18.104.22.168 QON Pin Operations
The QON pin incorporates two functions to control BATFET.
- BATFET Enable: A QON logic transition from high to low with longer than tSHIPMODE deglitch turns on BATFET and exit shipping mode. When exiting shipping mode, HIZ is enabled (EN_HIZ = 1) as well. HIZ can be disabled (EN_HIZ = 0) by the host after exiting shipping mode. OTG cannot be enabled (OTG_CONFIG = 1) until HIZ is disabled.
- BATFET Reset: When QON is driven to logic low by at least tQON_RST while adapter is not plugged in (and BATFET_DIS = 0), the BATFET is turned off for tBATFET_RST. The BATFET is re-enabled after tBATFET_RST duration. This function allows systems connected to SYS to have power-on-reset. This function can be disabled by setting BATFET_RST_EN bit to 0.
Figure 18 shows the sample external configurations for each.
Figure 18. QON Timing
Figure 19. QON Circuit