PSRR测试文档
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145125105856545255O f f s e t V o l t a g e (V )m -55-15525125Temperature (C)°-35456585105ProductFolder Order NowTechnical Documents Tools &SoftwareSupport &CommunityOPA188ZHCSB21B –MARCH 2013–REVISED SEPTEMBER 2016OPA188高精度、低噪声、轨至轨输出、36V 、零漂移运算放大器1特性•低失调电压:25μV (最大值)•零漂移:0.03μV/°C •低噪声:8.8nV/√Hz–0.1Hz 至10Hz 噪声:0.25μV PP •出色的DC 精度:–电源抑制比(PSRR);142dB –共模抑制比(CMRR):146dB –开环路增益:136dB •增益带宽:2MHz•静态电流:510μA (最大值)•宽电源电压:±2V 至±18V •轨至轨输出•输入包括负电源轨•已过滤射频干扰(RFI)的输入•微型尺寸封装2应用•桥式放大器•应力计•传感器应用•温度测量•电子称•医疗仪表•电阻温度检测器3说明OPA188运算放大器采用TI 的专有自动归零技术,以提供低失调电压(最大为25μV )并随时间推移和温度变化而实现接近零漂移的性能。
此高精度低静态电流微型放大器提供高输入阻抗和摆幅为电源轨15mV 之内的轨到轨输出。
输入共模范围包括负电源轨。
单电源或双电源可在4V 至36V (±2V 至±18V )范围内使用。
单通道版本采用微型SOT-23-5、MSOP-8和SO-8封装。
所有版本的额定工作温度范围均为-40°C 至+125°C 。
器件信息(1)器件型号封装封装尺寸(标称值)OPA188SOIC (8) 4.90mm x 3.91mm SOT-23(5) 2.90mm ×1.60mm VSSOP (8)3.00mm ×3.00mm(1)要了解所有可用封装,请参阅数据表末尾的封装选项附录。
ASP环境的测试把IIS和数据库安装好了之后,就是要对IIS进行配置,配置后即可发布ASP网站。
要配置IIS,首先要进入IIS管理器,同安装IIS一样,首先进入【控制面板】,找到【管理工具】,双击打开它,如图1-33所示。
图1-33 进入管理工具要进行IIS的配置,可以按照下面的步骤来:双击【Internet信息服务】,进入如图1-34所示的IIS管理器。
图1-34 IIS管理器在图1-34中,可以看到左边的属性区域是IIS提供的服务,右边视图栏显示的是具体信息。
由于ASP是属于WWW服务,所以只要关心树型结构中的【网站】就可以了。
要进行IIS 的配置,可以通过IIS管理器的菜单栏来进行,也可以通过弹出式菜单来管理。
注意:在IIS提供服务的时候,首先要启动网站服务,则要选中【默认网站】,然后通过工具栏上面的黑色三角形按钮来启动该服务。
启动后,黑色三角按钮失效,此时可以通过“■”按钮来停止服务或者通过“‖”按钮暂停服务。
我们在“默认网站”上单击右键,选择属性选项。
这样就弹出了如图1-35所示的属性对话框。
在属性设置对话框中,可以看到很多属性页,如【网站】、【ISAPI筛选器】、【主目录】、【目录】、【文档】、【目录安全性】、【HTTP头】、【自定义错误】,下面介绍其中重要的属性页。
图1-35 属性页在网站属性页中,最主要的设置是TCP端口的设定。
对于WWW协议而言,默认端口是80。
通常,我们在访问为80端口的Web服务器的时候,只需要输入IP地址或者域名即可。
例如访问“/”。
而如果对方设置的是8080端口的话,则必须采用“:8080”。
这里我们不需要设置任何东西,默认即可。
接下来就是要学习主目录属性页的内容,在图1-35中,选择主目录就进入了,如图1-36所示。
在主目录属性页中,最主要是树型是本地路径的位置,通过改变主目录,可以让网络服务器对应不同的网站内容。
如果主目录设置成“D:\asp”,另外一个路径设置为“E:\Script”。
SpO Pulse Ox Wrist Oximeter Reference DesignTI Reference DesignsTI Reference Designs are mixed-signal solutions created by TI’s experts. Verified Desi gns offer the theory, complete PCB schematic & layout, bill of materials and measured performance of the overall system.Circuit DescriptionPulse oximeters measure arterial blood oxygen saturation by sensing absorption properties of deoxygenated and oxygenated hemoglobin using various wavelengths of light. A basic meter is comprised of a sensing probe attached to a patient's earlobe, toe, finger or other body locations, depending upon the sensing method (reflection or transmission), and a data acquisition system for the calculation and eventually display of oxygen saturation level, heart rate and/or blood flow.This reference design discusses the methodology for achieving a Low Power, Portable Pulse Oximeter.High Performance is achieved by using the AFE4400, a Fully Integrated Analog Front End that consists of a low noise receiver channel with an integrated Analog to Digital Converter, an LED transmit section, diagnostics for sensor and LED fault detection. Additional components are an ultra-low power microcontroller (MCU) for calculating the oxygen saturation, a wireless module based on Bluetooth Low Energy (BLE) for exchanging information with smart phones, tablets or PCs, a motion sensor for monitoring the user’s activity, a sensing probe, ferroelectric RAM (FRAM) for data logging, a lithium-polymer rechargeable battery, a battery charger and a battery fuel gauge.Sensing ProbeBluetooth Low Energy ModuleIn general, Pulse Oximeters require ultra-low power consumption and low noise power rails in order to support extended battery life and precision measurements. TI's buck-boost converters provide support for Li-ion battery technologies and 96% efficiency. For additional low noise power rails, high PSRR LDOs are also available. Requirements for wall-plug and USB-port charging can be addressed with the TI's linear lithium low single-cell charger family. Innovative next-generation gas gauge solutions are offered with "Impedance Track" to automatically learn/detect battery characteristics, extending both battery life and system run time.Design ResourcesDesign Archive (ZIP File) All design filesAFE4400SPO2EVM GUI Product FolderAFE4400Product Folder1.Design SummaryThis design takes a block level