Try using LM3914 dot/bar display driver IC. You can cascade them to give you up to a 100 segment display so 50 steps segments should be easy. If you have trouble working out how to use them drop me a line and I will draw up a circuit for you.
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An elephant is a mouse built to government specifications.
You would have to be a bit more specific about your needs.
It would be helpful to know if you intend all LEDs to be lit sequentially (rather than using dot mode), the precision you wish to use (what voltage step does a single LED represent) and specifications for the source to be monitored (ie: upper/lower voltage limits, AC or DC, output impedance).
FYI...Using an LM3914 in cascaded mode with all LEDs lighting up sequentially (rather than using dot mode) would draw 1A of current from the supply when all 50 LEDs are lit. This makes the LM3914 a poor choice in power sensitive applications. If dot mode is used the current draw is of no concern.
The current draw with 50 LEDs all turned on is going to be the same regardless of the way you drive them. With the LM3914 you can set the current going through the diodes so there is no reason that you couldn't add some circuitry that reduced the current when say LED 25 turned on.
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An elephant is a mouse built to government specifications.
Bar Graph Indicator
Re: bar graph indicator
