US 12,292,469 B2
Current measuring circuit
Christian Djelassi-Tscheck, Villach (AT); Cristian Mihai Boianceanu, Bucharest (RO); and Michael Nelhiebel, Villach (AT)
Assigned to Infineon Technologies AG, Neubiberg (DE)
Filed by Infineon Technologies AG, Neubiberg (DE)
Filed on Dec. 2, 2022, as Appl. No. 18/061,168.
Claims priority of application No. 102021134029.2 (DE), filed on Dec. 21, 2021.
Prior Publication US 2023/0194595 A1, Jun. 22, 2023
Int. Cl. G01R 31/28 (2006.01)
CPC G01R 31/2879 (2013.01) [G01R 31/2856 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A circuit comprising:
a power transistor having a main current path connected between a first supply node and an output pin for connecting a load, wherein a resistance formed by a chip metallization is coupled in series between the main current path of the power transistor and the output pin;
a current measuring circuit coupled to the power transistor and comprising a sense transistor coupled to the power transistor, wherein the current measuring circuit is configured to deliver a measurement current representing a load current flowing through the power transistor;
an amplifier circuit configured to generate an amplifier output signal representing a voltage across the resistance; and
a control circuit configured, by electronic switches, to output a signal representing the measurement current in a first mode and a signal dependent on the amplifier output signal in a second mode.