approach for designing a low power finger based pulse oximeter.1.1Design GoalProvide a SpO Pulse Ox Wrist Oximeter reference example.2. Theory of Operation2.1 Background on PPG MeasurementsPulse oximetry is based on spectrophotometric measurements of changes in blood color. Oxygenated blood is distinctively red, whereas deoxygenated blood has a characteristic dark blue coloration. The optical property of blood in the visible (i.e. between 400 and 700nm) and near-infrared (i.e. between 700 and 1000nm) spectral regions depends strongly on the amount of O2 carried by blood.The method exploits the fact that Hb has a higher optical absorption coefficient in the red region of the spectrum around 660nm compared with HbO2, as illustrated in Figure 1. On the other hand, in the near-infrared region of the spectrum around 940nm, the optical absorption by Hb is lower compared to HbO2.At the isobestic wavelength (i.e. 805nm), where the two curves cross over, the absorbance of light is independent of oxygenation level.Figure 1 Oxygenated versus de-oxygenated blood light absorption of IR and REDThe absorbance of light at a specific wavelength by a homogenous solution can be accurately determined by the Beer-Lambert’s law, using the following equationwhere is the transmitted light intensity, is the incident light intensity, is the specific absorption coefficient of the sample, is the concentration of the sample, and is the path length of light transmission.In oximetry, it is assumed that a hemolyzed blood sample consists of a two-component homogeneous mixture of Hb and HbO2 and that light absorbance by the mixture of these components is additive. However, other variables in the biological media such as bone, skin, tissue, muscle and blood also scatter light.The absorption of light also depends on both skin thickness and color. Therefore, Beer-Lambert’s Law is unable to account for all of these variables.Modern pulse oximetry relies on the detection of a photoplethysmographic (PPG) signal produced by variations in the quantity of arterial blood associated with periodic contractions and relaxations of the heart.As shown in Figure 2, the magnitude of the PPG signal depends on the amount of blood ejected from the heart with each systolic cycle, the optical absorption of blood, absorption by skin and various tissue components, and the specific wavelengths used to illuminate the vascular tissue bed.During systole, when the arterial pulsation is at its peak, the volume of blood in tissue increases. This additional blood absorbs more light, thus reducing the light intensity which is either transmitted or backscattered.During diastole, less blood is present in the vascular bed, thus increasing the amount of light transmitted or backscattered. The pulsatile part of the PPG signal is considered as the “AC” component, and the non- pulsatile part, resulting mainly from the venous blood, skin and tissue, is referred to as the “DC” component. A deviation in the LED brightness or detector sensitivity can change the intensity of the light detected by the sensor. This dependence on transmitted or backscattered light intensity can be compensated by using a normalization technique where the AC component is divided by the DC component, as given in the equation below:(⁄)Thus, the time invariant absorbance due to venous blood or surrounding tissues does not have any effect on the measurement. This normalization is carried out for both the red (R) and the infrared (IR) wavelengths, as shown in Figure 3. The normalized R/IR “ratio of ratios” can then be related empirically to SpO2, as shown in Figure 4. When the ratio is 1, the SpO2 value is about 85%.Figure 2 Variations in light attenuation by tissue illustrating the rhythmic effect of arterial pulsationFigure 3 Normalization of R and IR wavelengths to remove the effects of variation in the incident light intensity or detector sensitivityMost pulse oximeters measure absorbance at two different wavelengths and are calibrated using data collected from CO-oximeters by empirically looking up a value for SpO2, giving an estimation of SaO2 using the empirical relationship given