US 11,703,897 B2
LDO overshoot protection in a cascaded architecture
Michel Cuenca, Septemes les Vallons (FR); Bruno Gailhard, Rognes (FR); and Daniele Mangano, San Gregorio di Catania (IT)
Assigned to STMicroelectronics S.r.l., Agrate Brianza (IT); and STMicroelectronics (Rousset) SAS, Rousset (FR)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT); and STMicroelectronics (Rousset) SAS, Rousset (FR)
Filed on Mar. 5, 2020, as Appl. No. 16/810,639.
Prior Publication US 2021/0278868 A1, Sep. 9, 2021
Int. Cl. G05F 1/56 (2006.01)
CPC G05F 1/56 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method comprising:
receiving a main supply voltage;
generating a first regulated output voltage with a DC-DC converter;
providing the main supply voltage to a supply terminal of a driver, the driver having an output coupled to a control terminal of an output transistor of an LDO, the main supply voltage used to power the driver, the LDO having an input terminal coupled to a first current path terminal of the output transistor, and an output terminal coupled to second current path terminal of the output transistor;
receiving, at the input terminal of the LDO, the first regulated output voltage;
generating, at the output terminal of the LDO, a second regulated output voltage from the first regulated output voltage; and
in response to the main supply voltage falling below a predetermined threshold, discharging a capacitor coupled to the input terminal of the LDO by activating a switch coupled to the input terminal of the LDO.