Load supply control circuit for measuring load current to diagnose overload in electrical circuit of LED bulb used in instrument panel of car, has interconnection point between transistor and resistor and including measuring circuit output

摘要

The circuit has a measurement circuit (10) including two transistors (Q2, Q3) mounted in a current mirror. One of the transistors is mounted in a diode and connected in series with an output transistor (Q1), and the other transistor delivers image charging current to an output resistor (R1). The resistor is connected in series between the latter transistor and electric ground. An interconnection point between the latter transistor and resistor includes a measuring circuit output, where potential of output corresponds to measurement representative of charging current of a microcontroller (2).