SLVSBB4G August 2012 – June 2018 TPS54360
The Undervoltage Lockout (UVLO) can be adjusted using an external voltage divider on the EN terminal of the TPS54360. The UVLO has two thresholds, one for power up when the input voltage is rising and one for power down or brown outs when the input voltage is falling. For the example design, the supply should turn on and start switching once the input voltage increases above 8 V (UVLO start). After the regulator starts switching, it should continue to do so until the input voltage falls below 6.25 V (UVLO stop).
Programmable UVLO threshold voltages are set using the resistor divider of RUVLO1 and RUVLO2 between Vin and ground connected to the EN terminal. Equation 4 and Equation 5 calculate the resistance values necessary. For the example application, a 523 kΩ between Vin and EN (RUVLO1) and a 84.5 kΩ between EN and ground (RUVLO2) are required to produce the 8 V and 6.25 V start and stop voltages.