Nxp 74hc series logic devices nxp 74hc573d 652 the 74hct573d has octal d type transparent latches featuring separate d type inputs for each latch and 3 state true outputs for bus oriented applications a latch enable le input and an output enable oe input are common to all latcheswhen le is high data at the dn inputs enter the latches in this condition the latches are transparent ie a latch output will change state each time its corresponding d input changeswhen le is low the latch