Datasheet
DS8921, DS8921A, DS8921AT
www.ti.com
SNLS374C –MAY 1998–REVISED APRIL 2013
DS8921/DS8921A/DS8921AT Differential Line Driver and Receiver Pair
Check for Samples: DS8921, DS8921A, DS8921AT
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FEATURES
DESCRIPTION
The DS8921, DS8921A are Differential Line Driver
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• 12 ns Typical Propagation Delay
and Receiver pairs designed specifically for
• Output Skew - 0.5 ns Typical
applications meeting the ST506, ST412 and ESDI
• Meet the Requirements of EIA Standard RS-
Disk Drive Standards. In addition, these devices meet
422
the requirements of the EIA Standard RS-422.
• Complementary Driver Outputs
The DS8921, DS8921A receivers offer an input
sensitivity of 200 mV over a ±7V common mode
• High Differential or Common-Mode Input
operating range. Hysteresis is incorporated (typically
Voltage Ranges of ±7V
70 mV) to improve noise margin for slowly changing
• ±0.2V Receiver Sensitivity over the Input
input waveforms.
Voltage Range
The DS8921, DS8921A drivers are designed to
• Receiver Input Hysteresis-70 mV Typical
provide unipolar differential drive to twisted pair or
• DS8921AT Industrial Temperature Operation:
parallel wire transmission lines. Complementary
(−40°C to +85°C)
outputs are logically ANDed and provide an output
skew of 0.5 ns (typ.) with propagation delays of
12 ns.
The DS8921, DS8921A are designed to be
compatible with TTL and CMOS.
Connection Diagram
DS8921/DS8921A/DS8921AT
See Package Number D (R-PDSO-G8) or P (R-PDIP-T8)
Truth Table
Receiver Driver
Input V
OUT
Input V
OUT
V
OUT
V
ID
≥ V
TH
(MAX) 1 1 1 0
V
ID
≤ V
TH
(MIN) 0 0 0 1
Open 1
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PRODUCTION DATA information is current as of publication date.
Copyright © 1998–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.