by the equationwhere is based on a normalization where the pulsatile (AC) component is divided by the corresponding non-pulsatile (DC) component for each wavelength, and and are linear regression coefficients which are related to the specific absorptions coefficients of Hb and HbO2.The constants and are derived empirically during in-vivo calibration by correlating the ratio calculated by the pulse oximeter against SaO2 from arterial blood samples by an in vitro oximeter for a large group of subjects. Pulse oximeters read the SaO2 of the blood accurately enough for clinical use under normal circumstances because they use a calibration curve based on empirical data shown in figure 4.Figure 4 Empirical relationship between arterial SaO2 and normalized (R/IR) ratio2.2 Hardware overview and circuit descriptionThe key components required for acquiring and signal-conditioning the PPG signals are the LED, photodetector and AFE. Some commercially available AFEs, like TI’s AFE4400,integrate both the LED driver circuitry and the photodiode signal conditioning circuitry in a single package, Figure 5. This new generation of AFEs can drive the LED currents in using an H-bridge configuration capable of driving up to 150 mA/leg, with short-circuit protection. They can also increase the dynamic range greater than 105 dB and create a current reference independent of the IR and red LEDs.Figure 5 Commercially available AFEs like TI’s AFE4400 integrate the LED driver circuitry and the photodiode signal conditioning circuitry in a single packageThe photodiode circuitry embedded into these devices can amplify currents below 1 µA with 13 bits of resolution. It is ultra-low-power (<4 mW) and has a programmable TIA. The AFE consumes less than 3 mA of current when active.2.2.1 LED Transmit SectionAs highlighted in Figure 6, the transmit stage contains two sections: the LED driver and LED current control section.a.LED Driver - There are two LEDs, one for the visible red wavelength and another for the infrared wave length. To turnthem on, an H-Bridge circuit is used. The LED1_ON and LED2_ON signal decide which LED to turn on (the whole circuit is time multiplexed).b.LED Current Control– The current source () locally regulates and ensures that the actual LED current tracks thespecified reference. The LED1 and LED2 reference current can be independently set by Register. The 8-bit current resolution here meets a dynamic range of better than 105dB (based on a 1-sigma LED current noise).c. A Push-Pull LED driver is also supported, please refer to AFE4400 Datasheet for detail.Figure 6 LED Transmit Section2.2.2 Receiver Stage2.2.2.1 I-V Amplifier (Transimpedance Amplifier) and Ambient Cancellation SectionV TIAOUTFigure 7 Receiver Section – Stage 1The RX Stage consists of a differential current-to –voltage transimpedance amplifier that converts the input photodiode current into a appropriated voltage, as shown in Figure 5. The feedback resistor of the amplifier () is programmable to support a wide range of photodiodes currents. (Available values in AFE4400: 1MΩ, 500kΩ, 250kΩ, 100kΩ, 50kΩ, 25kΩ, and 10kΩ)The differential voltage at the TIA output includes the pleth component (the desired signal) and a component resulting from the ambient light leakage:The feedback resistor and feedback capacitor form a low-pass filter for the input signal current. Always ensure that the low-pass filter has sufficiently high bandwidth (as shown by Equation below) because the input current consists of pulses. For this reason, the feedback capacitor is also programmable. (Available value include: 5pF, 10pF, 25pF, 50pF, 100pF and 250pF. Any combination of these capacitors can also be used)The TIA is followed by the second stage, which consists of a current digital-to-analog converter (DAC) that sources the cancellation current and an amplifier that gains up the pleth component alone. The current DAC () has a cancellation current range of 10 uA with 10 steps (1 uA each). The amplifier has five programmable gain settings (): 1, 1.414, 2, 2.828 and 4.The receiver provides digital samples corresponding to ambient duration. The host processor