Content Menu
● Introduction
● Understanding USB-C Cable Basics
>> USB-C Cable Features
>> Key USB-C Pins for Power
● Step-by-Step Guide to Wiring a USB-C Cable for Power
>> 1. Identify the Cable Type and Purpose
>> 2. Open the USB-C Cable and Locate Wires
>> 3. Understand the Role of the CC Pins
>> 4. Wiring the Power Lines
>> 5. Configure the CC Pins for Power Delivery
>> 6. Test the Cable
● Important Safety and Practical Considerations
● Visual Aids and Videos
>> Diagrams
>> Recommended Videos
● Conclusion
● Frequently Asked Questions (FAQs)
>> 1. How do I identify the power wires inside a USB-C cable?
>> 2. Can I hardwire a USB-C cable directly to a 12V power source?
>> 3. What is the function of the CC pins in USB-C cables?
>> 4. How can I enable fast charging with a USB-C cable?
>> 5. Are all USB-C cables capable of delivering the same power?
● Citations:
Introduction
USB-C has become the universal standard for charging and data transfer, offering versatility, reversibility, and the ability to deliver high power levels. Wiring a USB-C cable for power, especially for DIY projects or custom installations, requires understanding the cable's pinout, power delivery protocols, and safety considerations. This article will guide you through the process of wiring a USB-C cable for power, complete with detailed explanations, diagrams, and references to helpful videos.
Understanding USB-C Cable Basics
USB-C Cable Features
- Reversible Connector: The USB-C plug can be inserted either way, thanks to its symmetrical design.
- Power Delivery (PD): USB-C supports up to 240W of power with voltage up to 48V and current up to 5A, negotiated dynamically between devices.
- Data Transfer: Supports USB 2.0, 3.0, and 3.1 standards with high-speed data lines.
- Communication Channels: Special pins for configuration and power negotiation.
Key USB-C Pins for Power
| Pin Name | Pin Number(s) | Function |
| VBUS | A1, B1 | Power supply (default 5V) |
| GND | A4, B4, A9, B9 | Ground |
| CC (Configuration Channel) | A5, B5 | Communication for power negotiation |
| D+ / D- | A6, A7, B6, B7 | Data lines (USB 2.0) |
The VBUS pins carry the power voltage, typically 5V by default, but can be negotiated up to 20V or more with USB Power Delivery protocols. The CC pins are critical for establishing the power role (source or sink) and negotiating current and voltage levels[2][4].
Step-by-Step Guide to Wiring a USB-C Cable for Power
1. Identify the Cable Type and Purpose
- Determine if the cable is for simple 5V power or for USB Power Delivery (higher voltages).
- Decide if the cable will be used as a power source or a power sink (device receiving power).
2. Open the USB-C Cable and Locate Wires
Typical USB-C cables contain:
- Red wires: VBUS (power)
- Black wires: Ground (GND)
- White and Green wires: Data lines (D- and D+)
- Other wires: CC lines and possibly SBU (sideband use) lines
Note: Some cables have multiple red wires for power, but these may not carry voltage until the CC pins are correctly configured[2][5].
3. Understand the Role of the CC Pins
- The CC pins determine whether the cable will supply or consume power.
- A pull-up resistor (Rp) on the source side pulls the CC line high.
- A pull-down resistor (Rd) on the sink side pulls the CC line low.
- This resistor configuration signals the devices to negotiate power levels and roles[6].
4. Wiring the Power Lines
- Connect the VBUS (red wire) to the positive terminal of your power supply.
- Connect the GND (black wire) to the negative terminal or ground.
- Ensure the power supply voltage matches the device requirements (usually 5V for basic USB power).
5. Configure the CC Pins for Power Delivery
- To enable power delivery, connect a 5.1 kΩ pull-down resistor between the CC pin and ground on the sink side.
- On the source side, use a pull-up resistor to set the current capability (e.g., 56 kΩ for default USB power, lower for higher current).
- This resistor setup allows the devices to negotiate power levels safely[6][7].
6. Test the Cable
- Use a multimeter to verify voltage on the VBUS line.
- Confirm the CC pins voltage levels correspond to the expected power role.
- Test with the device to ensure it powers up correctly.
Important Safety and Practical Considerations
- Do not directly connect a 12V source to a USB-C cable: USB-C power is typically 5V unless negotiated via USB PD.
- Use a DC-DC converter or USB PD controller: To safely step down or negotiate higher voltages.
- Avoid cheap or uncertified cables: Poor quality cables may damage devices or fail to deliver power correctly.
