The M54/74HC374 and M54/74HC534 are high-speed CMOS octal D-type flip-flops with 3-state outputs fabricated with silicon gate C2MOS technology. They have the same high-speed performance as LSTTL combined with true CMOS low power consumption. These 8-bit D-type flip-flops are controlled by a clock input (CK) and an output enable input (OE). On the positive transition of the clock, the Q outputs will be set to the logic state that were set up at the D inputs (HC374) or their complements (HC534). While the OE input is low, the eight outputs will be in a normal logic state (high or low logic level), and while high level, the outputs will be in a high impedance state. The output control does not affect the internal operation of the flip-flops. That is, the old data can be retained or the new data can be entered.
The M54/74HC374 (non‑inverting) and M54/74HC534 (inverting) are high‑speed CMOS octal D‑type flip‑flops with three‑state outputs. They operate from a 2 V to 6 V supply, provide up to 77 MHz typical clock frequency, and feature low‑power dissipation. All eight outputs can be disabled to a high‑impedance state via the OE pin, allowing bus‑organized systems.
Electrical specifications include a supply voltage range of 2‑6 V, typical propagation delay tPHL of 4.5 ns, power dissipation up to 500 mW, and an output drive capability of 15 LSTTL loads. Absolute maximum ratings, recommended operating conditions, DC and AC characteristics, and mechanical dimensions are detailed in the following sections.
| Typical maximum clock frequency | 77 MHz |
|---|---|
| Power dissipation (max) | 500 mW |
| Output drive capability | 15 LSTTL loads |
The flip‑flop can operate up to 77 MHz typical at a 5 V supply.
It has eight outputs, all of which can be placed in a high‑impedance three‑state condition.