LM3914 expanded range for low voltages

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M0GJD

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I would like to use an LM3914 display driver to monitor the outputs from sensors that have a range from 0.1 to 0.9 volts so in simple terms a 0.0 to 1.0 volt readout in steps of 0.1 volt would be ideal.

I can find plenty of information on using the LM3914 for expanded ranges that are well above the internal reference source -there are examples in the National Semiconductor data sheet itself- but nothing about expanded range displays for small voltages.

I would be grateful for any guidance as to how the job can be done and an idea of how to calculate the required component values.

Thank you.
 
Spec. it; what small voltage in for what indication out [the Vin/Vout curve], plus any other constraints (tempco, accuracy, etc.)?
 
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The LM3914 can be set to 1.25 volts full scale by;
ADJ=0 volts, connect RefOut to RHI. (RefOut=1.25 volts)

To make full scale=1.0 volts add a 2.5k resistor from RefOut to RHI. Now RHI=1 volt.
 
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