A TYPE C circuit without PD chip

Abstract

The present invention relates to a TYPE C circuit without a PD chip, which includes a TYPE C interface; an external charging circuit, whose voltage output end is connected to the VBUS end of the TYPE C interface for power supply; a TYPE C VBUS detection circuit, whose input end is connected to the VBUS end of the TYPE C interface for VBUS detection and control; a SUB / AUX switching circuit, whose input end is connected to the SUB pin of the TYPE C interface for converting a DP signal into an AUX signal when the TYPEC is inserted forward and backward; a CC mis-discharge circuit, whose input end is connected to the CC pin of the TYPE C interface for discharge protection; a CC detection circuit, whose input end is connected to the CC mis-discharge circuit output end for CC pin signal state detection of TYPE C; a SCALER chip, whose DP end is connected to the TX / RX port of the TYPE C interface, the CC detection circuit output end is connected to the ADC end of the SCALER chip, and the SUB / AUX switching circuit output end is connected to the SCALER chip input end for signal transmission control. This circuit has a simple periphery and low cost, and solves the CC communication problem.

Description

Technical Field

[0001] The invention relates to the field of TYPE-C technology, in particular to a TYPE C circuit without a PD chip. Background Art

[0002] At present, with the rise of TYPE C products in recent years, more and more monitors have also applied TYPE-C interface technology. As TYPE C is increasingly widely used, more and more monitors are equipped with TYPE C ports. Then, TYPE C must be equipped with at least one PD chip to implement the CC communication protocol of the TYPE C port. The cost of PD chips is relatively high, which is more than 10% higher for mid- and low-end monitor boards, which is difficult for customers to accept. The cost of existing TYPE C circuits with PD chips is high.

[0003] Therefore, a TYPE C circuit without a PD chip is provided to solve the CC communication problem. Summary of the invention

[0004] The purpose of the present invention is to provide a TYPE C circuit without a PD chip to solve the CC communication problem.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a TYPE C circuit without a PD chip, comprising:

[0006] TYPE C interface;

[0007] The voltage output end of the external charging circuit is connected to the VBUS end of the TYPE C interface for power supply;

[0008] TYPE C VBUS detection circuit, whose input end is connected to the VBUS end of the TYPE C interface, is used for VBUS detection and control;

[0009] The SUB / AUX switching circuit has an input end connected to the SUB pin of the TYPE C interface and is used to convert the DP signal into the AUX signal when the TYPE C is inserted forward or reversely;

[0010] The CC mis-discharge circuit has an input end connected to the CC pin of the TYPE C interface for discharge protection;

[0011] A CC detection circuit, whose input end is connected to the output end of the CC mis-discharge circuit, is used for detecting the signal state of the CC terminal of TYPE C;

[0012] The SCALER chip has its DP end connected to the TX / RX port of the TYPE C interface, the CC detection circuit output end connected to the ADC end of the SCALER chip, and the SUB / AUX switching circuit output end connected to the SCALER chip input end, which is used for signal transmission control.

[0013] Furthermore, the TYPE C VBUS detection circuit includes a resistor R206, a resistor R207, a resistor R208, a capacitor C154 and a MOS tube Q24; one end of the resistor R206 is connected to the VBUS end of the TYPE C interface, and the other end is connected to the resistor R207 and then grounded; the drain of the MOS tube Q24 is connected to +3V3, the gate is connected to the common connection point of the resistor R206 and the resistor R207, the source is connected to the capacitor C154 and then grounded, the source is connected to the resistor R208 and then grounded, and the source is connected to the SCALER chip.

