Referring to the following chaser circuit diagram below, we can see a low-frequency, astable oscillator circuit, made up of two gates, IC1a and IC1b, from the IC 4011 quad two-input NAND gate. The operating frequency of this astable is determined by the values of C1 and R11. This circuit configuration works well as a clock-pulse […]
Lamps and Lights
LED Chaser Circuit using IC 74LS164: LEDs illuminate in Bar Mode then Shut off together or one by one
This circuit is actually a little more advanced LED chaser scanner circuit using two 74LS164 Shift Register ICs together with one NE555 Timer, and yep the light effect looks somewhat similar to those old Knight Rider or Mustang scanner lights which move from sides toward center. The LEDs are arranged in two strips, or sometimes […]
LED Arrow Direction Indicator Circuit
The arrow-shaped LED direction indicator circuit utilizing the 74LS164 based IC and a configuration of 14 LEDs arranged in the shape of an arrow is a captivating and visually appealing project designed to create an eye-catching display. This circuit is designed to illuminate the LEDs gradually, forming the shape of an arrow, and once the […]
Darkness Activated PIR Lamp Circuit
A very simple darkness activated or night activated PIR lamp circuit project has been explained in the following article. Further in the article we also learn how to upgrade this circuit with an additional emergency lamp facility. This darkness activated PIR lamp will work as I have explained below: It will remain deactivated or disabled […]
High Efficiency Li-Ion LED Driver Circuits Explained
In this post I have explained a high efficiency 1.5 V to 4.2 V LED driver circuits which can be used with a standard Li-Ion battery for enhanced illumination, extended battery backup and long battery life. Main Features Using IC LT1932 The IC LT1932 is a fixed frequency step-up DC/DC converter intended to function as […]
Sound Activated LED Lamp Circuit
A highly sensitive sound activated LED lamp circuit can be built using just a few transistors and resistors. The circuit is actually a high gain MIC amplifier circuit which amplifies the external sound hitting the MIC. The amplified signal is then used to momentarily illuminate a bunch of LEDs. What does the Circuit do? Basically, […]





