SN55121 Datasheet, PDF (1/7 Pages) Texas Instruments – DUAL LINE DRIVERS

D Designed for Digital Data Transmission
Over 50-Ω to 500-Ω Coaxial Cable, Strip
Line, or Twisted Pair
D High Speed
t_pd = 20 ns Maximum at C_L = 15 pF
D TTL Compatible With Single 5-V Supply
D 2.4-V Output at I_OH = – 75 mA
D Uncommitted Emitter-Follower Output
Structure for Party-Line Operation
D Short-Circuit Protection
D AND-OR Logic Configuration
D Designed for Use With Triple Line
Receivers SN55122, SN75122
D Designed to Be Interchangeable With
Signetics N8T13
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 compatible 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 uncommitted 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 1
1B 2
1C 3
1D 4
1E 5
1F 6
1Y 7
GND 8
16 V_CC
15 2F
14 2E
13 2D
12 2C
11 2B
10 2A
9 2Y
SN55121 . . . FK PACKAGE
(TOP VIEW)
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
NC – No internal connection
THE SN75121 IS NOT
RECOMMENDED FOR NEW DESIGNS
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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.
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Copyright © 1998, Texas Instruments Incorporated
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