can use these ambient values to estimate the amount of ambient light leakage. The processor must then set the value of the ambient cancellation DAC. Using the set value, the ambient cancellation stage subtracts the ambient component and gains up only the pleth component of the received signal.The differential output of the second stage is :[ ]Where:= 100kΩ,= photodiode current pleth component,= photodiode current ambient component, and= the cancellation current DAC value (as estimated by the host processor).2.2.2.2Filter and Analog-to-Digital ConverterFigure 8 Receiver Section – Stage 2The output of the ambient cancellation amplifier is separated into LED2 and LED1 channels.1)When LED2 is on, the amplifier output is filtered and sampled on capacitor ,2)When LED1 is on, the amplifier output is filtered and sampled on capacitor ,3)In between the LED2 and LED1 pulses, the idle amplifier output is sampled to estimate the ambient signal oncapacitors and .The sampling duration is termed the Rx sample time and is programmable for each signal, independently. The sampling can start after the I-V amplifier output is stable (to account for LED and cable settling times). The Rx sample time is used for all dynamic range calculations; the minimum time supported is 50µs.A single, 22-bit ADC converts the sampled LED2, LED1, and ambient signals sequentially. Each conversion takes 25% of the pulse repetition period and provides a single digital code at the ADC output. Note that four data streams are available at the ADC output (LED2, LED1, ambient LED2, and ambient LED1) at the same rate as the pulse repetition frequency. The ADC is followed by a digital ambient subtraction block that additionally outputs the (LED2–ambientLED2) and (LED1–ambient LED1) data values.2.2.2.3DiagnosticsThe device includes diagnostics to detect open or short conditions of the LED and photo sensor, LED current profile feedback, and cable on or off detection. By default, the diagnostic function takes tDIAG = 8 ms to complete after the DIAG_EN register bit is enabled. The diagnostics module, when enabled, checks for nine types of faults sequentially. The faults are listed below: 2.2.2.4Photodiode-Side Fault DetectionFigure 9 shows the diagnostic for the photodiode-side fault detection.Figure 9 Photodiode Side Fault Detection2.2.2.5Transmitter-Side Fault DetectionFigure 10 shows the diagnostic for the photodiode-side fault detection.Figure 10 Transmitter Fault Detection2.3 MicrocontrollerIn this design example, the microcontroller is used to calculate the heart rate, merge the motion sensor data, and process the AFE information. The microcontroller should have specific features including the ability to maintain the context at all times. It should also have a limited power budget because it will be continuously running and nobody wants to drain the batteries.2.4Motion SensorsSensors are a fundamental part of the human machine interface (HMI). They help the system identify the context and environmental conditions. Motion sensors such as accelerometers, gyroscopes, and magnetometers help identify whether a person is seated, walking, or running. They are key elements to identify the orientation of the arm, wrist, or other specific part of the body where the activity monitor is located.They also help to track the travel distances and provide a more accurate position of the system by increasing the resolution of the GPS with dead-reckoning algorithms.2.5Communication LinkThe system described in this article has both wireless and wired communication links. The wireless communication link is based on BLE and is based on the BR-LE4.0-S2A, an FCC-certified (Federal Communications Commission) system-in-PCB (printed-circuit board) module available online that only requires a few external components.This module works with AT-based commands and is easy to use since it includes a network processor that handles all the transactions required by the Bluetooth 4.0 stack. The wired communication is based on USB 2.0. The microcontroller’s built-in module requires only a few external components. USB is also used for charging the lithium-polymer