The Nordic Thingy:53™ kit comes with a current measurement and debug board that can be inserted into the P9 connector on the Nordic Thingy:53.
The current measurement and debug board simplifies the current consumption measurement of the four different power domains with a power profiling tool, such as the Power Profiler Kit II. The interface also enables a trace debugging functionality and the possibility to connect external circuits or boards to the Nordic Thingy:53 by using the TRACE pins as regular General-Purpose Input/Output (GPIO)s. The pins are configured as GPIOs by default.
It is recommended to connect external loads to VOUTB or 3V3. The maximum load on VOUTB is 150 mA. The maximum allowed current drawn by external circuitry on VOUTB depends on the total internal current draw. The maximum load on the 3V3 rail is 300 mA.
Thingy:53 v1.1.0 and higher have an automatic signal switching circuit as shown in the following figure. It replaces the SWDIO and SWDCLK pins on the P9 connector with P1.01 and P1.00. The signal switching circuit also disconnects P0.08 from the nPM1100 MODE pin. The signal switching circuit is only active when the nRF7002 EB is inserted into the P9 connector.
The following table describes the pinout of the P9 connector when the signal switching circuit is activated.
| I/O | Label | Description |
|---|---|---|
| 1 | VLi-Ion | Li-ion battery. Input to load switch U4. |
| 2 | V_Bat | Output from load switch U4. |
| 3 | VOUTB | nPM1100 Power Management Integrated Circuit (PMIC) VOUTB voltage domain. Configured to 3.0 V. |
| 4 | VDD_nRF5340 | nRF21540 RF FEM voltage supply. Output from load switch U5. |
| 5 | DBG.PIN5 | General Purpose IO (P1.01). |
| 6 | DBG.PIN6 | General Purpose IO (P1.00). |
| 7 | RESET | Reset line for the nRF5340 SoC. |
| 8 | EXP_BOARD_PIN1 | GPIO/Inter-integrated Circuit (I2C) SDA line for external boards. |
| 9 | EXP_BOARD_PIN2 | GPIO/I2C SCL line for external boards. |
| 10 | LOAD_SW_DISABLE | Load switch disable signal. Connected to ground when current measurement and debug board is inserted. |
| 11 | VOUTB | nPM1100 PMIC VOUTB voltage domain. Configured to 3.0 V. |
| 12 | VDD_nRF21540 | nRF21540 RF FEM voltage supply. Output from load switch U11. |
| 13 | VDD_EXP_BRD | External board voltage supply. Output from load switch U14. |
| 14 | 3V3 | 3.3 V regulator output. |
| 15 | TRACE3 | Trace data line 3/P0.08. |
| 16 | TRACE2 | Trace data line 2/P0.09. |
| 17 | TRACE1 | Trace data line 1/P0.10. |
| 18 | TRACE0 | Trace data line 0/P0.11. |
| 19 | CLK | Trace clock line for the nRF5340 SoC/P0.12. |
| 20 | Ground | Ground. |