SBVS233B January 2016 – June 2021 TPS7A84
PRODUCTION DATA
Some applications may have transients that place the device into dropout, especially because this device is a high-current linear regulator. A typical application with these conditions requires setting VIN ≤ VDO in order to keep the device junction temperature within its specified operating range. A load transient or line transient in these conditions can place the device into dropout, such as a load transient from 1 A to 4 A at 1A/µs when operating with a VIN of 5.4- V and a VOUT of 5.0 V.
The load transient saturates the error amplifier output stage when the pass element is fully driven on, thus making the pass element function like a resistor from VIN to VOUT. The error amplifier response time to this load transient (IOUT = 4 A to 1 A at 1 A/µs) is limited because the error amplifier must first recover from saturation and then place the pass element back into active mode. During the recovery from the load transient, VOUT overshoots because the pass element is functioning as a resistor from VIN to VOUT. If operating under these conditions, apply a higher dc load or increase the output capacitance to reduce the overshoot because these solutions provide a path to dissipate the excess charge.