![]() For dot display- Leave the pin 9 (mode selector pin) open.Īnd if you want to cascade more LM 3914 IC than connect pin 9 of first IC to pin1 of next LM3914Ĭontinue connecting pin 9 of lower input drivers to pin 1 of higher input drivers for 30, 40, or more LED displays. For Bar graph display- Connect pin 9 directly to pin 3(supply voltage pin)Ģ. If you want the change the dot display to bar display just incorporate following changes-ġ. Similarly connect yellow LED’s (LED4 to LED6) this will indicate battery capacity of 40 to 70 percent and remaining you can use Green LED. You can also connect different color LED for obtaining the status like connect RED LED’s as it is the sign of danger (LED 1 to LED3) which will indicate that that voltage level is less than 40 percentage and need to be taken care. And now by seeing the number of LED’s glowing you can easily calculate the status. Connect it to voltage from any battery to be tested at the input which will become power source for the circuit. If above phenomenon is happening your circuit is ready is use. Following table will show the voltage level when different LED will glow – Now, increase the input voltage in steps of 1.2V and see LED2 will glow in 2.4V and similarly increase the voltage in steps of 1.2V and LED3 will glow and so on. ![]() It will support wide temperature range from 0 degree to +70 degree Celsius.įor calibrating the circuit, apply the power supply and adjusts VR1 so that LED1 just start glowing. In this we do not require resistor with the LED’s because current drive to LED’s is regulated and programmed.Ħ. This IC can also work on 3V power supply.ĥ. You can cascade more IC’s up to 100 steps.Ĥ. This IC can drive LED’s, LCD or vacuum fluorescent display.ģ. ![]() In this user can easily select the dot or bar graph display just by changing a single pin.Ģ. LM3914 is a monolithic integrated circuit which senses the analog voltage and derives 10 LED’s providing a linear analog display.ġ. ![]() This simple battery level indicator circuit is based on single IC LM3914 with few more discrete components. 1: Prototype of Battery Level Indicator Circuit on Breadboard Advantage of this circuit is it does not require power supply it will take power supply from the battery of the device itself.įig. So before your battery dies you can recharge it. You can use this battery level indicator circuit with your inverter or with your car battery it will give you indication about your battery status. For example four LED's are glowing means battery capacity is 40 percent. Battery level indicator will let you know the status of battery of a device just by glowing the number of LED's. ![]()
0 Comments
Leave a Reply. |