SLUSDQ4 April 2019 BQ79606A-Q1
REF1 and REF2 are precision references used by the BQ79606A-Q1 to achieve high performance. REF1 is used for the ADC functions as well as providing the TSREF reference. REF2 is used for the protector functionality and used to check accuracy and diagnostics. REF1 is active whenever the BQ79606A-Q1 is in ACTIVE mode and REF2 is active in both SLEEP and ACTIVE. The REF1 reference is not active in SLEEP mode however the REF1 pin is powered from the AVDD through an internal voltage divider.
An oscillation detector monitors REF1 and sets the SYS_FAULT2[REF1_OSC] bit whenever it senses a REF1 oscillation. To avoid false trips during startup, the oscillation detection is disabled for the first 10ms of REF1 startup (IC transitions into ACTIVE state).
Contact TI Sales Associate or Applications Engineer for further information about long term drift.