Skip to main content

Battery Level Indicator


Battery Level Indicator
Here is the circuit diagram of a battery level indicator.This circuit is very simple and very cheap and compact.It can be used in transistor one band,two band or three band.This circuit is also
used in emergency lights and other power supply circuits.
Battery levels,normal or are indicated by the green or red LED repectively.One can set the circuit for monitoring the level of the battery within 3 to 10V with the help of 10k preset.
Transistor T1 is 'ON' due to the voltage divider biasing.Green LED is 'ON' as the collector of T1 is almost at ground.
When voltgae drops below the preset voltage,T1 switches off as the voltage is not sufficient to bias it to "ON" state.But the voltage at the base of T2 is sufficient to switch on T2 to conduction. Thus red LED glows-indicating the under voltage state of the battery

Comments

Popular posts from this blog

NE566 Function Generator Circuit Diagram

The NE566 Function Generator is a Voltage-Controlled Oscillator of exceptional linearity with buf fered square wave and triangle wave outputs. The frequency of oscillation is determined by an external resistor and capacitor and the voltage applied to the control terminal. The Oscillator CAN be programmed over a ten-to-one frequency range by proper selection of an external resistance and modulated over a ten-to-one range by the control voltage, with exceptional linearity.  FMAX = 1 MHz     WIDE 1000:1 Continuous Sweep Possible  NE566 Function Generator Circuit Diagram Pdf Datasheet  Sourced by : Circuitsstream

TDA2030 complete tone control

At this time I present a series of amplifiers that use IC TDA2030, but this series is equipped with a tone control. Tone controls include Bass, Treebel, and Volume. Power amplifier and tone control has been put together in a single PCB. As well as its power supply circuit was also used as one with the power amp, and tone control. Making it easier in the installation and will look neat. Schematics Layout PCB PCB design This amplifier is a mono amplifier type, can be modif for guitar amplifiers. If not coupled amplifier (mic preamp) then you must deactivated potensio treble and bass, why? because if not using a mic preamp and still maintain potensio treble and bass sound input (input) from the guitar will not or the maximum discharge is not tight on the speakers. So you must deactivated a way to decide which directly connected capacitor with the tone control circuit, and capacitor were connected directly to potensio volume and input jack.

Simple Preamplifier and High to Low impedance Converter Circuit Diagram

This is the Simple Preamplifier and High to Low impedance Converter Circuit Diagram. This circuit matches the very high impedance of ceramic cartridges, unity gain, and low impedance output.  Simple Preamplifier and High to Low impedance Converter Circuit Diagram By `loading` the cartridge with a 2M2 input resistance, the cartridge characteristics are such as to quite closely compensate for the RIAA recording curve. The output from this preamp may be fed to a level pot for mixing. Sourced By: Circuitsproject