There is no ‘latch pin’ on MC74HC164A shift register

latchshift-register

Unlike a 74HC595, this shift register (http://www.onsemi.com/pub_link/Collateral/MC74HC164A-D.PDF) doesn't have a latch pin. How then do I output the data stored in the registers (to something like an LED array)?

Thanks.

Best Answer

The '595 has two sets of latches; one is an input latch that receives the external data serially, and the other is an output latch that receives the data in parallel from the input latch.

The '164 has no discrete output latch; all data is output in parallel as it is received serially. The timing diagram on page 7 shows this.