ZHCSPP3 July 2022 TPS563300
PRODUCTION DATA
The undervoltage lockout (UVLO) can be adjusted using the external voltage divider network of R1 and R2. R1 is connected between VIN and the EN pin of the TPS563300 and R2 is connected between EN and GND. The UVLO has two thresholds: one for power up when the input voltage is rising and one for power down or brownouts when the input voltage is falling. For the example design, the supply turns on and start switching when the input voltage increases above 8 V (VSTART). After the converter starts switching, it continues to do so until the input voltage falls below 7 V (VSTOP). Equation 2 and Equation 3 can be used to calculate the values for the upper and lower resistor values. For the stop voltages specified, the nearest standard resistor value for R1 is 511 kΩ and for R2 is 80.7 kΩ.