battery.2.6Battery Charger and Fuel GaugeThe battery charger operates from either a USB port or ac adapter and supports charge currents up to 1.5 A. The input voltage range with input overvoltage protection supports unregulated adapters. The USB input current limit accuracy and startup sequence allow the battery charger to meet the USB-IF inrush current specification. Additionally, the input dynamic power management prevents the charger from crashing incorrectly configured USB sources.The battery fuel gauge circuits an easy-to-configure microcontroller peripheral that provides system-side fuel gauging for single-cell lithium-ion batteries. The device requires minimal user configuration and system microcontroller firmware development. The battery fuel gauge uses the impedance track algorithm for fuel gauging and provides information such as remaining battery capacity (mAh), state-of-charge (%), and battery voltage (mV).3. Verification and measured performance 3.1 Health Hub Demonstration SuiteThe figure below shows up the Health Hub measurement setup hardware description. The app requires a PC, a BlueRadios USB Serial Dongle along with the wrist watch data acquisition system and the sensing probe. The pictured device connects to the app via Bluetooth low energy.Figure 11 Health Hub Measurement Setup Hardware Description3.2 Health Hub App 3.2.1 Interface OverviewHealth Hub is designed to allow the control and display of many BLE enabled health monitoring devices on a single screen. The screen is divided into multiple discrete areas, Figure 12, called Device Controls and each area allows a specific BLE enabled health monitoring device control.3.3 Demonstration usage Terminology:Advertising mode : the Bluetooth radio is broadcasting advertising data; this allows another device to initiate a connection to the advertising device.Device : a piece of hardware required for a demo.Device control : The area on the screen of the app that controls a device.BlueRadios USBSerial DongleWrist Watch Data Acquisition SystemFigure 12 Health Hub PC GUI Interface with highlighted Device Controls3.3.1 Common OperationsCommon operations apply to all of the demos with the Health Hub app.3.3.1.1 Find DevicesThe first step in initiating a connection to a Health Hub demonstration device is to have the PC finding the device. To this end, the desired device must be in advertising mode. Generally the devices will advertise any time they are turned on and not connected. When the Pulse Ox is in advertising mode the green LED D7 on the wrist watch will be flashing. To find a device press the Discover Devices button as shown in the figure below. The icon will change to discovering and will find devices for about ten seconds.Figure 13 PC GUI front panel before and after searching for BLE enabled health monitoring devices3.3.1.2 ConnectionThe second step is to form a connection. Before finding a device by using Discover Devices the device controls appear as in the figure below.Figure 14 BLE enabled device not foundAfter a device has been found the device control will appear as in the figure below.Figure 15 Device found – connection can be establishedWhen the Connect button is pressed a selector will be shown as belowFigure 16 Desired Device selection from the listWhen the desired device is selected from the list, the app will form a connection to the device over Bluetooth low energy. After connection the device control will open fully and control over the device can begin. The solid blue LED labeled D8 indicates the connected state. When the device is reporting periodic data, the blue LED labeled D2 will flash. Periodic data only is used with the Wrist Based HRM device control. When the device is reporting graphic data, the green LED labeled D1 will be on. Live Monitor uses both periodic and graphic data.NOTE if after selecting a device from the selector the device control becomes unavailable, an immediate disconnect has occurred. If this happens repeatedly the devices batteries may be depleted.3.4 Measured ResultsThe watch should be attached comfortably around the user’s wrist. The sensor cable should be connected to the micro USB port next to the on/off switch close to the Texas instruments logo. The sensor should be clipped on one of the user’s fingers.Figure 17 Measurement setupThe following figure shows up some measurement resultsIMPORTANT NOTICETexas Instruments Incorporated and its subsidiaries(TI)reserve the right to make corrections,enhancements,improvements and other changes to its semiconductor products and services per JESD46,latest issue,and to discontinue any product or service per JESD48,latest issue.Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.All semiconductor products(also referred to herein as“components”)are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.TI warrants performance of its components to the specifications applicable at the time of sale,in accordance with the warranty in TI’s terms and conditions of sale of semiconductor products.Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty.Except where mandated by applicable law,testing of all parameters of each component is not necessarily performed.TI assumes no liability for applications assistance or the design of Buyers’products.Buyers are responsible for their products and applications using TI components.To minimize the risks associated with Buyers’products and applications,Buyers should provide adequate design and operating safeguards.TI does not warrant or represent that any license,either express or implied,is granted under any patent right,copyright,mask work right,or other intellectual property right relating to any combination,machine,or process in which TI components or services are rmation published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement e of such information may require a license from a third party under the patents or other intellectual property of the third party,or a license from TI under the patents or other intellectual property of TI.Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties,conditions,limitations,and notices.TI is not responsible or liable for such altered rmation of third parties may be subject to additional restrictions.Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice. 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1 LDO选型关键指标及定义1.1 输入电压范围LDO的输入电压范围决定了最低的可用输入电源电压。
指标可能提供宽的输入电压范围,最小的输入电压VIN必须大于VOUT+VDO。
需要注意,这与器件Datasheet中所给出的输入电压最小值无关。
1.2压差压差指保持电压稳定所需的输入电压和输出电压之间的最小差值。
也就是说,LDO能够在输入电压降低时保持输出负载电压不变,直到输入电压接近输出电压加上压差,在这个点输出电压将“失去”稳定。
压差应尽可能小,以使功耗最小,效率最高。
当输出电压降低到低于标称值 100mV的电压时,通常被认为达到了这个压差。
负载电流和结点温度会影响这个压差。
最大压差值应在整个工作温度范围和负载电流条件下加以规定。
1.3效率在忽略LDO静态电流的情况下,可以采用VOUT/VIN 式子来计算效率。
1.4功耗可以根据公式PD = (VIN - VOUT) * IOUT 计算。
这里PD 与器件封装类型、环境温度(TA)和器件最大结温(TJMAX)密切相关。
如果功率耗散较高,同时又苛求较高的效率,那么应优先考虑选择降压型DC/DC 稳压器。
1.5反向泄漏保护在某些LDO的输出端上的电压高于输入端的电压的特殊应用中,反向泄漏保护可以有效防止电流从LDO的输出端流向输入端。
如果忽视这点,这种反向泄漏会损坏输入电源,特别是当输入电源为电池的时候,尤其需要重视。
1.6接地(静态)电流静态电流Iq就是输入电流Iin和负载电流IOUT之间的差值,在规定的负载电流条件下测量。
对于固定电压稳压器,Iq等于接地电流Ig。
对于可调稳压器,静态电流等于接地电流减去来自外部分压电阻网络中的电流。
1.7关断电流关断电流指设备禁用时LDO消耗的输入电流,对便携LDO来说通常低于1.0 µA。
这个指标对于便携设备关机时长待机期间的电池寿命来说很重要。
1.8输出电压精度ADI公司的LDO具有很高的输出电压精度,在工厂制造时就被精确调整到±1%之内(25℃)。
零漂移单向分流监控器AD8219Rev. AInformation furnished by Analog Devices is believed to be accurate and reliable. However, noresponsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Speci cations subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. T rademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.461.3113 ©2011 Analog Devices, Inc. All rights reserved.FUNCTIONAL BLOCK DIAGRAM9415-1Figure 1.特性高共模电压范围工作范围:4 V至80 V耐压范围:-0.3 V至+85 V缓冲输出电压增益 = 60 V/V宽工作温度范围:−40°C至+125°C出色的交流和直流性能失调漂移:±100 nV/°C(典型值)失调:±50 μV(典型值)增益漂移:±5 ppm/°C(典型值)直流共模抑制比(CMRR):110 dB(典型值)应用高端电流检测48 V电信设备电源管理基站单向电机控制精密高压电流源概述AD8219是一款高压、高分辨率分流放大器。
Mcf52259可以高达80mhz系统时钟,2个外部中断定时器(PIT)4个通用定时器(GPT),4个DMA定时器GPIO寄存器:端口输出数据寄存器(PORTn),复位时PORTn所有字节置一,R/W,读寄存器时,返回当前寄存器的值,不是引脚的值。
1,高电平,0,低电平。
可以被设置PORTn,或被统一设置SETn;被清零PORTn,或CLRn统一清零。
数据分配寄存器(DDRn),复位时,清零,R/W,置一,输出,清零输入引脚编辑/设置寄存器(PORTnP/SETn),反映当前的引脚状态,设置外部引脚当引脚为数字I/O,R/W,复位时,为当前引脚状态,读寄存器返回时当前引脚的状态,写1设置PORTn 寄存器,写0无效。
