SN74HC595PWR

• 8-Bit Serial-in, Serial and Parallel-Out Shift Register
• Unidirectional Shift with a Separate Output Storage Register
• 2V to 6V Supply Operation at 5V Nominal
• Up to 42 Megahertz Clock frequency, 34 Ns Propagation Delay
• 8 uA Quiescent Current
• 16-Pin TSSOP package, Gold Contact plating, -40C to 85C Range

The Texas Instruments SN74HC595PWR is an 8-bit serial-in, serial and parallel-out shift register with an output storage register, supplied in a 16-pin TSSOP. A shift register of this type converts a serial data stream clocked in on a few pins into eight parallel outputs, which is how a microcontroller drives many loads from a handful of GPIO. It operates from a 2V to 6V supply at 5V nominal, runs at up to 42 MHz with a 34 ns propagation delay and 8 uA quiescent current, and is specified from -40C to 85C. Note the record lists 4 circuits, 9 outputs and 10 output lines for a single 8-bit device; the output count should be read as eight parallel outputs plus one serial cascade output.

The '595 is the standard output expander in both production and prototype electronics: driving LED banks, seven-segment and matrix displays, relay and solenoid banks, stepper and motor driver inputs, and front-panel indicator arrays from three microcontroller pins. Multiple devices cascade through the serial output, so 8, 16, 24 or more outputs cost no additional host pins - only clock cycles. The separate storage register matters in practice because all outputs update simultaneously on a latch clock rather than rippling as data shifts through, which prevents visible flicker on displays and false actuation on relays. It appears in appliances, industrial panels and annunciators, test fixtures, signage, vending machines and any design where the processor ran out of I/O before the feature list ran out.