STC12C5A60S2 drives LCD1602 voltage and ammeter

The circuit is relatively simple. It is an LM358 amplified current sample, which is sent to the STC microcontroller for AD conversion, and a 1602 meter is added for display. Made improvements to the proofreading process. The button calibration program also adds the function of displaying the power supply voltage and the second input voltage, which can be switched by pressing the button. It can display voltage, current, supply voltage, elapsed time, discharge capacity and other parameters, and comes with a calibration function. A 10-bit AD converter can only achieve 2% accuracy at best. It is sufficient for general applications. The most important thing is that it is low cost and can be built using the remaining components on hand.

The calibration method is as follows:
When the power is off, press and hold the button and then power on. In turn, accurately input 10 volts to VIN1 and press the button; input 3 amps of current, and then press the button; accurately input 10 volts to the second test point VIN2, and then press the button; accurately input 10 volts to the power supply, and then press the button to complete the calibration. .

Displays the supply voltage, No. 2 voltage.

front.

back