清除外部数据寄存器(CLRn),写0可以清除整个端口PORTn,也可读;写1无效,不能读,引脚分配寄存器(PnPAR),dual-function:0,GPIO,1,Primary Function;quad-function(含有CLKOUT寄存器):00 GPIO function,01 primary function,10 alternate 1 function,11 alternate 2 function,CLKOUT寄存器:00 Reserved,01 SYSCLK,10 Reserved,11 SYSCLK/2,PNQPAR:复位时,由primary function代替GPIO端口pad控制寄存器(PSRR,PDSR,PSRRL,PDSRL,PDSRH,PTHPAR):转换速率寄存器(PSRR,PSRRH,PSRRL),1,掩延时大概10个周期,0,fast;引脚驱动强度寄存器(PDSR,PDSRH,PDSRL)1,10mA,0,20mA通用定时器(GPT)GPT包含有7层可编译的预分频器驱动的16位计数器。
定时器溢出允许软件扩展超出16位计数器范围的定时器功能。
软件产品性能测试报告中国石油办公自动化系统压力测试报告中国软件评测中心2005年8月3日历史记录目录1.测试内容 (1)2.测试方法 (1)3.测试目标 (1)4.测试场景 (1)5.测试环境 (2)6.测试结果描述 (2)6.1 2M带宽登录 (2)6.2 4M带宽登录 (3)6.3 2M带宽打开word文档 (4)6.4 4M带宽打开word文档 (6)6.5 10M带宽打开word文档 (7)6.6 服务器处理能力(以登录页面为例) (8)1.测试内容本次测试是针对中国石油办公自动化系统进行的压力测试,测试的内容涵盖了两项主要的业务操作,“登录到办公系统”和“打开办公文档”2.测试方法本次采用MI公司的专业测试工具LoadRunner,采用录制\回放的方法,即首先录制IE浏览器和word发送、接收的HTML数据包,然后采用多线程的方式模拟大量客户端向服务器方发送业务请求,达到压力测试的目的.3.测试目标a)2M、4M、10M带宽的站点支持的同时在线的用户数b)服务器(IIS++SQLSERVER)的吞吐量,即每秒内可以处理的交易个数。
指标包括2个,cpu=80%的吞吐量和cpu=100%的吞吐量注:1、一般情况下,比较好的用户体验是在5秒以内完成交易,所以以上提到的同时在线用户数是指在5秒的收到响应的用户。
2、交易是指“登录到办公系统”和“打开办公文档”等业务动作。
3、本次测试的交易响应时间只包括下载页面或者word文档到本地的时间,不包括本地IE或者word展现数据的时间。
4.测试场景5.测试环境服务器是一台dell pc server (4个2.7gGcpu,4G内存),安装的软件包括IIS ,,SQLSERVER使用2个笔记本模拟客户端发出请求。
6.测试结果描述6.1 2M带宽登录从图中数据可以分析出以下结论:2M带宽下,每秒处理完成的登录个数固定在12左右,登录响应时间随虚拟用户数增加而增长。
测试简介∙目的概念∙质量定义∙产品质量∙质量维度∙测试的生命周期∙测试的主要评测方法∙测试策略∙测试类型∙测试阶段∙性能测试∙结构测试∙验收测试∙测试自动化和工具∙测试工件集目的测试的目的在于:∙核实对象之间的交互。
∙核实软件的所有构件是否正确集成。
∙核实所有需求是否已经正确实施。
∙确定缺陷并确保在部署软件之前将缺陷解决。
在很多组织中,软件测试占软件开发费用的30% 到50%。
但大多数人仍然认为软件在交付之前没有进行充分的测试。
这一矛盾根植于两个明显的事实。
第一个,测试软件十分困难。
给定程序具有无数的不同行为方式。
第二个,测试通常是在没有明确的方法,不采用必须的自动化手段和工具支持的情况下进行的。
由于软件的复杂性,无法实现完全测试,但采用周密的方法和最新技术水平的工具可以明显提高软件测试的生产率和有效性。
对于失败将导致人员伤亡这类“安全至上”的系统(如空中交通管制系统、导弹制导系统、或医用输送系统)来说,高质量的软件是系统成功的要素。
对于典型的MIS 系统,上述情况不是非常明显,但是消除缺陷造成的影响将需要相当昂贵的开支。
在软件生命周期的早期启动的执行良好的测试,将明显降低完成和维护软件的开支。
它还可以大大降低与部署质量低劣的软件相关的责任或风险,如用户的生产率低下、数据输入和计算错误,以及令人无法接受的功能行为。
现在,许多MIS 系统是“任务至上”的,也就是说当出现失败时,公司将无法正常运转并导致大量损失。
例如:银行或运输公司。
测试任务至上的系统时,必须使用安全至上的系统所采用的类似严格方法。
质量的定义质量的定义(取自The American Heritage Dictionary of the English Language, 3rd Edition, Houghton Mifflin Co., c 1992, 1996)为:Quality (kwol'i-te) n., pl.-ties. Abbr. qlty. 1.a.An inherent or distinguishingcharacteristic; a property. b.A personal trait, especially a character trait.2.Essential character; nature.3.a.Superiority of kind. b.Degree or grade ofexcellence.如定义所述,质量不是单方面的概念,而是多方面的概念。
ProductFolderSample &BuyTechnicalDocumentsTools &SoftwareSupport &CommunityTAS2555ZHCSE33A–AUGUST2015–REVISED AUGUST2015 TAS2555具有H类升压和扬声器感应功能的5.7W D类单声道音频放大器1特性•超低噪声、单声道升压D类放大器–在4Ω负载和4.2V电源电压条件下,THD+N为1%时的功率为5.7W,THD+N为10%时的功率为6.9W–在8Ω负载和4.2V电源电压条件下,THD+N为1%时的功率为3.8W,THD+N为10%时的功率为4.5W•数模转换器(DAC)+D类放大器的输出噪声(ICN)为15.9µV•1%THD+N/8Ω条件下的DAC+D类放大器的信噪比(SNR)为111dB•1W/8Ω条件下的THD+N为–90dB(具有平坦频率响应)•当频率为217Hz时,200mV pp纹波电压的电源抑制比(PSRR)为110dB•输入采样速率范围为8kHz至96kHz•内置扬声器感测–测量扬声器电流和电压–测量VBAT电压和芯片温度•通过专用实时数字信号处理器(DSP)提供扬声器保护–热量和偏移保护–检测漏音和损坏的扬声器•具有多级跟踪功能的高效H类升压转换器–500mW、8Ω、3.6V V BAT时的效率为86%–700mW、8Ω、4.2V V BAT时的效率为87%•内置自动增益控制(AGC)–限制电池流耗•可调D类开关边缘速率控制•电源–升压输入:2.9V至5.5V–模拟/数字:1.65V至1.95V–数字I/O:1.62V至3.6V•热保护、短路保护和欠压保护•I2S,左侧对齐,右侧对齐,DSP,时分复用(TDM)输入和输出接口,•用于寄存器控制的I2C或串行外设接口(SPI)• 3.47mm x3.23mm,0.5mm间距,42焊球晶圆级芯片封装(WCSP)•可使用两个TAS2555器件实现立体声配置2应用范围•移动电话•平板电脑•便携式音频底座•蓝牙扬声器3说明TAS2555是一款先进的D类音频放大器,也是一套功能完备的片上系统(SoC)。
LDO的种类
LDO是新一代的集成电路稳压器,它与三端稳压器最大的不同点在于,LDO是一个自耗很低的微型片上系统(SoC)。
LDO按其静态耗流来分,分为OmniPowerTM / MicroPowerTM / NanoPowerTM 三种产品。
OmniPowerTM LDO的静态电流在100mA-1mA,是一种静态电流稍大但性能优于三端稳压器的新型线性稳压器,适用于使用AC/DC固定电源的所有电子、电器产品。
因其需求量大,生产量大,而生产成本极低,价格十分便宜。
MicroPowerTM LDO的静态电流在10mA-100mA,是一种微功耗的低压差线性稳压器,它具有极低的自有噪音和较高的电源纹波抑制(PSRR),具有快捷的使能控制功能,给它一个高或低的电平可使它进入工作状态或睡眠状态,具有最好的性能/功率比,适用于在需要低噪音的手机电源中使用。
NanoPowerTM LDO的静态电流小于10mA,通常只有1mA。
是一种毫微功耗的低压差线性稳压器,具有极低的静态电流,稳压十分精确,最适用于需要节电的手提电子、电器产品。
见图1。
LDO的结构
LDO的结构是一个微型的片上系统,它由作电流主通道的、具有极低在线导通电阻RDS(ON)的MOSFET、肖特基二极管、取样电阻、分压电阻、过流保护、过温保护、精密基准源、差分放大器、延迟器、POK MOSFET 等专用晶体管电路在一个芯片上集成而成。
如图2。
POK(Power OK)是新一代LDO都具备的输出状态自检、延迟安全供电功能,也有称之为Power good即“电源好”。
