battery

The low power LED flasher by ICM7555
Normally, when you need to use LED display status of the battery 6V-12V. Just add a resistor in series only. It is easy and saving.
But not cool and consumes more power.
- The impression of a bright that continuously. I think that did not noticeable it.
- When the LED light as well So consumes too much energy. Although the LED need voltage is 1.8V only, but it uses too current is 15mA-20mA.
A wise choice.
- The LED flashes very prominent.
- Find out how to use current less than 1mA. When several ten years ago. I’ve used a LM3909 of LED Flasher/Oscillator IC. (View circuits that using this IC number.) It is built for a particular flashing light or low current led flasher so easy to make and includes a very small amount. But unfortunately. Now IC manufacturers stopped producing it.
But we also have the option of interest, may be better than. If you are familiar with the IC 555 is a relative of the family is ICM7555 (or 7555IPA) with the same features. However very low power consumption. Because the internal structure of CMOS, So works great.
You take a look that the circuit is easy like I said or not. As shown below. You see not wrong, it using only three pieces, it can make the LED to flashes. By pull current from the power supply is only 0.15mA. It is designed as a typical Stable multivibrators circuit. (If you do not understand see this web. We have several circuits)

Read more source: http://www.eleccircuit.com/battery-status-monitor-by-icm7555/

This simple and cheap 6 volt power supply circuit with 6V backup battery system.
The AC power 220V is entered to through input of transformer-T1 to reduce voltage as 9VAC, then wire connected to four diode D1-D4 as bridge rectifier became to 11VDC, then the current is filtered to dc voltage that low ripple output and then the voltage is regulated to 6VDC constant voltage by IC-KA7805( IC-7805 type) In normal it is used for 5 volt only but now we add two resistor to determined output voltage is 6 volt and passed through diode 1N4002-D6 to output is 6 volt.

Read more source: http://www.eleccircuit.com/6v-backup-battery-power-supply-regulator-with-ic-7805/

Dry cell battery charger

Easy dry cell charger with CMOS IC 4011 The dry cell charger circuit can be fully charged about 12 hours.When used with a 9 volt supply,the equipments in the circuit for the AA type cell.When using the C and D type cell, should reduce the value of the resistance Rx to be 68 ohms.In charge of the cell, you should not be charged

Dry Cell Battery Charger using LM741 and IC4011 This is Dry Cell Battery Charger Circuit. That can use charger battery get that about 12 hour. When apply to power supply 9 volt the equipment that fix in the circuit use for size battery AA. If use the size C or D should devalue of Resistor RX down be 68ohm and should not lead

Salt Water Battery About 13 years ago, I made a salt water battery to operate a single AA battery quartz clock. It ran for several months until I got tired of adding water to compensate for evaporation. The batttery consisted of 5 cells each producing about 300 millivolts. As I remember, I used 5 small olive jars filled

This circuit can use with power supply since 5 volt until 25 Volt. When voltage of power supply or battery agree come to lower location level keeps. It make LED bright show know. Although the circuit this use how many is the equipment not, but there is the stability and accurate in good moderately work. Because of use IC Voltage Detector 8211 that bring build be Voltage Comparator Circuit. Which have Voltage Comparator at certainly stay within the integrated circuit. Read more and view circuit diagram

Checking the status of your car battery (accumulator) should be easier with this circuit which measures the internal resistance of the battery. Pulses generated by the 555 are used to drive a dummy load and the AC voltage which develops across the battery gives an indication of its internal resistance: the lower the voltage the healthier the battery. The AC voltage is read out by means of a digital meter connected at the output.
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