！其内部结构基本相同如下： 每片芯片的内部有两个MOS管，当IN输入高电平时上边的MOS管导通，常称为高边MOS管，当IN输入低电平时，下边的MOS管导通，常称为低边MOS 管；当INH为高电平时使能整个芯片，芯片工作；当INH为低电平时，芯片不工作。其典型运用电路图如下图所示： EN1和EN2一般使用时我们直接接高电平，使整个电路始终处于工作状态！
D306三相混合式步进电机驱动器使用说明 ！阅读 请详细阅读本说明书后，再进行安装连接！ ！！！安全事项 ★严禁带电对驱动器进行任何拔码设置或进行测量！ ★必须在断电三分钟后，接线，安装和拔码设置！ ★二次开关机之间须有三分钟间隔，以免发生故障报警！ ★驱动器的输入电压需满足技术要求！ ★通电前，确定电源电缆，电机动力电缆，信号电缆连接正确，且连接紧固！ ★通电前，电缆连接完毕后，用万用表电阻档测量驱动器A、B、C端子与接地端子之间的电阻应为无穷大。用万用表最小电阻档测量驱动器A、B、C端子每两相电阻值应相等，避免电机相间短路，或电机缺相引起驱动器损坏。 一．性能简介 D306型号三相伺服混合式步进电机驱动器，具有以下特点： 1．采用交流伺服控制原理，在控制方式上增加了全数字式电流环控制，三相正弦电流驱动输出，使三相混合式电机低速无爬行，无共振区，噪音小。 2．驱动器功放级的电压达到DC325伏，步进电机高速运转时仍然有高转矩输出。 3．具备短路、过压、欠压、过热等完善保护功能，可靠性高。 4．具有细分和半流功能。有多种细分选择，最小步距角可设为0.036°。 5．适用面广，通过设置不同相电流可配置各种电机。
三．外观尺寸
2 3。 接口信号说明：CP+/CP-（脉冲信号）：每个脉冲上升沿使电机转动一步，最小脉宽≥2.5μS,最高接收频率200KHz 。 CW+/CW-（方向信号）：单脉冲控制方式时为方向控制信号输入接口，若CW 为低电平，电机顺时针旋转，CW 为高电平，电机逆时针旋转。双脉冲控制方式时为反转步进脉冲信号输入接口。方向信号切换时间≥10μS 。改变电机旋转方向可通过互换电机任意两相接线。 FREE+/FREE-（脱机信号）脱机信号输入接口，脱机+与脱机-之间分别加高低电平，电机无相电流，电机转子处于不稳定的自由状态（脱机状态）；反之脱机+与脱机-之间分别加相同电平和不接，电机处于锁定状态。 Vin 外部电源输入端（仅需接ERR 和FINE 时所需） ERR 报警信号输出接口。 FINE 当FINE 为高电平时，细分功能有效，当FINE 为低电平时，细分功能无效。 当细分功能为无效时，电机每转的脉冲数为细分功能有效时的1/10。 五.拔码开关设置 D306驱动器有一个拔码开关，如图示： 1 2437865 1． 相电流设置 步进电机内部线圈必须接成三角形，驱动器的相电流设置值必须小于或等于电机铭牌上的额定相电注：若电机额定电流标称值是“Y ”接法的电流值时，设定电流值等于额定值的1.7倍。 2. 半流功能设置 半流功能是指输入脉冲频率<800Hz 时输出相电流减小到额定值的60%，可防止电机发热，减小低频振动。通常拔码DIP4设置为OFF ，半流功能有效，当设置为ON 时，半流功能无效。