STMicroelectronics M74HC165B1R 8-bit Parallel-In/Serial-Out Shift Register

The M74HC165B1R is a high-speed CMOS 8-bit parallel-in/serial-out shift register designed and produced by STMicroelectronics. This integrated circuit is part of the HC family, which means it combines silicon-gate CMOS technology with the high-speed performance of HMOS to achieve the perfect balance between power consumption and speed.

This shift register features a fully synchronous serial or parallel data transfer capability. It is designed to interface directly with high-speed system buses and is compatible with most microprocessors. The device has two modes of operation: parallel (broadside) load and serial shift. In the parallel load mode, data is loaded into the associated flip-flops and appear at the outputs after the positive transition of the clock input signal. During the serial shift mode, data is shifted towards the serial output QH’ on each rising edge of the clock input signal.

The M74HC165B1R operates over a wide voltage range from 2V to 6V and offers low power consumption with a typical quiescent current of 80μA. This makes it suitable for battery-operated and low-power applications. The device also features a high noise immunity characteristic of CMOS devices and provides a typical hysteresis of 1V at the clock input to prevent false clocking from noise.

Additional features include an asynchronous master reset input (MR) that clears the register, setting all outputs LOW independent of the clock. The direct overriding load (data input enable) structure makes it possible to input data while output enable (OE) is active, which is useful for multiplexing applications.

The M74HC165B1R comes in a 16-pin plastic DIP package, making it easy to integrate into a wide variety of digital systems. With its robust design and reliable performance, the M74HC165B1R is an excellent choice for applications in data acquisition, control systems, and any digital system requiring a compact, high-performance shift register.

For detailed specifications and application information, designers and engineers are encouraged to refer to the official datasheet provided by STMicroelectronics.