Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
dinofx said:Is there an easy way to display voltage range from 0-12, or 6-12, using a 10 bar LED? The LM3914 seems to be archaic, and a bit of a hassle to combine with a separate LED bar.
Doesn't someone make a single part that combines the LED bars with the IC?
Nigel Goodwin said:dinofx said:Is there an easy way to display voltage range from 0-12, or 6-12, using a 10 bar LED? The LM3914 seems to be archaic, and a bit of a hassle to combine with a separate LED bar.
Doesn't someone make a single part that combines the LED bars with the IC?
Certainly at one time you could buy LM3914's incorporated into an LED bar, using COB (Chip On Board) technology - but I can't say I've looked for them at all recently!.
Nigel Goodwin said:Certainly at one time you could buy LM3914's incorporated into an LED bar, using COB (Chip On Board) technology - but I can't say I've looked for them at all recently!.
audioguru said:I didn't use dim, dinky little surface-mount LEDs on my latest project:
Thanks.justDIY said:audioguru said:I didn't use dim, dinky little surface-mount LEDs on my latest project:
nice looking
I just suggested surface mount since the OP apparently is concerned about space, wanting an entire voltage readout solution no bigger than a 20 pin DIP
The outputs of the microcontroller and the transistors are driving the LEDs. The grid is arranged so that each of the 20 LEDs or any number of LEDs can be lighted by using only 5 signal wires, since the microcontroller has only a few pins.dinofx said:I'm not sure I understand that last schematic. What is driving the LEDs? Why are they laid out in a grid vs. a single column?
dinofx said:I still don't see how this works. With 5 wires, there's 32 combinations. With just 10 LEDs there are 1024 possible lighting combinations. Does anyone have a link to define "charieplexing"?
dinofx said:Do pulsed LEDs emit as much light as a constantly power LED? I guess that's the part tricked me; I thought pulsing at 20% would appear dim.
Nigel Goodwin said:dinofx said:Do pulsed LEDs emit as much light as a constantly power LED? I guess that's the part tricked me; I thought pulsing at 20% would appear dim.
It would appear dim at that, so you don't pulse it at 20% - for five channels you would pulse at 500% - so each channel gets 100%.