US 11,942,927 B2
Method and device for short-circuit detection by saturation detection in power semiconductor switches
Calin Purcarea, Muehlacker (DE); Daniel Schweiker, Ludwigsburg (DE); Deepa Mathai, Stuttgart (DE); and Falko Friese, Ludwigsburg (DE)
Assigned to Robert Bosch GmbH, Stuttgart (DE)
Appl. No. 17/638,261
Filed by Robert Bosch GmbH, Stuttgart (DE)
PCT Filed Aug. 13, 2020, PCT No. PCT/EP2020/072789
§ 371(c)(1), (2) Date Feb. 25, 2022,
PCT Pub. No. WO2021/037580, PCT Pub. Date Mar. 4, 2021.
Claims priority of application No. 10 2019 212 889.0 (DE), filed on Aug. 28, 2019.
Prior Publication US 2022/0294441 A1, Sep. 15, 2022
Int. Cl. H03K 17/082 (2006.01); H03K 17/0812 (2006.01); H03K 17/18 (2006.01)
CPC H03K 17/0828 (2013.01) [H03K 17/08128 (2013.01); H03K 17/0822 (2013.01); H03K 17/18 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method for short-circuit detection by saturation detection in power semiconductor switches, comprising the following steps:
providing (1) a reference voltage (Uref) depending on a supply voltage (UVDD) of a power semiconductor switch (20), with the result that the reference voltage (Uref) follows changes in the supply voltage (UVDD);
generating (2) a differential voltage (Udiff) which corresponds to a difference between a voltage drop (UΔ) across a load path of the power semiconductor switch (20) and the provided reference voltage (Uref);
comparing (3) the generated differential voltage (Udiff) with a predetermined limit voltage (Ulim), wherein a short-circuit current is detected in the load path of the power semiconductor switch (20) when the differential voltage (Udiff) exceeds the limit voltage (Ulim); and
opening (4) the power semiconductor switch (20) when a short-circuit current has been detected in the load path of the power semiconductor switch (20).