CIRCUITRY FOR DETECTING A SHORT CIRCUIT OF A LOAD IN SERIES WITH AN FET

摘要

The voltage (UDS) on a power MOSFET (1) is compared with a voltage (UV) derived from the sum of the voltages of a Zener diode (3) and the threshold voltage (UT) of a second MOSFET (5) to detect a short circuit in a load (2) in series with the power MOSFET (1). When this total voltage is exceeded, the second MOSFET conducts. Its load current is then evaluated as the short circuit signal.