Main loop of switching power supply of multifunctional composite lamp

The utility model discloses a multifunctional composite lamp switching power supply main loop, which relates to the technical field of automobile manufacturing, and comprises a switching power supply chip U4, and a BOOT pin of the switching power supply chip U4 is connected with a capacitor C16 and then is connected with a PH pin of the switching power supply chip U4; a VIN pin of the switching power supply chip U4 is connected with a + 24Vzx end; an EN pin of the switching power supply chip U4 is connected with an OFFZX end; an SS/TR pin of the switching power supply chip U4 is connected with a capacitor C24 and then is grounded GND; the RT/CLK pin of the switching power supply chip U4 is connected with a resistor R30 and then is grounded GND; a PH pin of the switching power supply chip U4 is connected with an inductor L3 and then is connected with a ZX9V end; and a COMP pin of the switching power supply chip U4 is sequentially connected with a resistor R31 and a capacitor C26 and then is grounded GND. The i