ZHCSIH1A July 2018 – September 2019 TPS56637
PRODUCTION DATA.
The TPS56637 has a built in power good (PG) function to indicate whether the output voltage has reached its appropriate level or not. The PG signal can be used for startup sequencing of multiple rails. The PG pin is an open-drain output that requires a pull-up resistor (to any voltage below 5.5 V). A pull-up resistor of 100kΩ is recommended to pull it up to 5V voltage. It can sink 1.5mA of current and maintain its specified logic low level. Once the FB pin voltage is between 90% and 110% of the internal reference voltage (VREF) and after a deglitch time of 64µs, the PG turns to high impedance status. The PG pin is pulled low after a deglitch time of 32µs when FB pin voltage is lower than 85% of the internal reference voltage or greater than 115% of the internal reference voltage, or in events of thermal shutdown, EN shutdown, UVLO conditions. VIN must remain present for the PG pin to stay Low.
| Device State | PG Logic Status | ||
|---|---|---|---|
| High Impedance | Low | ||
| Enable (EN=High) | VFB doesn't trigger VPGTH | √ | |
| VFB triggers VPGTH | √ | ||
| Shutdown (EN=Low) | √ | ||
| UVLO | 2 V < VIN < VUVLO | √ | |
| Thermal Shutdown | TJ > TSD | √ | |
| Power Supply Removal | VIN < 2 V | √ | |