SDAA416 June   2026 BQ25672 , BQ25690 , BQ25790 , BQ25798

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Detailed Description
    1. 2.1 Circuit Operation
    2. 2.2 MOSFET Selection Considerations
    3. 2.3 Test Results
  6. 3Summary
  7. 4References

2.3 Test Results

The waveform in Figure 2Figure 2-2 shows the system entering and exiting ship mode.

PFET Entering and Exiting Ship Mode Figure 2-2 PFET Entering and Exiting Ship Mode

The PFET was TI's CSD25404Q3. RPU was 5MΩ and RSYS was 500Ω. Channel 1 (Yellow) shows simulated battery output voltage. Channel 2 (Blue) shows the voltage that BQ25790EVM BAT pin. Channel 3 (Pink) shows the simulated MCU's GPIO from a function generator. Channel 4 (Green) shows the PFET gate voltage. From the image we can observe that as the simulated GPIO output drops to 0V, the PFET gate voltage is pulled up, activating ship mode. We can confirm this by looking at channel 2, observing how the BQ25790 BAT pin voltage drops as the PFET gate rises. Lastly, as the GPIO rises back up to the original state, we observe that the PFET turns back on, reconnecting the simulated battery to the charger BAT pin.