SLUSDL4 February 2020 TPS59632-Q1
PRODUCTION DATA
PGOOD is an open-drain output pin that is designed to be pulled-up with an external resistor to a voltage 3.6 V or less. Normal PGOOD operation (exclusive of activation of any faults) is shown in Figure 7-8. On initial power-up PGOOD happens within 6 µs of the DAC reaching its target value. When EN is brought low, PGOOD is also brought low for 250 µs, then is allowed to float. The TPS59632-Q1 device pulls down the PGOOD signal when the EN signal subsequently goes high and returns high again within 6 µs of the end of the DAC ramp. The delay period between EN going high and PGOOD going low in this case is less than 1 µs. Figure 7-8 shows the power good operation at initial start-up and with falling and rising EN.
For applications where it is undesirable to have PGOOD high when EN is low, an alternate method of pulling up the open-drain PGOOD signal is possible. In this method, the PGOOD is pulled up to EN logic signal. This ensures that the PGOOD is low when EN goes low.