SN55121 Datasheet | Texas Instruments

description The SN55121 and SN75121 dual line drivers are designed for digital data transmission over lines having impedances from 50 to 500 Ω. They are also patible with standard TTL logic and supply-voltage levels. The low-impedance emitter-follower outputs of the SN55121 and SN75121 can drive terminated lines such as coaxial cable or twisted pair. Having the outputs unmitted allows wired-OR logic to be performed in party-line applications. Output short-circuit protection is provided by an internal clamping network that turns on when the output voltage drops below approximately 1.5 V. All of the inputs are in conventional TTL configuration and the gating can be used during power-up and power-down sequences to ensure that no noise is introduced to the line. The SN55121 is characterized for operation over the full military temperature range of - 55°C to 125°C. The SN75121 is characterized for operation from 0°C to 70°C. SN55121, SN75121 DUAL LINE DRIVERS SLLS074C - SEPTEMBER 1973 - REVISED MAY 1998 SN55121 . . . J PACKAGE SN75121 . . . D OR N PACKAGE (TOP VIEW) 1A 1B 1C 1D 1E 1F 1Y GND 1 2 3 4 5 6 7 8 16 VCC 15 2F 14 2E 13 2D 12 2C 11 2B 10 2A 9 2Y SN55121 . . . FK PACKAGE (TOP VIEW) 1B 1A NC VCC 2F 1C 3 2 1 20 19 4 18 2E 1D 5 17 2D NC 6 16 NC 1E 7 15 2C 1F 8 14 2B 9 10 11 12 13 1Y GND NC 2Y 2A - No internal connection THE SN75121 IS NOT REMENDED FOR NEW DESIGNS Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. - POST OFFICE BOX 655303 DALLAS, TEXAS 75265 Copyright © 1998, Texas Instruments Incorporated 1 SN55121, SN75121 DUAL LINE...