SN75C189DR.A中文资料德州仪器数据手册PDF规格书

Meet or Exceed the Requirements of

TIA/EIA-232-F and ITU Recommendation

V.28

Low Supply Current . . . 420 mA Typ

Preset On-Chip Input Noise Filter

Built-in Input Hysteresis

Response and Threshold Control Inputs

Push-Pull Outputs

Functionally Interchangeable and

Pin-to-Pin Compatible With

Texas Instruments SN75189/SN75189A and

Motorola MC1489/MC1489A

Package Options Include Plastic

Small-Outline (D) and Shrink Small-Outline

(DB) Packages, and Standard Plastic (N)

DIP

description

The SN75C189 and SN75C189A are low-power, bipolar, quadruple line receivers that are used to interface data

terminal equipment (DTE) with data circuit-terminating equipment (DCE). These devices have been designed

to conform to TIA/EIA-232-F.

The SN75C189 has a 0.33-V typical hysteresis, compared with 0.97 V for the SN75C189A. Each receiver has

provision for adjustment of the overall input threshold levels. This is achieved by choosing external series

resistors and voltages to provide bias levels for the response-control pins. The output is in the high logic state

if the input is open circuit or shorted to ground.

These devices have an on-chip filter that rejects input pulses of less than 1-ms duration. An external capacitor

can be connected from the control pins to ground to provide further input noise filtering for each receiver.

The SN75C189 and SN75C189A have been designed using low-power techniques in a bipolar technology. In

most applications, these receivers interface to single inputs of peripheral devices such as UARTs, ACEs, or

microprocessors. By using sampling, such peripheral devices usually are insensitive to the transition times of

the input signals. If this is not the case, or for other uses, it is recommended that the SN75C189 and SN75C189A

outputs be buffered by single Schmitt input gates or single gates of the HCMOS, ALS, or 74F logic families.

The SN75C189 and SN75C189A are characterized for operation from 0°C to 70°C.