8-bit serial-to-parallel shift register in a compact 2.5x2.5 mm X1QFN
The SN74HC595BRWNR accepts serial data and outputs it on eight parallel tri-state lines.
The 2V to 6V supply range means this part works with 3.3V and 5V systems without a level translator. At 3.3V, the input thresholds are compatible with standard 3.3V CMOS outputs. The 74HC family provides good noise margin at both supply voltages, which matters when the shift register is on a long PCB trace or ribbon cable.
Tri-state outputs and daisy-chaining
Tri-state outputs let multiple shift registers share a common data bus. The serial output pin (QH') allows daisy-chaining an unlimited number of devices for applications like large LED matrix displays or multi-digit seven-segment readouts. The output enable pin (OE) can tri-state all outputs simultaneously, useful for power saving or bus arbitration.
The SN74HC595BRWNR comes in a 16-XFQFN Exposed Pad package, supplier device package 16-X1QFN measuring 2.5x2.5 mm. This package is a space-saver compared to the SOIC or TSSOP versions of the 74HC595, but requires a stencil and reflow profile suited to QFN assembly.