Here’s a simple low supply rail detection circuit that costs peanuts and takes just 20 minutes or so to make. Its power consumption is quite low, so it could easily be built into battery-powered devices. Instead of using an op amp, the circuit is built around three low-cost transistors (Q1-Q3). Diodes D1-D3 form a 1.8V [...]
Many blind and deaf-blind persons use portable electronic devices to assist their everyday lives but it is difficult for them to test the batteries used in this equipment. Talking voltmeters are available but there is no equivalent usable by deaf-blind persons. This battery tester uses vibration and a user-settable control to enable blind and deaf-blind [...]
The LED stick bright when volt of battery model to load new get agree lower 8.3V ( for battery 9V). Which be minimum value that can agree, be a signal know that battery, want to load new already. The circuit can modify to go to apply to transistor radio for is warn change battery the [...]
Entries (RSS)
Link electronics
Copyright © 2010. All rights reserved. Any circuit and content represented are property of owner.