8位双向二进制计数器与3态输出 8-Bit Bidirectional Binary Counter with 3-STATE Outputs
General Description
The 74F579 is a fully synchronous 8-stage up/down counter with multiplexed 3-STATE I/O ports for bus-oriented applications. It features a preset capability for programmable operation, carry lookahead for easy cascading and a U/D input to control the direction of counting. All state changes, whether in counting or parallel loading, are initiated by the rising edge of the clock.
Features
■ Multiplexed 3-STATE I/O ports
■ Built-in lookahead carry capability
■ Count frequency 100 MHz typical
■ Supply current 75 mA typical
■ Guaranteed 4000V minimum ESD protection