OVERCURRENT PROTECTION CIRCUIT AND SWITCHING CIRCUIT

• Main Authors: NOSAKA, Noriyuki, NAKADA, Hironori, IWAI, Satoshi
• Format: Patent
• Language: English; French; German
• Published: 08.05.2024
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; BASIC ELECTRONIC CIRCUITRY; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; PULSE TECHNIQUE

An overcurrent protection circuit is provided for a switching element turned on/off based on a control voltage. The overcurrent protection circuit includes a first transistor and a second transistor. The first transistor is a PNP bipolar transistor and has an emitter connected to the control voltage. The second transistor is an NPN bipolar transistor and has a base connected to a collector of the first transistor, a collector connected to a base of the first transistor and pulled up to a predetermined pull-up voltage, and a grounded emitter. When the control voltage exceeds a predetermined first threshold voltage, the first and second transistors are turned on, the control voltage is dropped by drop of the pull-up voltage, and thus the overcurrent protection circuit starts a protection operation of turning off the switching element.