| 摘要 |
A control circuit for controlling a power supply is revealed. The control circuit is used to generate a switching signal for switching the power supply. The control circuit has a detection terminal for detecting a status of the power supply. A first protection circuit is coupled to the detection terminal and to receive a first detection signal via the detection terminal, and the first protection generates a limit signal in response to the first detection signal, for limiting output of the power supply. A second protection circuit is coupled to the detection terminal and to receive a detection signal via thereto, and the second protection generates a protecting signal, for cutting off the output of the power supply, in response to the first detection signal. A phase dividing circuit is coupled to the detection terminal, the first protection circuit and the second protection circuit, and to generate the first and second detection signal in response to the level of the switching signal, for achieving that two independently adjusted protection circuit are detected by one pin of an integrated circuit (IC) to prevent the IC from increasing of the pin amount. It further reduces the occupied area of the IC. |
| 主权项 |
1. A control circuit for controlling a power supply, for generating a switching signal to switch the power supply, the control circuit having a detection terminal for detecting the status of the power supply, the control circuit comprising:
a first protection circuit, coupled to the detection terminal, receiving a first detection signal via the detection terminal, the first protection circuit generating a limit signal in response to the first detection signal to limit output of the power supply; a second protection circuit, coupled to the detection terminal, receiving a second detection signal via the detection terminal, the second protection circuit generating a protection signal in response to the second detection signal to cut off the output of the power supply; a phase dividing circuit, coupled to the detection terminal, the first protection circuit and the second protection circuit, the phase dividing circuit generating the first detection signal and the second detection signal in response to the level of the switching signal; a logic unit, coupled to the first protection circuit and the second protection circuit, generating a reset signal in response to the limit signal and the protection signal; a flip-flop, coupled to the logic unit, generating the switching signal for switching the power supply in response to the reset signal; and a counting unit, coupled to the second protection circuit, generating a counting signal in response to the second protection signal and transferring the counting signal to the logic unit. |
