Abstract: In a general aspect, a discharge circuit for discharging a voltage from a USB connector pin can include a discharge load configured to discharge the voltage from the pin. The discharge circuit can also include a first control circuit configured to adjust a magnitude of the discharge load during discharging, such that power consumption is less than or equal to a discharge power limit, and a discharge time is less than or equal to a discharge time limit. The discharge circuit can further include a second control circuit configured to detect whether the voltage of the pin is changed based on a first reference voltage during discharging and adjust the magnitude of the discharge load in response to the change in the voltage of the pin, such that a slew rate of the voltage is less than or equal to a slew rate limit.