I have successfully used the BQ24630 and BQ24133 in previous product applications and am now planning to use the BQ24610, but have a general question.
The BQ24610 looks attractive because it can manage up to 32V of adapter input voltage. My proposed application is to manage a 24V+-10% input adapter and a single cell LiCo battery driving a buck boost converter that holds 5V system power during normal operations and battery back-up in a system sleep-mode.
Like the BQ24630, there are internal Vcc-6V P-channel gate drives to control the ACDRV and BATDRV . However. unlike the BQ24133, the BQ24630 and BQ24610 devices must remain active to keep the P-channel gate drives under control. I believe this is done with a 10ohm resistor tied between the sources of the input back-to-back P-channels and device Vcc so the IC's Vcc is always available regardless of the adapter being present or the battery being switched in when the adapter is removed.
Normal operating specification for the BQ24610's Vcc is 5V to 28V. This is adequately supported when the 24V adapter is present, BUT when put in single cell LiCo battery mode only 4.2V max can be provided, and if depleted while in system sleep mode can be is low as 3.0V, before the input 24V adapter may reappear. Unlike the BQ24133, the BQ24610 p-channel gate drives must be active via Vcc to keep the battery switched to system power. This conflicts with the typical single cell LiCo battery output voltage being below 5V.
How does the BQ24610 power path behave when using a single cell LiCo battery?,,,,,,,,,,,,,,,,Jim Del Signore
