Patent ID: 9413223
Filing Date: 2016-08-09
CPC Classification: H02M

Claim Text:
1. A boost apparatus adapted for providing a direct-current output voltage to a load, the boost apparatus comprising: a boost power conversion circuit configured to receive a direct-current input voltage and provide the direct-current output voltage to the load in response to a pulse-width-modulation signal, wherein the boost power conversion circuit comprises: a control chip coupled to the boost power conversion circuit, the control chip being configured to: generate the pulse-width-modulation signal to control an operation of the boost power conversion circuit; and stop outputting the pulse-width-modulation signal and enter into a shutdown state when the diode is open-circuited, so as to protect the boost apparatus and/or the load from being damaged, wherein if the boost apparatus is in a normal operation, and if the diode is open-circuited, a voltage drop across the third resistor is lower than a preset voltage, and thus the control chip continues outputting the pulse-width-modulation signal with a maximum duty cycle in response to the diode being open-circuited, and wherein if the voltage drop across the third resistor is kept lower than the preset voltage, and the pulse-width-modulation signal with the maximum duty cycle continues being output concurrently, then the control chip stops outputting the pulse-width-modulation signal and enters into the shutdown state.