Members of the Texas Instruments

Widebus Family

Support the VME64 ETL Specification

Reduced, TTL-Compatible, Input Threshold

Range

High-Drive Outputs (IOH = –60 mA,

IOL = 90 mA) Support 25-Ω Incident-Wave

Switching

VCCBIAS Pin Minimizes Signal Distortion

During Live Insertion

Internal Pullup Resistor on OE Keeps

Outputs in High-Impedance State During

Power Up or Power Down

Distributed VCC and GND Pins Minimize

High-Speed Switching Noise

Equivalent 25-Ω Series Damping Resistor

on B Port

Bus Hold on Data Inputs Eliminates the

Need for External Pullup/Pulldown

Resistors

description

The ’ABTE16245 devices are 16-bit (dual-octal)

noninverting 3-state transceivers designed for

synchronous two-way communication between

data buses. The control-function implementation

minimizes external timing requirements. These

devices can be used as two 8-bit transceivers or

one 16-bit transceiver. They allow data transmission from the A bus to the B bus or from the B bus to the A bus,

depending on the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to

disable the device so that the buses are effectively isolated. When OE is low, the device is active.

The B port has an equivalent 25-Ω series output resistor to reduce ringing. Active bus-hold inputs also are on

the B port to hold unused or floating inputs at a valid logic level.

The A port provides for the precharging of the outputs via VCCBIAS, which establishes a voltage between 1.3 V

and 1.7 V when VCC is not connected.

Active bus-hold circuitry holds unused or undriven inputs at a valid logic state. Use of pullup or pulldown resistors

with the bus-hold circuitry is not recommended.