X X X X测试报告软件名称:XXXXXX软件系统版本号:V1.0委托单位:XXXXX测试结果:测试时间:年月日批准人:检验员:测试员:目录1.项目概述............................................................... - 1 -2.测试样品............................................................... - 1 -3.测试依据............................................................... - 1 -3.1标准............................................................. - 1 -3.2文档............................................................. - 1 -4.测试目标............................................................... - 1 -5.测试环境............................................................... - 2 -5.1硬件环境......................................................... - 2 -5.2软件工具......................................................... - 2 -6.测试方法............................................................... - 2 -6.1性能测试策略..................................................... - 2 -6.2结果分析方法..................................................... - 3 -7.测试流程............................................................... - 3 -7.1测试准备......................................................... - 3 -7.2测试设计......................................................... - 4 -7.3测试实施......................................................... - 4 -7.4测试分析......................................................... - 4 -7.5测试交付......................................................... - 5 -8.测试开始条件........................................................... - 5 -9.测试结束条件........................................................... - 5 -10.测试结果.............................................................. - 6 -10.1xxx模块......................................................... - 6 -10.2xxx模块......................................................... - 7 -10.3 xxx模块........................................................ - 8 -10.4数据库存储...................................................... - 9 -10.5用户文档....................................................... - 10 -10.7测试总结....................................................... - 10 -1.项目概述本次软件测试旨在测试配电网故障分析软件系统在既有的环境下是否满足性能需求,发现软件性能瓶颈,为业主掌握系统当前性能水平提供第一手数据。
OP AMP设计详细文档 (4)1.引言: (4)2.电路功能描述: (5)2.1 运放的设计指标要求 (5)2.2 要求输出的仿真结果 (6)3.电路整体结构 (6)3.1 电路整体结构的选取 (7)3.1.1 输入差分跨导级结构的选择 (7)3.1.2 输出级结构的选择 (7)3.1.3 补偿电路 (7)3.1.4 偏置电路 (8)3.2 电路符号图(Symbol) (8)4.电路工作原理和子电路详细设计 (9)4.1电路工作原理 (9)4.1.1 单端输出的Folded cascode结构的输入级 (9)4.1.2 共源放大结构的输出级 (9)Fig 7 电流源负载共源输出级 (10)4.1.3 电路的频率特性和补偿方案 (10)4.1.3.1 负反馈电路稳定的条件 (10)4.1.3.2 相位裕度和开环频率特性 (10)4.1.3.3运放的零极点分布和Miller阻容补偿方法 (10)4.1.4偏置电路 (11)4.1.4.1电流偏置 (11)4.1.4.2电压偏置 (11)4.2子电路详细设计 (12)5.电路仿真 (15)5.1电路仿真方案 (15)5.1.1直流参数仿真 (15)5.1.1.1输入失调电压(V os)及其温度特性的仿真 (15)5.1.1.2共模电压输入范围(input commom-mode range)的仿真 (16)5.1.1.3输出动态范围(output swing)的仿真 (16)5.1.2交流参数仿真 (17)5.1.2.1开环增益(open loop gain)、增益带宽积(GBW)、相位裕度( phase margin)、增益裕度(gain margin)的仿真 (17)5.1.2.2闭环频率特性仿真 (18)5.1.2.3共模抑制比(CMRR)的仿真 (19)5.1.2.4电源电压抑制比(PSRR)的仿真 (19)5.1.2.5输出阻抗分析 (20)5.1.3瞬态参数仿真 (21)5.1.3.1转换速率(slew rate)、建立时间(setup time)的仿真 (21)5.1.3.2总谐波失真(THD)分析 (22)5.2仿真结果 (23)5.2.1参数测试结果列表 (23)5.2.2部分仿真曲线图 (24)6.开发环境(工具及其版本、厂家、库等) (27)7.参考资料 (28)表目录:表一:缩略语清单表二:运放设计指标要求表表三:运放设计仿真结果表表四:不同闭环增益下的测试结果表五:原理图中所有管子的宽长比图目录:Fig 1 Opamp整体结构Fig 2 电路采用的cascode结构Fig 3 电流源负载的共源级Fig 4 偏置电路整体图Fig 5 电路单元符号图Fig 6 Opamp的整体原理图Fig 7 电流源负载共源输出级Fig 8 负反馈系统框图Fig 9 自电压偏置电路Fig 10 输入失调电压仿真原理图Fig 11 共模电压输入范围仿真原理图 Fig 12 输出动态范围仿真原理图Fig 13 开环参数仿真原理图Fig 14 闭环特性仿真原理图Fig 15 共模抑制比仿真原理图Fig16 电源电压抑制比仿真原理图Fig 17 输出阻抗仿真原理图Fig 18 转换速率与建立时间仿真原理图Fig 19 总谐波失真仿真原理图Fig 20 系统输入失调电压VS温度特性曲线Fig 21 平均温度系数的计算Fig 22 闭环带宽幅频曲线图Fig 23 运放开环的幅频、相频曲线Fig 24 输出阻抗随频率变化的曲线图Fig 25 共模抑制比的幅频曲线图OP AMP 设计详细文档1. 引言:运算放大器(简称运放)是许多模拟系统和混合系统中的一个非常重要的组成部分,已经成为模拟电路设计中的一种最通用和最重要的集成块。
什么是PSRR什么是 PSRRPSRR,就是Power Supply Rejection Ratio 的缩写,中文含意为“电源抑制比”。
也就是说, PSRR 表示把输入与电源视为两个独立的信号源时,所得到的两个电压增益的比值。
基本计算公式为:PSRR 的单位为分贝(dB),采用对数比值,此处V1是输入电压的改变,而V2是输出电压的改变。
从上面的式子可以看出,影响输出信号的因素除了电路本身之外,还受到了供电电源的影响。
PSRR 是一个用来描述输出信号受电源影响的量,PSRR 越大,输出信号受到电源的影响越小。
这个等式的计算结果一般是零。
如果看到有电源供应商标明PSRR是正值,不要惊讶,这只是因为他们使用的是V2与V1而不是V1与V2的比值。
只要取PSRR的绝对值,就能避免一切迷惑了。
设计者们都希望PSRR的绝对值越高越好,因为PSRR绝对值越高就意味着输出上的噪音/波纹越低。
比如,80 dB 的PSRR绝对值(输出纹波比输入波纹小1万倍)就比20dB 的绝对值(输出波纹比输入波纹小10倍)要好。
还可得出,输出电压 Vout 是 Vin 与电源电压 VCC 的函数。
如果输入信号 Vin 变化了⊿Vin,输出信号的变化量⊿Vout 是由输入到输出的电压增益Av 乘以输入电压的变化量⊿Vin。
如果把电源电压变化⊿VCC 看作一个很小信号,由于电源电压变化导致的输出电压的变化量⊿Vout 则为电源电压到输出的电压增益Avo 乘以电源电压变化量⊿VCC。
不稳定的供电电压势必会影响输出信号的波形,影响的幅度取决于 PSRR。
所以需要侧重于运放等的去耦设计和电源的设计(通常较多用 LDO 线性电源给运放供电)。
PSRR 是在单位闭环增益情况下得到的,因此在负反馈应用中引起的输出变化需乘以闭环增益。
一般地,PSRR 有3个具体参数:+PSRR,-PSRR,+/-PSRR。
表示从某个电源端或两个电源端分别或同时异向低频变化,在运放差分输入端引入的传输或影响量值。