74HC/HCT74 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A. The 74HC/HCT74 are dual positive-edge triggered, D-type flip-flops with individual data (D) inputs, clock (CP) inputs, set (SD) and reset (RD) inputs; also complementary Q and Q outputs. The set and reset are asynchronous active LOW inputs and operate independently of the clock input. Information on the data input is transferred to the Q output on the LOW-to-HIGH transition of the clock pulse. The D inputs must be stable one set-up time prior to the LOW-to-HIGH clock transition for predictable operation. Schmitt-trigger action in the clock input makes the circuit highly tolerant to slower clock rise and fall times.
The Philips 74HC/HCT74 is a high‑speed Si‑gate CMOS dual D‑type flip‑flop with asynchronous set and reset inputs. It is pin‑compatible with low‑power Schottky TTL and complies with JEDEC standard 7A. The document provides electrical characteristics, timing parameters, package options and recommended soldering methods.
Key sections include features, quick reference data, ordering information, pin description, functional tables, DC/AC characteristics, package outlines and detailed soldering recommendations for DIP, SO, SSOP and TSSOP packages.
| Maximum clock frequency (fmax) | 76 MHz (HC) / 59 MHz (HCT) |
|---|---|
| Propagation delay (nCP to nQ) | 15 ns (HC) / 18 ns (HCT) |
| Input capacitance | 3.5 pF |
| Maximum soldering temperature | 260 °C |
The HC version can operate up to 76 MHz, while the HCT version is limited to 59 MHz.
The soldering temperature should not exceed 260 °C, and contact time must be limited to a few seconds.
The input capacitance is specified as 3.5 pF.