Overview
The MC74HC74A, produced by onsemi, is a high-performance silicon-gate CMOS device that consists of two D flip-flops. Each flip-flop has individual Set, Reset, and Clock inputs. The device is identical in pinout to the LS74 and is compatible with standard CMOS outputs. With the use of pullup resistors, it is also compatible with LSTTL outputs. Information at the D-input is transferred to the corresponding Q output on the next positive-going edge of the clock input. Both Q and Qbar outputs are available from each flip-flop, and the Set and Reset inputs are asynchronous.
Key Specifications
| Parameter | Value | Unit | Conditions |
|---|---|---|---|
| Operating Voltage Range | 2.0 to 6.0 | V | |
| Output Drive Capability | 10 LSTTL Loads | ||
| Maximum Clock Frequency | Up to 28 MHz at VCC = 6.0 V | MHz | 50% Duty Cycle |
| Propagation Delay, Clock to Q or Qbar | 17 to 150 ns | ns | VCC = 2.0 to 6.0 V |
| Input Current | 1.0 μA | μA | VIN = VCC or GND |
| Maximum Input Capacitance | 10 pF | pF | |
| Power Dissipation Capacitance (Per Enabled Output) | 5.0 pF (Typical at 25°C, VCC = 5.0 V) | pF |
Key Features
- Outputs directly interface to CMOS, NMOS, and TTL.
- High noise immunity characteristic of CMOS devices.
- In compliance with the requirements defined by JEDEC Standard No. 7A.
- Chip complexity: 136 FETs or 34 equivalent gates.
- Pb-free packages are available.
- AEC-Q100 qualified and PPAP capable for automotive and other applications requiring unique site and control change requirements.
Applications
The MC74HC74A is suitable for a variety of applications, including:
- Digital counters and dividers.
- Shift registers.
- Memory elements in digital systems.
- Automotive systems requiring high reliability and compliance with automotive standards.
- General-purpose digital logic circuits where high noise immunity and low power consumption are essential.
Q & A
- What is the operating voltage range of the MC74HC74A?
The operating voltage range is from 2.0 to 6.0 volts.
- How many D flip-flops are included in the MC74HC74A?
The device consists of two D flip-flops.
- What is the maximum clock frequency for the MC74HC74A?
The maximum clock frequency is up to 28 MHz at VCC = 6.0 V.
- Are the outputs of the MC74HC74A compatible with other logic families?
Yes, the outputs directly interface to CMOS, NMOS, and TTL.
- What is the input current of the MC74HC74A?
The input current is 1.0 μA.
- Is the MC74HC74A suitable for automotive applications?
Yes, it is AEC-Q100 qualified and PPAP capable for automotive and other applications requiring unique site and control change requirements.
- What is the propagation delay from the clock to Q or Qbar?
The propagation delay ranges from 17 to 150 ns depending on the VCC voltage.
- Does the MC74HC74A have Pb-free packages available?
Yes, Pb-free packages are available.
- What are the asynchronous inputs on the MC74HC74A?
The Set and Reset inputs are asynchronous.
- What is the maximum input capacitance of the MC74HC74A?
The maximum input capacitance is 10 pF.
