US 12,279,350 B2
LED array driver with channel to channel and channel to ground external PIN short detection
Maria Francesca Seminara, Catania (IT); and Salvatore Rosario Musumeci, Fiumefreddo di Sic (IT)
Assigned to STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on May 23, 2024, as Appl. No. 18/672,975.
Application 18/672,975 is a division of application No. 17/826,461, filed on May 27, 2022, granted, now 12,028,949.
Prior Publication US 2024/0314909 A1, Sep. 19, 2024
Int. Cl. H05B 45/30 (2020.01); H05B 45/46 (2020.01); H05B 45/50 (2022.01); H05B 45/54 (2020.01)
CPC H05B 45/54 (2020.01) [H05B 45/46 (2020.01)] 20 Claims
OG exemplary drawing
 
1. A light emitting diode (LED) lighting system, comprising:
a plurality of strings of LEDs;
an LED driver chip comprising a plurality of driver circuits, each coupled to a different one of the plurality of strings of LEDs via a respective pin;
wherein each of the plurality of driver circuits includes a fault detection circuit for that driver circuit;
wherein each fault detection circuit comprises a force circuit including a current sourcing circuit configured to source a forcing current to a force output node;
wherein each fault detection circuit further comprises a sense circuit, each sense circuit comprises:
a current sensor coupled to the force output node; and
a comparator configured to compare a voltage at the force output node to a reference voltage and generate a comparison output based thereupon; and
control circuitry configured, in a pin-to-pin short detection mode, to:
activate the force circuit of a first given one of the plurality of driver circuits;
activate the sense circuit of a second given one of the plurality of driver circuits; and
when the comparison output of the comparator of the activated sense circuit indicates that the voltage at its force output node is greater than the reference voltage, indicate presence of a short between the respective pin for the first given one of the plurality of driver circuits and the respective pin for the second given one of the plurality of driver circuits.