Content for 74HC74

74HC74

The 74HC74 and 74HCT74 are dual positive edge triggered D-type flip-flop. They have individual data (nD), clock (nCP), set (nSD) and reset (nRD) inputs, and complementary nQ and nQ outputs. Data at the nD-input, that meets the set-up and hold time requirements on the LOW-to-HIGH clock transition, is stored in the flip-flop and appears at the nQ output. Schmitt-trigger action in the clock input, makes the circuit highly tolerant to slower clock rise and fall times. Inputs include clamp diodes that enable the use of current limiting resistors to interface inputs to voltages in excess of VCC.

Nostalgic CMOS Frequency Meter

“The CMOS series of integrated circuits appeared shortly after the TTL series. This means that at the beginning of the 70s it was available on the market in an accessible way for any user. Hence the nostalgia of those who …

Home Assistant Deep BLE Relay-Low energy

“BLE relay device for Home Assistant that, for the most of time is in a very low energy state and only a few seconds per minute is awake. The purpose of this project, was to develope a BLE relay device …

Homemade Successive Approximation Register ADC

“This is a homemade 7-bit SAR ADC using discrete components for principle study. The following is an introduction to a Successive Approximation Register Analog to Digital Converter (SAR ADC) that I made myself for principle study, and observing the conversion …

Pineapple ONE

“32 bit RISC-V homemade In this article I will describe how I designed and made a functional 32 bit RISC-V CPU at home. Specifications: “Max” clock speed: 500 kHz Program memory: 512 kB RAM size: 512 kB VGA …

Frequency Counter With Variable Gate Time

“Frequency counter (reciprocal) Gate time selectable from 0.1 second up to 60 seconds Frequency range from 0.1 Hz up to 10 MHz (tested) Input 3.3V and 5V safe Uses a STM32F103C8 (Blue Pill) and 16x4 LCD Supplies …

7400 Series Logic Clock

“This project is 7400 series logic ICs based clock. It keeps time solely based on discrete logic ICs and a stable clock source. For the display LEDs, I am using common anode 7 segment displays. This variant is 0.56 …

The World’s Least Powerful Computer? 1-bit Cpu With The Mc14500b Industrial Control Unit

“I came across this weird chip a few months ago. Designed by Motorola in the 70s, its purpose is to replace the “ladder logic” relays in industrial process control so all it needs to do is make simple decisions based …

A digital quartz clock from scratch

“After 20+ years of programming, I wanted to get some understanding of the electronics that make my career possible. I had built the basic individual logic gates with transistors on a breadboard, but to build anything meaningful I needed loads …

Project  Battledip

Battledip

“This project is a good introduction to digital logic circuits as it will utilize basic concepts of Boolean logic and memory in circuits. You will be using chips such as a Dual D-Type Flip Flop, Quad 2-input XNOR gate, and …

VXO based PLL Frequency Synthesizer for 7 MHz

“In EMRFD, 4.10, Wes provides the schema for a versatile VXO - extending frequency synthesizer. Although, I referred him to Wes for help, a reader asked me some questions and I ended up designing some pieces for him. In order …

Frequency synthesizer for my Jupiter receiver

“Radio astronomy offers much fun + learning for the radio homebuilder — example topics include how to design and make antennas, LNAs, receivers, and frequency synthesizers from HF to microwave. Further we may craft op-amp analog integrators to remove background noise, and …