[DigiKey "Smart Manufacturing, Non-stop Happiness" Creative Competition] PICO_LAB Hardware Design 2: VM

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[DigiKey "Smart Manufacturing, Non-stop Happiness" Creative Competition] PICO_LAB Hardware Design 2: VM [Copy link]

 

Power input design dual interface:

DC2.5 and typec, wide range input 5~20V, typec requires a sink end protocol chip, here we use ch224, which can adjust the input voltage according to the output to improve efficiency, and also supports QC standards.

Because the number of IOs is insufficient, this design requires a fixed 12V voltage to take into account both high and low voltage outputs.

VM is the voltage measurement part (current measurement channel is also designed)

After all, PS also needs to measure the output voltage and current. Here we use TI's ADS131M04, which contains 4 independent 24-bit ADCs, a PGA at the front end, and a built-in ref, which has good flexibility and performance.

The output voltage of the PS part is measured directly by using the built-in ADC of PICO through the voltage divider resistor because the accuracy requirement is not high. The output current is connected to ADS131 because the dynamic range requirement is high.

The other three ADS131 measurement channels are two for voltage input measurement and one for current input measurement.

The voltage input is divided by resistors, buffered by lmv321 to increase the input impedance, and then enters ADS131.

The current input passes through the sampling resistor, amplified by INA180, and enters ADS131.

PCB board design is completed, 3D effect:

Debugging to be continued~~