【LPC54100】+LPC54102 current consumption measurement circuit analysis

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【LPC54100】+LPC54102 current consumption measurement circuit analysis [Copy link]

When analyzing the LPC54102 development board, I found the current consumption measurement circuit of LPC54102. I will briefly analyze it and use it as a reference circuit in the future.

The LPC54102 development board has an external TI 12bit ADC--- ADC111S021, which is mainly used to test the power supply current consumption of LPC54102.

The main parameters and performance of ADC111S021 are as follows:

JP7 is the power selection connection of the main control chip. The default connection in the development board is 3.3V power supply. The measurement range of ADC111S021 is 0 to 3.3V, so 1 lsb = 3.3V/4096 = 805uA. The current measurement circuit in the development board is:

The resistor for measuring current is 8.2 ohms, and the 1 lsb current consumption given by lpc54102 is 3.9uA.

The current on R18 collected by the MAX9634TEUK chip is converted into voltage, and connected to ADC111S021 input 1 through the 2-to-1 selector 74LVC1G53DC. After AD conversion, it is converted into SPI data and read by LPC4322JET100. The actual screenshot of ADC111S021 is as follows.

The attachment is the manual of the relevant chip. My other experience posts: https://bbs.eeworld.com.cn/thread-457205-1-2.html