Electronic device with USB interface and method for starting USB communication therefor

摘要

The disclosure provides an electronic device with a Universal Serial Bus (USB) interface and a method for starting USB communication for a USB interface, so as to solve the problem that a mobile phone terminal device can be damaged easily when a charger shares one interface with USB communication in the conventional art. A control pin of the control circuit of the device is connected with a VCHG pin of a power management chip; an output pin of the control circuit is connected with a USB_VBUS pin of a USB interface chip; a power pin of the control circuit is connected with a fixed voltage input end which inputs a high level; and the control circuit is configured to output a fixed voltage from the output pin of the control circuit when detecting that the voltage of the control pin is more than a set threshold and output a low level from the output pin of the control circuit when detecting that the voltage of the control pin is less than the set threshold. The charging voltage (VCHG) of the handheld terminal product is only used as the control signal which is isolated from the voltage output to the USB_VBUS pin, so that the damage to the device is avoided.

主权项

1. An electronic device with a universal serial bus (USB) interface, comprising a power management chip, a USB interface chip and a control circuit, wherein the control circuit is connected with the power management chip and the USB interface chip respectively and adopts a charging voltage (VCHG) input to the power management chip as a control signal to output a voltage corresponding to the control signal to a USB power anode (USB_VBUS) pin of the USB interface chip, wherein the control signal and the voltage output to the USB_VBUS pin are mutually isolated.