- Fuse protection: When hardwiring in vehicles or other systems, use a fuse to protect against short circuits[1].
Visual Aids and Videos
Diagrams
- USB-C Cable Wiring Diagram: Shows pin numbers, wire colors, and functions for USB 2.0 power wiring[2].
| USB A Pin | USB C Pin(s) | Wire Color | Description |
| 1 | A4, B4, A9, B9 | Red | +5V (VBUS) |
| 4 | A1, B1, A12, B12 | Black | Ground (GND) |
| 2 | A7 | White | Data- (D-) |
| 3 | A6 | Green | Data+ (D+) |
- USB-C Pinout Overview: Shows the role of CC, VBUS, GND, and data pins[4].
Recommended Videos
- USB-C Power Delivery Hardware Design by Phil's Lab: Explains USB PD basics and hardware design for USB-C power delivery systems[3].
- Power Anything with USB-C Instead! (USB PD DIY) by Zibartas: Demonstrates how to use USB-C PD trigger boards for DIY projects, enabling devices to use USB-C chargers at various voltages[8].
Conclusion
Wiring a USB-C cable for power involves more than just connecting red and black wires. Understanding the USB-C pinout, especially the critical role of the CC pins for power negotiation, is essential for safe and effective power delivery. Whether you are creating a simple 5V power cable or implementing USB Power Delivery for higher voltages, following the correct wiring and resistor configurations ensures device compatibility and safety. Utilizing diagrams, proper tools, and resources like USB PD trigger boards can simplify the process and enable versatile USB-C power applications.
Frequently Asked Questions (FAQs)
1. How do I identify the power wires inside a USB-C cable?
Power wires are typically red for VBUS (+5V) and black for ground. Data wires are usually white and green. However, some USB-C cables have multiple red wires or additional wires for CC and SBU functions[2][5].
2. Can I hardwire a USB-C cable directly to a 12V power source?
No. USB-C devices expect 5V by default, and higher voltages require negotiation via USB Power Delivery protocols. You must use a DC-DC converter or a USB PD controller to safely convert 12V to the appropriate USB-C voltage[1].
3. What is the function of the CC pins in USB-C cables?
The CC (Configuration Channel) pins manage power role detection and power negotiation between devices. They use pull-up and pull-down resistors to signal whether the device is a power source or sink and the current capability[4][6].
4. How can I enable fast charging with a USB-C cable?
Fast charging requires proper USB Power Delivery negotiation via the CC pins and a compatible charger and device. The cable must support the required current (up to 5A) and voltage (up to 20V or more)[6].
5. Are all USB-C cables capable of delivering the same power?
No. USB-C cables vary in quality and specifications. Some support only USB 2.0 speeds and 3A current, while others support USB 3.1 and 5A current for up to 100W or more. Always use certified cables for high power delivery[2][6].
Citations:
[1] https://www.reddit.com/r/AutoDIY/comments/16286ju/how_can_i_hardwire_a_usbc_cable/
[2] https://electrosemic.com/usb-c-cable-wiring-diagram-and-schematics/
[3] https://www.youtube.com/watch?v=W13HNsoHj7A
[4] https://wandkey.com/usb-c-pinout-guide-and-features/
[5] https://electronics.stackexchange.com/questions/310488/usb-c-cable-layout
[6] https://www.pshinecable.com/article/usb-c-power-delivery--what-makes-a-usb-c-cable-fast-charging.html
[7] https://hackaday.com/2023/08/07/all-about-usb-c-example-circuits/
[8] https://www.youtube.com/watch?v=ZHnSpJe-dMk
[9] https://www.anker.com/blogs/cables/how-to-wire-a-usb-cable-for-power
[10] https://www.pshinecable.com/article/usb-c-cable-wiring-diagram.html
[11] https://www.pinterest.com/pin/814940495061901957/
[12] https://www.youtube.com/watch?v=qV03FfdPHOw
[13] https://www.pinterest.com/pin/26740191531279130/
[14] https://knowledge.cambrionix.com/Content/Articles/USB/USB-Type-C-Pinout.htm?TocPath=Articles%7CUSB%7C_____12
[15] https://www.youtube.com/watch?v=LySrwTSr2qg
[16] https://electrosemic.com/usb-c-cable-color-code/
[17] https://www.youtube.com/watch?v=yyUydcPD7cQ
[18] https://www.istockphoto.com/photos/usb-type-c-cable
[19] https://www.allelcoelec.com/blog/usb-c-pinout-and-features.html
[20] https://anothersupersite.com/diy-usb-cables-and-how-usb-type-c-is-wired/
