DS3885资料

DS1287A

Real Time ClockDS1287A

022798 1/1FEATURES

•Drop-in replacement for IBM AT computer clock/ca-lendar

•Pin compatible with the MC146818A

•Totally nonvolatile with over 10 years of operation inthe absence of power

•Self-contained subsystem includes lithium, quartz,and support circuitry

•Counts seconds, minutes, hours, day of the week,date, month, and year with leap year compensation

•Binary or BCD representation of time, calendar, andalarm

•12- or 24-hour clock with AM and PM in 12-hour mode

•Daylight Savings Time option

•Selectable between Motorola and Intel bus timing

•Multiplex bus for pin efficiency

•Interfaced with software as 64 RAM locations

–14 bytes of clock and control registers

–50 bytes of general purpose RAM

•Programmable square wave output signal

•Bus-compatible interrupt signals (IRQ)

•Three interrupts are separately software-maskableand testable

广州周立功单片机发展有限公司 Tel：（020）38730976 38730977 Fax：38730925 http：//

SP3481/SP3485 +3.3V低功耗半双工RS-485收发器

z RS-485和RS-422收发器

z 工作电压为+3.3V

z 可与+0.5V的逻辑电路共同工作

z 驱动器/接收器使能

z 低功耗关断模式（SP3481）

z -7V～+12V的共模输入电压范围

z 允许在同一串行总线上连接32个收发器

z 与工业标准75176管脚配置兼容

z 驱动器输出短路保护

描述

SP3481和SP3485是一系列+3.3V低功耗半双工收发器，它们完全满足RS-485和RS-422串行协议

的要求。这两个器件与Sipex的SP481、SP483和SP485的管脚互相兼容，同时兼容工业标准规范。SP3481

和SP3485符合RS-485和RS-422串行协议的电气规范，数据传输速率可高达10Mbps（带负载）。SP3481

还包含低功耗关断模式。

SP3481和SP3485

绝对最大额定值

下面列出的是器件正常工作的额定值，并未涉及器件在这些条件或超出这些条件下的功能操作。器件

不能长时间工作在绝对最大额定值条件下，否则会影响其可靠性。

Vcc………………………………………………………………………………………………………..+6.0V

输入电压

逻辑……………………………………………………………………………………… －0.3～+6.0V

驱动器 …………………………………………………………………………………… －0.3～+6.0V

接收器………………………………………………………………………………………………±15V

贮存温度……………………………………………………………………………………...－65℃～+150℃

封装功耗

8脚NSOIC…..…………………………………………………………………………………………..600mW

LM285Ć1.2, LM385Ć1.2, LM385BĆ1.2

MICROPOWER VOLTAGE REFERENCES

SLVS075H − APRIL 1989 − REVISED FEBRUARY 2005

1POST OFFICE BOX 655303 • DALLAS, TEXAS 75265DOperating Current Range

− LM285...10 µA to 20 mA

− LM385...15 µA to 20 mA

− LM385B...15 µA to 20 mA

D1% and 2% Initial Voltage Tolerance

DReference Impedance

− LM385...1 Ω Max at 25°C

− All Devices...1.5 Ω Max Over Full

Temperature Range

DVery Low Power Consumption

DApplications

− Portable Meter References

− Portable Test Instruments

− Battery-Operated Systems

− Current-Loop Instrumentation

− Panel Meters

DInterchangeable With Industry Standard

LM285-1.2 and LM385-1.2

description/ordering information

These micropower, two-terminal, band-gap voltage references operate over a 10-µA to 20-mA current range

and feature exceptionally low dynamic impedance and good temperature stability. On-chip trimming provides

KSZ8851-16MLL/MLLI/MLLU

Single-Port Ethernet MAC Controller

with 8-Bit or 16-Bit Non-PCI Interface Revision 2.2

March 11, 2014 1 Revision 2.2

General Description

The KSZ8851M-series is a single-port controller chip with a non-PCI CPU interface and is available in 8-bit and 16-bit bus designs. This datasheet describes the 48-pin LQFP KSZ8851-16MLL for applications requiring high-performance from single-port Ethernet Controller with 8-bit or 16-bit generic processor interface. The KSZ8851-16MLL offers the most cost-effective solution for adding high-throughput Ethernet connectivity to traditional embedded systems.

The KSZ8851-16MLL is a single chip, mixed analog/digital device offering Wake-on-LAN technology for effectively addressing Fast Ethernet applications. It consists of a fast Ethernet MAC controller, an 8-bit or 16-bit generic host processor interface and incorporates a unique dynamic memory pointer with 4-byte buffer boundary and a fully utilizable 18KB for both TX (allocated 6KB) and RX (allocated 12KB) directions in host buffer interface.