The M54/74HC690/691/692/693 are high-speed CMOS counters/registers fabricated in silicon gate C2MOS technology. They offer the high-speed performance of LSTTL combined with the low power consumption of CMOS. The internal circuit consists of three stages, including a buffer output, which provides high noise immunity and stable output. These devices integrate a synchronous counter, a four-bit D-type register, and quadruple two-line to one-line multiplexers with three-state outputs in a single 20-pin package. The counter can be programmed using the data inputs and features enable P and enable T inputs for easy expansion. The device can function as either a counter or a parallel register output.
This document is a technical datasheet for the SGS-THOMSON M54/74HC690/691/692/693 series of microelectronics components. These devices are high-speed CMOS counters and registers fabricated in silicon gate CMOS technology, offering low power consumption combined with LSTTL speed performance.
The datasheet details the internal circuitry, which includes a synchronous counter, four-bit D-type register, and quadruple two-line to one-line multiplexers with three-state outputs. It provides comprehensive information on pin connections, logic symbols, truth tables, timing charts for various modes (HC690/691 vs HC692/693), equivalent circuits, and mechanical data for the PLCC20 package.
| Max Supply Current | 4 mA |
|---|---|
| Noise Immunity Voltage | 28 % Voc |
| Operating Voltage Range | 2 V to 6 V |
The internal counter is selected when the R/C input is low, and the register is selected when it is high.
The outputs can drive 15 LSTTL loads if in a plastic package and 10 LSTTL loads if in a ceramic package.