[0014] Further, the CC detection circuit includes a MOS tube Q16, a resistor R201, a resistor R204, a MOS tube Q22, a MOS tube Q23, a resistor R202, a resistor R203, a MOS tube Q14, a resistor R205, a resistor R198, a resistor R199, a resistor R200, and a MOS tube Q17; the third pin of the MOS tube Q16 is connected to a +3V3 voltage, the second pin of the MOS tube Q16 is connected to the resistor R201 and the resistor R204 in sequence and then connected to the third pin of the MOS tube Q22, the first pin of the MOS tube Q16 is connected to the first pin of the MOS tube Q23, the second pin of the MOS tube Q22 is grounded, and the common connection point of the resistor R201 and the resistor R204 is connected to the CC1 end of the CC mis-discharge circuit; the third pin of the MOS tube Q23 is connected to a +3V3 voltage, and the second pin of the MOS tube Q23 is connected to the resistor R202 in sequence The resistor R203 is connected to the third pin of the MOS tube Q14, the common connection point of the resistor R201 and the resistor R204 is connected to the CC2 end of the CC mis-discharge circuit, the first pin of the MOS tube Q23 is connected to the third pin of the MOS tube Q17, the second pin of the MOS tube Q14 is grounded, the first pin of the MOS tube Q14 is connected to the resistor R205 and then connected to the SCALER chip pin, one end of the resistor R198 is connected to the +3V3 voltage, and the other end is connected to the first pin of the MOS tube Q14; one end of the resistor R199 is connected to the +12V voltage, and the other end is connected to the first pin of the MOS tube Q23, the first pin of the MOS tube Q23 is connected to the resistor R200 and then grounded, the second pin of the MOS tube Q17 is grounded, and the first pins of the three MOS tubes, the first pin of the MOS tube Q17, the first pin of the MOS tube Q22 and the first pin of the MOS tube Q14, are connected together.

[0015] Further, the CC mis-discharge circuit includes a resistor R34, a resistor R35, a MOS tube Q11 and a MOS tube Q18; the drain of the MOS tube Q11 is connected to the CC1 pin of the TYPE C interface, the gate of the MOS tube Q11 is connected to the resistor R35 and then grounded, the gate of the MOS tube Q11 is connected to one end of the resistor R34, the other end of the resistor R34 is connected to a +5V voltage, and the source of the MOS tube Q11 is connected to the CC1 end of the CC detection circuit; the drain of the MOS tube Q18 is connected to the CC2 pin of the TYPE C interface, the gate of the MOS tube Q18 is connected to the gate of the MOS tube Q11, and the gate source of the MOS tube Q18 is connected to the CC2 end of the CC detection circuit.

[0016] Furthermore, the CC pin of the TYPE C interface is connected to the CC mis-discharge circuit through a TVS diode.

[0017] Furthermore, the SUB pin of the TYPE C interface is connected to the SUB / AUX switching circuit through a TVS diode.

[0018] Compared with the prior art, the advantages and positive effects of the present invention are: the circuit of the present invention is simple in periphery and low in cost, and the TYPE C circuit without a PD chip completes communication through the CC detection circuit. The high and low levels in the CC detection circuit complete the detection communication, and only a few MOS tubes are needed to solve the CC communication problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a circuit block diagram of the present invention;

[0020] Figure 2 This is a pin connection diagram of a TYPE C interface of the present invention;

[0021] Figure 3 This is the connection diagram of SUB / AUX conversion circuit;

[0022] Figure 4 This is the external charging circuit diagram;

[0023] Figure 5 This is the TYPE C VBUS detection circuit diagram;

[0024] Figure 6 This is the CC detection circuit diagram;

[0025] Figure 7 This is the CC mis-discharge circuit diagram;

[0026] Figure 8 This is the pin connection diagram of the SCALER chip;

[0027] Fig. 9 This is the connection diagram of the upper pin part of the SCALER chip;

[0028] Fig.10 This is the connection diagram of the left pin section of the SCALER chip;

[0029] Fig.11 This is the connection diagram of the lower pin part of the SCALER chip;

[0030] Fig.12 This is the connection diagram of the right pin part of the SCALER chip; DETAILED DESCRIPTION

[0031] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0032] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] A TYPE C circuit without a PD chip of the present invention, such as Figure 1-7 As shown, a TYPE C circuit without a PD chip includes: a TYPE C interface; an external charging circuit, whose voltage output end is connected to the VBUS end of the TYPE C interface for power supply; a TYPE C VBUS detection circuit, whose input end is connected to the VBUS end of the TYPE C interface for VBUS detection and control; a SUB / AUX switching circuit, whose input end is connected to the SUB pin of the TYPE C interface, for converting the DP signal to the AUX signal when the TYPE C is inserted forward or reversely; a CC mis-discharge circuit, whose input end is connected to the CC pin of the TYPE C interface for discharge protection; a CC detection circuit, whose input end is connected to the CC mis-discharge circuit output end, for TYPE C CC terminal signal state detection; a SCALER chip, whose DP end is connected to the TX / RX port of the TYPE C interface, the CC detection circuit output end is connected to the ADC end of the SCALER chip, and the SUB / AUX switching circuit output end is connected to the SCALER chip input end, for signal transmission control. The CC detection circuit is used to replace the PD chip to communicate with the SCALER chip, and the CC detection circuit communicates with the SCALER chip through the high and low levels of the CC1 and CC2 pins.

