This open-drain pin pulls LOW to indicate a good input source when:

1. VIN above V_{IN_LOWV}
2. VIN above V_OUT + V_SLEEPZ (not in SLEEP)
3. VIN below V_{IN_OV}

The PG pin can be used as the GND connection for the bottom resistor in the feedback divider to prevent divider leakage current from the supercapacitor when the charger is disabled. This is only recommended when V_REG ≤ 5 V (1-2s supercapacitors) as the absolute maximum rating on PG is 5.5 V. An example circuit can be seen in Figure 8-11.