ZHCSIF0N September 2008 – October 2021 BQ24072 , BQ24073 , BQ24074 , BQ24075 , BQ24079
PRODUCTION DATA
The BQ2407x contains two open-drain outputs that signal its status. The PGOOD output signals when a valid input source is connected. PGOOD is low when (VBAT + VIN(DT)) < VIN < VOVP. When the input voltage is outside of this range, PGOOD is high impedance.
The charge cycle after power-up, CE going low, or exiting OVP is indicated with the CHG pin on (low - LED on), whereas all refresh (subsequent) charges will result in the CHG pin off (open - LED off). In addition, the CHG signals timer faults by flashing at approximately 2 Hz.
| INPUT STATE | PGOOD OUTPUT |
|---|---|
| VIN < VUVLO | High-impedance |
| VUVLO < VIN < VBAT + VIN(DT) | High-impedance |
| VBAT + VIN(DT) < VIN < VOVP | Low |
| VIN > VOVP | High-impedance |
| CHARGE STATE | CHG OUTPUT |
|---|---|
| Charging | Low (for first charge cycle) |
| Charging suspended by thermal loop | |
| Safety timers expired | Flashing at 2 Hz |
| Charging done | High-impedance |
| Recharging after termination | |
| IC disabled or no valid input power | |
| Battery absent |