1. General description
The 74AHC74; 74AHCT74 is a high-speed Si-gate CMOS device and is pin compatible with
Low-Power Schottky TTL (LSTTL). It is specified in compliance with JEDEC standard No. 7-A.
The 74AHC74; 74AHCT74 is a dual positive-edge triggered, D-type flip-flop with individual data
inputs (D), clock inputs (CP), set inputs (SD) and reset inputs (RD). It also has complementary
outputs (Q and Q).
The set and reset are asynchronous active LOW inputs that operate independent 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 data 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.
2. Features and benefits
• Balanced propagation delays
• All inputs have Schmitt-trigger actions
• Inputs accept voltages higher than VCC
• Input levels:
• For 74AHC74: CMOS level
• For 74AHCT74: TTL level
• ESD protection:
• HBM EIA/JESD22-A114E exceeds 2000 V
• MM EIA/JESD22-A115-A exceeds 200 V
• CDM EIA/JESD22-C101C exceeds 1000 V
• Multiple package options
• Specified from -40 °C to +85 °C and from -40 °C to +125 °C