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LED bar graph for throttle usage

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Cval

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Hey guys, so I'm using the LM3914 bar display driver for this. I have every thing hooked up via breadboard and it works. The only problem is the bike gives 0.65V closed throttle and 3.9V wide open, so right now there is one LED lit when the throttle is completely closed. How can I reduce the input voltage so that the 0.65V is actually 0V? I've tried putting a resistor in line with the input (throttle usage) voltage but nothing changes. Thanks.

The circuit, except I've changed R1 and R2 to read 0-3.9V
circuit.jpg
 

I think a resistor in series with the RLO pin would create the needed voltage drop so that the ref voltage of the last comparator increases.
The internal resistance is 10K so a 2k resistor should do what you want since the ref is 3.9v and (2k/(10k+2k)) * 3.9v = 0.65v

---------- Post added at 03:32 ---------- Previous post was at 03:24 ----------

My calculation was wrong becasue the last 1K (internal) resistor is before the comparator input so you need less than 1K on RLO pin.

I think a 820 ohm should do the job.
 

It works! Thank you so much.
 

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