In this blog, we describe how are our boards are hardware tested after prototypes are available. This testing is done to ensure that the boards designed work and work as per requirements.
The ESP32 click Board described here would be tested and its bring-up would be shown. Here is the block diagram of the board:
Here are some of the bring-up steps followed for testing:
1. Visual inspection: Quick check to ensure that all components are soldered as per the orientation and visual shorts exist.
2. Power check: Quick power test on the PCB to check for open short test. Using the multimeter to quickly test the 3.3V and 5V supply.
3. USB connection: USB cable was connected to the J10 port. 5V and 3.3V supply was good on the board and coming at test points. Checked on oscilloscope to measure voltage ripple which is under 5%.
4. Reset check: The reset was asserted and de-asserted by TPS3895 as expected.
5. FT232 Driver detection: The device was quickly found on the laptop and the driver was easily found on the web. This indicates that the USB to UART device ft232 is functioning correctly.
6. ESP32 detection: The factory programmed ESP32 comes with the Wifi stack and can be easily detected as the WIFI host with the name ESP32. If the ESP32 is out of reset it would show esp32 wifi LAN which can be connected to. It again indicates it is alive and functional.
7. LED programming: Ardunio was selected to test the board as it is easy to program and most of the drivers are easily available. Programmed the LED program to test the led and also testing the programming sequence of JP1.
8. Switch detection: Next quick program which detects switch press and led lighting up.
9. Mounting the Click board: Mounted the ADXL345 accelerometer from Mikro Electronica on the click connector. The LED on accel click switches on and the supply stays stable for 3.3v and 5v.
10. Testing of i2c interface: Detected the device at 0x1d. Read through the register values and moved the boards to check the accelerometer output.
11. Testing of spi interface: Changed the Mikroe Accell click board to spi mode and tested the spi operation on the board using ESP32 module.
12. Testing other examples with esp32: The board was tested with other software examples specified at the Sparkfun website to check for power, operation, and functionality.
13. Testing of battery charging and functionality. The battery of 220mA was connected to the battery connector and charged. The voltage was measured on the port. Shortly afterward the battery-powered operation was tested.
Bring up and the testing of the board were fun and quite enriching as with each board it brings pleasure to see circuit tree platform getting mature.