Integrated Device Technology, Inc.

The IDT logo is a registered trademark of Integrated Device Technology, Inc.

FUNCTIONAL BLOCK DIAGRAM

FAST CMOS 16-BIT BUS

TRANSCEIVER/

REGISTERS (3-STATE)

IDT54/74FCT16646T/AT/CT/ET

IDT54/74FCT162646T/AT/CT/ET

1

1

1

OE

1

DIR

1

SBA

1

SAB

1

CLKBA

1

CLKAB

2540 drw 01

TO 7 OTHER CHANNELS

B REG

A REG

D

C

C

D

2

2

OE

2

DIR

2

SBA

2

SAB

2

2

CLKBA

2

CLKAB

2540 drw 02

TO 7 OTHER CHANNELS

B REG

A REG

D

C

C

D

74FCT162646T/AT/CT/ET 16-bit registered transceivers are

built using advanced dual metal CMOS technology. These

high-speed, low-power devices are organized as two inde-

pendent 8-bit bus transceivers with 3-state D-type registers.

The control circuitry is organized for multiplexed transmission

of data between A bus and B bus either directly or from the

internal storage registers. Each 8-bit transceiver/register fea-

tures direction control (xDIR), over-riding Output Enable con-

trol (x

OE) and Select lines (xSAB and xSBA) to select either

real-time data or stored data. Separate clock inputs are

provided for A and B port registers. Data on the A or B data

bus, or both, can be stored in the internal registers by the

LOW-to-HIGH transitions at the appropriate clock pins. Flow-

through organization of signal pins simplifies layout. All inputs

are designed with hysteresis for improved noise margin.

The IDT54/74FCT16646T/AT/CT/ET are ideally suited for

driving high-capacitance loads and low-impedance

backplanes. The output buffers are designed with power off

disable capability to allow "live insertion" of boards when used

as backplane drivers.

The IDT54/74FCT162646T/AT/CT/ET have balanced

output drive with current limiting resistors. This offers low

ground bounce, minimal undershoot, and controlled output

fall times–reducing the need for external series terminating

resistors. The IDT54/74FCT162646T/AT/CT/ET are plug-in

replacements for the IDT54/74FCT16646T/AT/CT/ET and

54/74ABT16646 for on-board bus interface applications.

MILITARY AND COMMERCIAL TEMPERATURE RANGES

AUGUST 1996

©1996 Integrated Device Technology, Inc.

5.13

DSC-4231/9

1

DESCRIPTION:

The IDT54/74FCT16646T/AT/CT/ET and IDT54/

FEATURES:

• Common features:

–

0.5 MICRON CMOS Technology

–

High-speed, low-power CMOS replacement for

ABT functions

–

–

Low input and output leakage

≤1µA (max.)

–

ESD > 2000V per MIL-STD-883, Method 3015;

> 200V using machine model (C = 200pF, R = 0)

–

Packages include 25 mil pitch SSOP, 19.6 mil pitch

TSSOP, 15.7 mil pitch TVSOP and 25 mil pitch Cerpack

–

Extended commercial range of -40

°C to +85°C

±10%

• Features for FCT16646T/AT/CT/ET:

–

–

Power off disable outputs permit “live insertion”

–

°C

• Features for FCT162646T/AT/CT/ET:

–

Balanced Output Drivers:

±24mA (commercial),

±16mA (military)

–

Reduced system switching noise

–

°C