Features

• Ioff supports partial-power-down mode operation

• Edge-rate control circuitry for significantly improved

noise characteristics

• Typical output skew < 250 ps

• ESD > 2000V

• TSSOP (19.6-mil pitch) and SSOP (25-mil pitch)

packages

• Industrial temperature range of −40°C to +85°C

• VCC = 5V ± 10%

CY74FCT16652T Features:

• 64 mA sink current, 32 mA source current

• Typical VOLP (ground bounce) <1.0V at VCC = 5V,

TA = 25°C

CY74FCT162652T Features:

• Balanced 24 mA output drivers

• Reduced system switching noise

• Typical VOLP (ground bounce) <0.6V at VCC = 5V,

TA= 25°C

Functional Description

These 16-bit, high-speed, low-power, registered transceivers

that are organized as two independent 8-bit bus transceivers

with three-state D-type registers and control circuitry arranged

for multiplexed transmission of data directly from the input bus

or from the internal storage registers. OEAB and OEBA control

pins are provided to control the transceiver functions. SAB and

SBA control pins are provided to select either real-time or

stored data transfer.

Data on the A or B data bus, or both, can be stored in the

internal D flip-flops by LOW-to-HIGH transitions at the

appropriate clock pins (CLKAB or CLKBA), regardless of the

select or enable control pins. When SAB and SBA are in the

real-time transfer mode, it is also possible to store data without

using the internal D-type flip-flops by simultaneously enabling

OEAB and OEBA. In this configuration, each output reinforces

its input. Thus, when all other data sources to the two sets of

bus lines are at high impedance, each set of bus lines will

remain at its last state.

This device is fully specified for partial-power-down

applications using Ioff. The Ioff circuitry disables the outputs,

preventing damaging current backflow through the device

when it is powered down.

The CY74FCT16652T is ideally suited for driving

high-capacitance loads and low-impedance backplanes.

The CY74FCT162652T has 24-mA balanced output drivers

with current-limiting resistors in the outputs. This reduces the

need for external terminating resistors and provides for

minimal undershoot and reduced ground bounce. The

CY74FCT162652T is ideal for driving transmission lines.