This Voltage Reference Circuit. It used LM334 (ADJUSTABLE CURRENT SOURCES IC)
By fix the trend is stable. It make the pressure that pay to come out have tall stability. By can fine decorate VR1 10K Adjust Voltage Output. And You can use Voltage Input power supply at +2.5V to +20V. cause be high class voltage Output be valuable 0.8-5.0V depend on fining decorates VR1 there.
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