[0034] Furthermore, the TYPE C VBUS detection circuit includes resistor R206, resistor R207, resistor R208, capacitor C154 and MOS tube Q24; one end of resistor R206 is connected to the VBUS end of the TYPE C interface, and the other end is connected to resistor R207 and then grounded; the drain of MOS tube Q24 is connected to +3V3, the gate is connected to the common connection point of resistor R206 and resistor R207, the source is connected to capacitor C154 and then grounded, the source is connected to resistor R208 and then grounded, and the source is connected to the SCALER chip (VBUS_DET end, pin 49 of the SCALER chip). The TYPE C VBUS detection circuit can detect current and detect the voltage value on the CC pin to obtain the current output capability. VBUS_DET is connected to the main chip to detect whether a TYPE C device is connected. When TYPE C is not connected, TYPE_C_VBUS is not powered, Q24 is not conducting, VBUS_DET is connected to ground through R208, so the chip IO pin reads a low voltage. When a TYPE C device is connected, TYPE_C_VBUS is powered, Q24 is conducting, and VBUS_DET is equivalent to being connected to +3V3, so the SCALER chip IO pin reads a high voltage. The VBUS_DET terminal (pin 49) of the SCALER chip is connected to the VBUS_DET terminal of the TYPE C VBUS detection circuit.

[0035] Furthermore, if Figure 6As shown, the CC detection circuit includes a MOS tube Q16, a resistor R201, a resistor R204, a MOS tube Q22, a MOS tube Q23, a resistor R202, a resistor R203, a MOS tube Q14, a resistor R205, a resistor R198, a resistor R199, a resistor R200, and a MOS tube Q17; the third pin of the MOS tube Q16 is connected to a +3V3 voltage, the second pin of the MOS tube Q16 is connected to the resistor R201 and the resistor R204 in sequence and then connected to the third pin of the MOS tube Q22, the first pin of the MOS tube Q16 is connected to the first pin of the MOS tube Q23, the second pin of the MOS tube Q22 is grounded, and the common connection point of the resistor R201 and the resistor R204 is connected to the CC1 end of CC mis-discharge; the third pin of the MOS tube Q23 is connected to a +3V3 voltage, the second pin of the MOS tube Q23 is connected to the resistor R202 and The resistor R203 is connected to the third pin of the MOS tube Q14, the common connection point of the resistor R201 and the resistor R204 is connected to the CC2 end of the CC mis-discharge, the first pin of the MOS tube Q23 is connected to the third pin of the MOS tube Q17, the second pin of the MOS tube Q14 is grounded, the first pin of the MOS tube Q14 is connected to the resistor R205 and then connected to the SCALER chip pin, one end of the resistor R198 is connected to the +3V3 voltage, and the other end is connected to the first pin of the MOS tube Q14; one end of the resistor R199 is connected to the +12V voltage, and the other end is connected to the first pin of the MOS tube Q23, the first pin of the MOS tube Q23 is connected to the resistor R200 and then grounded, the second pin of the MOS tube Q17 is grounded, and the first pins of the three MOS tubes, the first pin of the MOS tube Q17, the first pin of the MOS tube Q22 and the first pin of the MOS tube Q14, are connected together. MOS tubes Q16, Q23, Q17, Q22, Q14, and other PD chips mainly communicate the protocol through CC, and CC requires IO with ADC function. The main chip has IO with this function, so it can replace the function of PD chip. Figure 6 As shown, DFP is only connected to pin 1 of Q16 and Q23, PR_SWAP is only connected to pin 1 of Q17, Q22, and Q14, and UD_SWAP is connected to pin 24 of the SCALER main chip. Fig.10As shown. Because TYPE C devices are divided into power supply devices, charging devices and dual devices, this circuit is used to determine the identity of TYPE C devices. When a TYPE C device is connected, whether it is plugged in forward or reverse, the CC end will communicate the protocol with the main chip. After communicating the protocol, the SCALER main chip will tell the TYPE C device whether I want to charge or power supply. When UD_SWAP gives a high potential, PR_SWAP is also high, Q17 is turned on, DFP is low, Q16, Q23 are not turned on, CC1 and CC2 will be low, when UD_SWAP gives a low potential, PR_SWAP is also low, Q17 is not turned on, DFP is high through R199, R200 voltage divider, Q16, Q23 are turned on, CC1 and CC2 will be high, and the high and low signals are set by UD_SWAP to tell the TYPE C device what its identity is. The output end of the CC detection circuit is connected to the ADC end of the SCALER chip, as shown in Figure 6 and Fig. 9 , the ADC4 terminal (pin 162) and ADC3 terminal (pin 159) of the SCALER chip are connected to the CC2 terminal and CC1 terminal respectively.

