Supply Current Measurement

The current consumption of the TA100 device can be measured by using the AC164166 14-Pin SOIC socket board. The only devices on the board that will consume power are the TA100 socketed device, the Power LED and the I²C pull-up resistors. Follow these steps to measure the current:

1.Modify the board to remove the resistor, R1, which is in series with the LED. This will remove the current through the LED from the total measured current.⁽¹⁾
2.Install the TA100 device into the socket.
3.Install the socket board into the host system with the appropriate power settings.
4.Select either 3.3V or 5V power for the measurement.⁽²⁾
5.Connect the high side of the ammeter to the 3.3V or 5V supply.
6.Connect the low side of the ammeter to the common PWR signal of the header.
7.Current measurements can now be taken by running various TA100 commands and measuring the current. ⁽³⁾

Notes:

1.For lower accuracy current measurements, this resistor may be kept in the circuit. It is recommended that a separate measurement of the current through just the LED path be made prior to measuring the TA100 device currents. This value can, then, be subtracted from the total current measured.
2.The host board provides power to the mikroBUS extension board, so whichever supply is selected must match the capabilities and setting used on the host board.
3.When measuring the current of I²C devices, the measurement will include the I²C pull-up currents used to pull up the bus. For SPI signals, the pull-ups are internal to the device and will also factor into the total current consumed.