Large discrepancy between PPK2 Source Meter and Ampere Meter measurements in sleep mode

[Shimi Hersh]

Hello,

I am measuring the sleep current consumption of a custom board using the PPK2, and I am observing a significant discrepancy between the two measurement modes.

• Source Meter mode: ~33 µA average current
• Ampere Meter mode (external battery): ~1 mA average current

This is a ~30× difference, while the system is expected to be in the same sleep state in both cases.

Additional details:

• Same firmware and configuration
• Same hardware (custom board)
• No intentional changes between measurements
• Setups and measurement screenshots are attached

I would like to understand what could cause such a large gap between the two modes.

               AM - setup                                                              SM - setup

.                      

                                      AM - result                                                                             SM - result

[Kenneth]

Hello,

What is the voltage level from that battery I see there? Do you see the same if you using a steady power supply (bench supply)? What is the voltage used in source mode?

Kenneth