[0036] Furthermore, if Figure 7 As shown, the CC mis-discharge circuit includes resistor R34, resistor R35, MOS tube Q11 and MOS tube Q18; the drain (third pin) of MOS tube Q11 is connected to the CC1 pin of TYPE C interface as shown in FIG. Figure 2 and Figure 7 As shown, the third pin of MOS tube Q11 is connected to the CC1 pin (the 5th pin, CC1_A5) of the TYPE C interface; the gate (first pin) of MOS tube Q11 is connected to the resistor R35 and then grounded, the gate (first pin) of MOS tube Q11 is connected to one end of the resistor R34, the other end of the resistor R34 is connected to the +5V voltage, and the MOS tube Q11 (second pin) is connected to the CC1 end of the CC detection circuit, as shown in FIG. Figure 6 and Figure 7 The CC1 terminal of the MOS tube Q18 (the third pin) is connected to the CC2 pin of the TYPE C interface, such as Figure 2 and Figure 7 As shown, the third pin of MOS tube Q18 is connected to the CC2 pin (the 17th pin, CC2_B5) of TYPE C interface; the gate (first pin) of MOS tube Q18 is connected to the gate (first pin) of MOS tube Q11, and the gate source (second pin) of MOS tube Q18 is connected to the CC2 end of CC detection circuit, as shown in FIG. Figure 6 and Figure 7 The CC mis-discharge circuit can be used for discharge protection to provide circuit safety.

[0037] Furthermore, the CC pin of the TYPE C interface is connected to the CC mis-discharge circuit through a TVS diode. The ESD protection chip is used to protect USB signals and prevent static electricity.

[0038] Furthermore, the SUB pin of the TYPE C interface is connected to the SUB / AUX switching circuit through a TVS diode. The ESD protection chip is used to protect USB signals and prevent static electricity.

[0039] The invention has a simple circuit periphery and low cost. The TYPE C circuit without a PD chip completes communication through the CC detection circuit. The high and low levels in the CC detection circuit complete the detection communication. Only a few MOS tubes are needed to solve the CC communication problem. The few MOS are Q16, Q23, Q17, Q22, and Q14 as mentioned above. Other PD chips mainly communicate the protocol through CC, and CC requires IO with ADC function. The main chip has IO with this function to complete the communication.

[0040] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, and the working principle of the present invention has been explained, but the present invention is not limited thereto. Various changes made within the knowledge scope of technicians in the relevant technical field without departing from the purpose of the present invention are all within the protection scope of the present invention.

