Key facts
- Brand
- Fairchild
- Model
- MM74HC
- Industry
- Industrial
- Documents
- 6
- Languages
- EN
- Last added
- 2012-08-01
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Fairchild MM74HC High-Speed CMOS Logic Interfacing Application Note
This document provides guidance on interfacing MM74HC high-speed CMOS logic with other logic families and control circuitry. It covers interfacing at the same supply voltage, such as connecting to 74LS TTL, CD4000 CMOS, and ECL logic, as well as interfacing to circuitry operating on different voltages which may require level translation.
Read onlineFairchild MM74HC specifications
| Operating Speed Comparison | Similar to LS-TTL, half as fast as ALS-TTL |
|---|---|
| Process Technology | 3.5 micron silicon gate-recessed oxide CMOS |
| Supply Current (HC-CMOS) | 0.0025 pW |
| Supply Current (LS-TTL) | 5.0 mW |
| Supply Current (ALS-TTL) | 20mW |
| Supply Current (S-TTL) | 75 mW |
Source: FAIRCHILD Comparison of MM74HC to 74LS 74S 74ALS Logic handbook
All Fairchild MM74HC documents by type
How to use the product for one specific task, with worked examples.
- Fairchild MM74HC High-Speed CMOS Logic Interfacing Application Note 12 p
- FAIRCHILD Comparison of MM74HC to 74LS 74S 74ALS Logic handbook 8 p
- Fairchild MM74HC High-Speed CMOS AC Characteristics Application Note 8 p
- Fairchild MM54HC/MM74HC Power Dissipation Analysis 6 p
- FAIRCHILD AN-310 handbook 9 p
- Fairchild MM74HC High-Speed CMOS Logic Application Note – DC Electrical Characteristics 8 p
Questions answered in these manuals
What is the operating supply voltage range for MM74HC logic?
The high-speed CMOS family can operate from a 2 to 6V supply.
From: Fairchild MM74HC High-Speed CMOS Logic Interfacing Application Note
What is the maximum number of LSTTL equivalent loads a standard MM74HC output can drive?
A standard MM74HC output has a fanout capability of driving 10 LSTTL equivalent load.
From: Fairchild MM74HC High-Speed CMOS Logic Interfacing Application Note
How does the speed of MM54HC/MM74HC compare to other logic families?
The MM54HC/MM74HC family provides speeds similar to low power Schottky (54LS/74LS) technology, but is approximately half as fast as 54ALS/74ALS and 545/745 logic.
From: FAIRCHILD Comparison of MM74HC to 74LS 74S 74ALS Logic handbook
What is the main advantage of the MM54HC/MM74HC family?
It provides a combination of speed and power characteristics not duplicated by bipolar logic families or other CMOS families, with speeds similar to LS-TTL.
From: FAIRCHILD Comparison of MM74HC to 74LS 74S 74ALS Logic handbook
What is the standard input signal rise and fall time used for AC specifications?
The specified input signals have a rise and fall time of 6 ns.
From: Fairchild MM74HC High-Speed CMOS AC Characteristics Application Note
How much does propagation delay increase when lowering the power supply from 5V to 2V?
Propagation delays increase by about two to three times as the voltage drops from 5V to 2V.
From: Fairchild MM74HC High-Speed CMOS AC Characteristics Application Note