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PS2104A 02/07/97

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PI74LCX646

PI74LCX652

Fast CMOS 3.3V 8-Bit Registered Transceiver

Product Features

• Functionally compatible with FCT3, LVT, and

74 series 646 and 652 families of products

• Tri-State outputs

• 5V Tolerant inputs and outputs

• Balanced sink and source output drives (24 mA)

• Low ground bounce outputs

• Supports live insertion

• ESD Protection exceeds 2000V, Human Body Model

200V, Machine Model

• Packages available:

– 24-pin 209-mil wide plastic SSOP (H)

– 24-pin 173-mil wide plastic TSSOP (L)

– 24-pin 150-mil wide plastic QSOP (Q)

– 24-pin 300-mil wide plastic SOIC (S)

Logic Block Diagram

Product Description

Pericom Semiconductor’s PI74LCX series of logic circuits are pro-

duced in the Company’s advanced 0.6 micron CMOS technology,

achieving industry leading speed grades.

The PI74LCX646 and PI74LCX652 are designed with a bus

transceiver with 3-state D-type flip-flops and control circuitry

arranged for multiplexed transmission of data directly from the data

bus or from the internal storage registers. The PI74LCX652 utilizes

GAB and GBA signals to control the transceiver functions. The

PI74LCX646 uses the enable control (G) and direction pins (DIR)

to control the transceiver functions. SAB and SBA control pins are

used to select either real-time or stored data transfer. The circuitry

used for select control will eliminate the typical decoding glitch that

occurs in a multiplexer during the transition between real-time and

stored data. A low input level selects real-time data and a high

selects stored data.

The PI74LCX646 and PI74LCX652 can be driven from either 3.3V

or 5.0V devices allowing this device to be used as a translator in a

mixed 3.3/5.0V system.

0D

CPAB

CPBA

SBA

DIR

G

SAB

0D

A REG

B REG

1 OR 8 CHANNELS

TO 7 OTHER CHANNELS

GBA

GAB

PI74LPT652 ONLY

PI74LPT646

ONLY