Claims

1. A TYPE C circuit without a PD chip, characterized in that: include: TYPE C interface, used to connect to USB TYPE C devices; The voltage output end of the external charging circuit is connected to the VBUS end of the TYPE C interface for power supply; TYPE C VBUS detection circuit, whose input end is connected to the VBUS end of the TYPE C interface, is used for VBUS detection and control; The SUB / AUX switching circuit has an input end connected to the SUB pin of the TYPE C interface and is used to convert the DP signal into the AUX signal when the TYPE C is inserted forward or reversely; The CC mis-discharge circuit has an input end connected to the CC pin of the TYPE C interface for discharge protection; A CC detection circuit, whose input end is connected to the output end of the CC mis-discharge circuit, is used for detecting the signal state of the CC pin of TYPE C; The SCALER chip has a DP end connected to the TX / RX port of the TYPE C interface, a CC detection circuit output end connected to the ADC end of the SCALER chip, and a SUB / AUX switching circuit output end connected to the SCALER chip input end, which is used for signal transmission control; The CC detection circuit includes a MOS tube Q16, a resistor R201, a resistor R204, a MOS tube Q22, a MOS tube Q23, a resistor R202, a resistor R203, a MOS tube Q14, a resistor R205, a resistor R198, a resistor R199, a resistor R200, and a MOS tube Q17; the third pin of the MOS tube Q16 is connected to a +3V3 voltage, the second pin of the MOS tube Q16 is connected to the resistor R201 and the resistor R204 in sequence and then connected to the third pin of the MOS tube Q22, the first pin of the MOS tube Q16 is connected to the first pin of the MOS tube Q23, the second pin of the MOS tube Q22 is grounded, and the common connection point of the resistor R201 and the resistor R204 is connected to the CC1 end of the CC mis-discharge circuit; the third pin of the MOS tube Q23 is connected to a +3V3 voltage, the second pin of the MOS tube Q23 is connected to the resistor R202 and the resistor R204 in sequence The resistor R203 is connected to the third pin of the MOS tube Q14, the common connection point of the resistor R201 and the resistor R204 is connected to the CC2 end of the CC mis-discharge circuit, the first pin of the MOS tube Q23 is connected to the third pin of the MOS tube Q17, the second pin of the MOS tube Q14 is grounded, the first pin of the MOS tube Q14 is connected to the resistor R205 and then connected to the pin of the SCALER chip, one end of the resistor R198 is connected to the +3V3 voltage, and the other end is connected to the first pin of the MOS tube Q14; one end of the resistor R199 is connected to the +12V voltage, and the other end is connected to the first pin of the MOS tube Q23, the first pin of the MOS tube Q23 is connected to the resistor R200 and then grounded, the second pin of the MOS tube Q17 is grounded, and the first pins of the three MOS tubes, the first pin of the MOS tube Q17, the first pin of the MOS tube Q22 and the first pin of the MOS tube Q14, are connected together.

2. The TYPE C circuit without a PD chip according to claim 1, characterized in that: The TYPE C VBUS detection circuit includes a resistor R206, a resistor R207, a resistor R208, a capacitor C154 and a MOS tube Q24; one end of the resistor R206 is connected to the VBUS end of the TYPE C interface, and the other end is connected to the resistor R207 and then grounded; the drain of the MOS tube Q24 is connected to the +3V3 voltage, the gate is connected to the common connection point of the resistor R206 and the resistor R207, the source is connected to the capacitor C154 and then grounded, the source is connected to the resistor R208 and then grounded, and the source is connected to the SCALER chip.

3. The TYPE C circuit without a PD chip according to claim 1, characterized in that: The CC mis-discharge circuit includes a resistor R34, a resistor R35, a MOS tube Q11 and a MOS tube Q18; the drain of the MOS tube Q11 is connected to the CC1 pin of the TYPE C interface, the gate of the MOS tube Q11 is connected to the resistor R35 and then to ground, the gate of the MOS tube Q11 is connected to one end of the resistor R34, the other end of the resistor R34 is connected to a +5V voltage, and the source of the MOS tube Q11 is connected to the CC1 end of the CC detection circuit; the drain of the MOS tube Q18 is connected to the CC2 pin of the TYPE C interface, the gate of the MOS tube Q18 is connected to the gate of the MOS tube Q11, and the gate source of the MOS tube Q18 is connected to the CC2 end of the CC detection circuit.

4. The TYPE C circuit without a PD chip according to claim 3, characterized in that: The CC pin of the TYPE C interface is connected to the CC mis-discharge circuit through a TVS diode.

5. The TYPE C circuit without a PD chip according to claim 3, characterized in that: The SUB pin of the TYPE C interface is connected to the SUB / AUX switching circuit through a TVS diode.

Images