Led ammeter

[xtrmi]

I would like to build a circuit that uses leds to indicate each unit of 1ma that is sourced from a power supply. So the first one will be lit when 1ma is drawn and the first and second will be lit when 2ma is drawn and so on. I'm not really wanting to do this with an adc. I tried some different things with transistors but it didn't work to well. Does anybody have any ideas or suggestions?

 

[RCinFLA]

**broken link removed**

 

[xtrmi]

Ok. sweet I'm a newb in this area. I was trying to use an array of resistors to control how much current was flowing into the base of a transistor. It didn't work to well but there were noticeable differences int he brightness of each led. Your suggestion will work. I will try my luck with some comparators.

 

[georgetwo]

this topic has been discussed before you might see some help here.

https://www.electro-tech-online.com/threads/led-ammeter-using-lm3914.92309/


well in my own view, you should not have used an led direct from the resistor. you would have used it to switch a transistor, in that case, there won't be any low display. it is either there is no output or there is (1 / 0), in each led.

 

[xtrmi]

I was trying to see if I could get that sort of 0/1 functionality by applying different levels of current to the base of a transistor. I haven't learned much about semiconductor devices and I was only messing around. But I do want this kind of display on my bench top so I know when its overloaded. Thanks for the tips. Also thanks RCinFLA for the big help on my other thread. So far that is the only solution given to my problem and it works very well.

Oh and sorry for this thread I didn't see it on Google so I assumed there wasn't any thread for this topic.