CC pin circuit of USB Type-C

Abstract

The invention provides a CC pin circuit of USB Type-C. In the Type-C interface circuit, a high-voltage NMOS is introduced for voltage isolation, and a first low-voltage region is generated. A pull-upresistor circuit, a CC connection detection circuit, a PD communication circuit and the like are placed in the first low-voltage region to realize high-voltage protection. The pull-down resistor circuit is directly connected to the CC pin, so that when the Type-C interface is in a Dead Battery state in a DRP or SNK mode, the CC connection can be normally realized by accessing the SRC or other DRPs(Data Redundancy Protocol). And a resistor in the pull-down resistor circuit is divided into a first resistor and a second resistor which are connected in series, and voltage clamping is performed ata middle series node to generate a second low-voltage region. And an enable control switch of the pull-down resistor circuit and the second resistor are placed in the second low-voltage region to realize high-voltage protection. The first resistor is placed in a high-voltage area and plays a role in current limiting when the voltage clamping circuit works. The withstand voltage design method andthe circuit structure can be applied to Type-of all modes. And in the C interface circuit, the voltage withstanding problem of the CC pin is solved.

Description

technical field [0001] The invention relates to the technical field of USB Type-C interface circuits, in particular to a CC pin circuit of USB Type-C. Background technique [0002] With the rapid development of electronic technology, portable electronic products represented by mobile phones, tablets and notebook computers have widely affected people's daily life. The new USB Type-C interface supports front and back insertion, which solves the worldwide problem of "USB can never be inserted correctly". In addition, compared with the traditional USB interface, the Type-C interface has the characteristics of lighter weight, thinner design, smaller size, and stronger expandable functionality, which is very suitable for application in portable electronic products. Since the Type-C interface came out, it has been widely popularized in just a few years. [0003] With the rise of USB fast charging technology, the voltage transmitted by VBUS in the USB interface is no longer a fixe...

AI Technical Summary

Problems solved by technology

At this time, connecting to SRC or other DRP cannot form a pull-down path connected to the CC pin. When the Rp_SRC resistor Ⅴ of the Type-C interface at the other end appears, it will pull up the voltage of the CC pin Ⅳ to the power supply of the Type-C interface at the other end. VDDSRC, so the CC connection cannot be realized, and the Type-C interface at the other end will not output VBUS, resulting in the dead battery state being unable to be activated.

This situation is often unacceptable in practical applications

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