The SN54ACT74 and SN74ACT74 are dual positive-edge-triggered D-type flip-flops with clear and preset functions. When PRE and CLR are inactive (high), data meeting the setup-time requirements is transferred to the outputs on the positive-going edge of the clock pulse. Clock triggering occurs at a voltage level and is not directly related to the rise time of the clock pulse. Following the hold-time interval, data at D can be changed without affecting the levels at the outputs. The SN54ACT74 is characterized for operation over the full military temperature range of –55°C to 125°C. The SN74ACT74 is characterized for operation from –40°C to 85°C.
The SN54ACT74 and SN74ACT74 are dual positive‑edge‑triggered D‑type flip‑flops with clear (CLR) and preset (PRE) inputs. They are offered in a variety of packages, including plastic, small‑outline, thin‑shrink, ceramic chip carriers, flat‑packs and standard plastic.
The datasheet lists absolute maximum ratings, recommended operating conditions, electrical, timing and switching characteristics, and includes an important notice about warranty and critical‑application usage. Temperature ranges are –55 °C to 125 °C for the SN54ACT74 and –40 °C to 85 °C for the SN74ACT74.
| Operating temperature (SN54ACT74) | -55 °C to 125 °C |
|---|---|
| Operating temperature (SN74ACT74) | -40 °C to 85 °C |
They set or reset the outputs, regardless of the levels of the other inputs.