These dual 4-bit D-type edge-triggered flip-flops feature 3-state
outputs designed specifically as bus drivers. They are particularly
suitable for implementing buffer registers, I/O ports, bidirectional
bus drivers, and working registers.
The edge-triggered flip-flops enter data on the low-to-high
transition of the clock (CLK) input. The SN54ALS874B, SN74ALS874B,
and SN74AS874 have clear ()
inputs and noninverting Q outputs. The SN74ALS876A and SN74AS876 have
preset () inputs and
inverting Q\ outputs; taking low
causes the four Q or Q\ outputs to go low independently of the clock.
The SN54ALS874B is characterized for operation over the full
military temperature range of -55°C to 125°C. The
SN74ALS874B, SN74ALS876A, SN74AS874, and SN74AS876 devices are
characterized for operation from 0°C to 70°C.