Hello everyone. I want to make a simple circuit that blinks 4 LED by using NE555. I need it to be really small circuit so i thought using a CR2032 coin battery would be compitable. I draw a circuit on Proteus which is perfectly working. But when I try to build the circuit the LED's are not working.
So my question is, is there any way to make this circuit more simple? Or make it compitable for CR2032?
@ovoup
The NE555 will not work on 3V.
You need to use a LMC555 or TLC555C or ICM7555
Best choice is the ICM7555
Or better still use a PP3 (6LR61) 9V battery that will give good results and last longer.
Yes, both answers are accurate. It's my fault to not look at the datasheet of NE555. I'm thinking to use 2 CR2032 batteries which is enough for NE555.
A PP3 will definetly work.
I recall building a flashing LED circuit with a NE555\PP3 into a wool hat in circa 1977.
Most people in those days though someone wearing a hat with flashing lights was weird, although they were no where near the brightness of modern LEDs.
Everyone assumed the 'lights' were small bulbs.
I still do
My current one is a red and white santa hat with a remote controlled WS2812 strip in the white rim of the hat. Its very bright, driven by a 2S Lipo.
Wear it at night and no torch is needed.
Just barely enough.
The ICM7555 uses much less current than the NE555 and can work down to 2V.
CR2032 are rated 220mAh
if you assume the LEDs draw a total of 50mA you can expect a useful life of about 3-4 hours.
Also the LEDs will have a forward voltage of about 2.5V so as the cell voltage drops they will dim.
thank you for the advice but unfortunately I've no ICM7555 any for the moment. need to order one first.
I'm plannig to make a pair of blinker gloves for night rides with my bicycle. The point is making a open circuit which is will be a completed circuit when i make a fist. So 3-4 hours of battery life is enough maybe for 2 weeks or longer.
There are self-blinking LEDs available, no external circuitry other than a current limiting resistor needed. That's the easiest way to do this.
Four of them will go out of sync very quickly of course, for better or for worse 
The CR2032 really is not a good choice here.
It has a plausible capacity, but not the ability to attain the specified capacity if you put a large load on it. Which is relative.
Battery life will depend on the load and how and when it is being asked to deliver current.
See
and decide if your use case is plausible. That manufacturer specifies 6 mA continuous maximum curretn, with 20 mA hits lasting one second as another maximum.
Go beyond that and calculations around battery life have less meaning.
Switch to Lipo cells. They can be had in a bewildering variety of sizes and capacities, deliver very well on higher current demands and can be easily recharged.
Use two, maybe and a buck regulator for a five volts system. Or use one and design around counting on good 3.3 volts well into the discharge area of a Lipo cell.
Ditch the CR2032, don't go broke buying new ones alla time.
a7
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.
