The MC74HC137 is identical in pinout to the LS137. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LSTTL outputs. The HC137 decodes a threebit Address to oneofeight activelow outputs. The device has a transparent latch for storage of the Address. Two Chip Selects, one activelow and one activehigh, are provided to facilitate the demultiplexing, cascading, and chipselecting functions. The demultiplexing function is accomplished by using the Address inputs to select the desired device output, and then by using one of the Chip Selects as a data input while holding the other one active. The HC137 is the inverting version of the HC237. |