Patent ID: 7633274
Filing Date: 2009-12-15
Classification: H02M

Abstract:
1. A switching type power unit comprising: a voltage conversion circuit for outputting an output voltage by converting an input voltage to said output voltage in accordance with a switching signal supplied, but for outputting an output voltage close to said input voltage when said switching signal is not supplied; a control circuit for outputting said switching signal controlled in association with the voltage difference between a first detection voltage in accordance with said output voltage and a first reference voltage such that said first detection voltage becomes equal to said first reference voltage; and a malfunction detection circuit, adapted to compare a second detection voltage in accordance with said output voltage with a second reference voltage; and generate and supply to said control circuit a malfunction detection signal to stop supplying said switching signal when said second reference voltage exceeds said second detection voltage; wherein said second reference voltage is set to a level in accordance with the input voltage.