# Variable High Power “Resistor” For Power Supply Testing

Schematic Diagrams      Comments Off on Variable High Power “Resistor” For Power Supply Testing

Current handling capability of a power supply system often needed to be checked. Finding high power rated variable resistor to provide variable load testing might be difficult. There is wire wound type but it’s not always available at your local store, and the price and performance might be disappointing. This… Read more »

# Battery Level Indicator

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A battery level indicator circuit is depicted in the schematic diagram below. This circuit is designed for 9V battery operation, as this circuit will start dimming below 7V and will be completely turned off at 6V.  If you want the LED indicator not to dimming but just abruptly turns off… Read more »

# Low Power Under- and Over-Voltage Monitor

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This voltage monitor has two  threshold, VTH for undervoltage and VTH’ for overvoltage. Using the component values shown in the schematic diagram below, this circuit give 6V for VTH and 15V for VTH1. Above 6V, the LED indicator of this voltage monitor  circuit will increase the flash rate until reach… Read more »

# LM10 Battery Voltage Threshold Indicator

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A battery threshold indicator circuit shown in the schematic diagram below has current regulation mechanism in driving the LED. A sufficient current should be satisfied at the minimum voltage but no excessive current when the voltage is at the highest level. Balance pin (5) is used as the reference  voltage… Read more »

# 1.5V to 9V Battery Tester

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Here the circuit diagram of DC battery tester designed by Matthew B.. This circuit can be used to measure DC battery from 1.5V up to 9V. Component Parts List: R1 = 18K Ohm R2 = 240 Ohm R3 = 8.2K Ohm R4 = 3K Ohm R5 = 10 Ohm M1… Read more »