74LS77中文资料摩托罗拉数据手册PDF规格书

4-BIT D LATCH

The TTL/MSI SN54/74LS75 and SN54/74LS77 are latches used as temporarystorage for binary information between processing units and input/out putor indicator units. Information present at a data (D) input is transferred to the Q output when the Enable is HIGH and the Q output will follow the data inputas long as the Enable remainsHIGH.

When the Enable goes LOW, the information(that was present at the data input at the time the transition occurred)is retained at the Q output until the Enable is permitted to go HIGH. The SN54 /74LS75 features complementary Q and Qoutput from a4-bit latchand is available in the 16-pin packages. For higher component density applications the SN54/74LS77 4-bit latch is available in the 14-pin package with Qoutputs omitted.