SLUSDV2A May 2020 – May 2021 BQ25798
Figure 8-1 shows that an HVDCP source is first qualified as a DCP source in the USB BC1.2 standard detection stage, then qualified in the following HVDCP detection stage as an HVDCP source. When the HVDCP is first qualified as a DCP, the charger sets an IINDPM limit of 3.25A. The IIDPM is then updated to the HVDCP limit of 1.5A after the HVDCP handshake completes. In some cases the higher IINDPM limit of 3.25A may interfere with the source's ability to transition to 9V or 12V if the transition is attemped before the IINDPM is updated to 1.5A.
The recommended procedure for enabling detection of HVDCP sources is completed in the following steps: