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.