JAJSQ69B december 2015 – may 2023 TPS65265
PRODUCTION DATA
The TPS65265 has dedicated enable pin and soft-start pin for each converter. The converter enable pins are biased by a current source that allows for easy sequencing by the addition of an external capacitor. Disabling the converter with an active pulldown transistor on the ENx pin allows for a predictable powerdown timing operation. The Figure 8-5 shows the timing diagram of a typical buck power-up sequence with connecting a capacitor at ENx pin.
A typical 1.4-µA current is charging ENx pin from input supply. When ENx pin voltage rise to typical 0.4 V, the internal V7V LDO turns on. A 2.9-µA pullup current is sourcing ENx. After ENx pin voltage reaches to ENx enabling threshold, 3.1-µA hysteresis current sources to the pin to improve noise sensitivity. After soft start time of 2.4 ms (typical), PGOOD monitor is enabled. If all output voltages are in the regulation and after PGOOD delay time, PGOOD is asserted.