1 General description

The 74ALVT16821 high-performance BiCMOS device combines low static and dynamic

power dissipation with high speed and high output drive. It is designed for VCC operation

at 2.5 V or 3.3 V with I/O compatibility to 5 V.

The 74ALVT16821 has two 10-bit, edge triggered registers, with each register coupled to

a 3-state output buffer. The two sections of each register are controlled independently by

the clock (nCP) and output enable (nOE) control gates.

Each register is fully edge triggered. The state of each D input, one set-up time before

the LOW-to-HIGH clock transition, is transferred to the corresponding flip-flops Q output.

The 3-state output buffers are designed to drive heavily loaded 3-state buses,

MOS memories, or MOS microprocessors.

The active low output enable (nOE) controls all ten 3-state buffers independent of the

register operation. When nOE is LOW, the data in the register appears at the outputs.

When nOE is HIGH, the outputs are in high-impedance OFF-state, which means they will

neither drive nor load the bus.

2 Features and benefits

• 20-bit positive-edge triggered register

• 5 V I/O compatible

• Multiple VCC and GND pins minimize switching noise

• Bus hold data inputs eliminate the need for external pull-up resistors to hold unused

inputs

• Live insertion and extraction permitted

• Power-up reset

• Power-up 3-state

• Output capability: +64 mA and -32 mA

• Latch-up protection:

– JESD78: exceeds 500 mA

• ESD protection:

– MIL STD 883, method 3015: exceeds 2000 V

– MM: exceeds 200 V