USB Type-C 3.1

Overview

USB Type-C 3.1 Female Connector (SMD/Through-hole) — a 24-pin reversible USB-C receptacle connector supporting USB 3.1 Gen 1/Gen 2 data transfer speeds, USB Power Delivery (PD), and DisplayPort Alternate Mode. Features the modern reversible plug design — no wrong way to insert. Used in custom PCB designs, development boards, charging circuits, data interfaces, and electronic product manufacturing. Fully compliant with USB Type-C specification.

Specifications

Parameter	Value
Connector Type	USB Type-C Female Receptacle
USB Standard	USB 3.1 Gen 1 / Gen 2
Total Pins	24 (12 top + 12 bottom)
Data Rate	Up to 10Gbps (USB 3.1 Gen 2)
Power Delivery	Up to 100W (USB PD 3.0)
Voltage Rating	Up to 20V
Current Rating	Up to 5A
Contact Resistance	≤30mΩ
Insulation Resistance	≥100MΩ
Dielectric Strength	500VAC
Mating Cycles	≥10,000
Operating Temperature	-40°C to +85°C
Mounting	SMD / Through-hole
Material	Stainless steel shell + LCP body
Finish	Nickel plated contacts

Pin Configuration

Top Row (A Side)

Pin	Name	Description
A1	GND	Ground
A2	TX1+	SuperSpeed TX differential pair +
A3	TX1-	SuperSpeed TX differential pair -
A4	VBUS	Power (5V/20V)
A5	CC1	Configuration Channel 1
A6	D+	USB 2.0 data +
A7	D-	USB 2.0 data -
A8	SBU1	Sideband Use 1 (Alt Mode)
A9	VBUS	Power (5V/20V)
A10	RX2-	SuperSpeed RX differential pair -
A11	RX2+	SuperSpeed RX differential pair +
A12	GND	Ground

Bottom Row (B Side)

Pin	Name	Description
B1	GND	Ground
B2	TX2+	SuperSpeed TX differential pair +
B3	TX2-	SuperSpeed TX differential pair -
B4	VBUS	Power (5V/20V)
B5	CC2	Configuration Channel 2
B6	D+	USB 2.0 data + (mirrored)
B7	D-	USB 2.0 data - (mirrored)
B8	SBU2	Sideband Use 2 (Alt Mode)
B9	VBUS	Power (5V/20V)
B10	RX1-	SuperSpeed RX differential pair -
B11	RX1+	SuperSpeed RX differential pair +
B12	GND	Ground

Features

• Reversible design — works both ways, no wrong orientation
• USB 3.1 Gen 2 — up to 10Gbps SuperSpeed+ data transfer
• USB Power Delivery — up to 100W (20V × 5A) charging
• Backward compatible — USB 2.0 and USB 3.0 devices work
• CC pins — cable orientation detection and power negotiation
• DisplayPort Alt Mode — video output via USB-C (with DP Alt Mode)
• Thunderbolt 3/4 compatible connector (protocol dependent)
• Stainless steel shell — durable and shielded
• SMD mounting — suitable for reflow soldering
• High mating cycles — ≥10,000 insertions

USB-C vs Previous USB Connectors

Feature	USB-C	Micro-USB	Mini-USB	USB-A
Reversible	✅ Yes	❌ No	❌ No	❌ No
Max Data	10Gbps	480Mbps	480Mbps	10Gbps
Max Power	100W	10W	10W	15W
Video Out	✅ Yes	❌ No	❌ No	❌ No
Pins	24	5	5	4
Size	Small	Very Small	Small	Large

Basic USB 2.0 Only Wiring (Simplified)

For simple USB 2.0 charging + data applications:

USB-C Pin	Connection
A1, B1, A12, B12	GND
A4, A9, B4, B9	VBUS (5V)
A6, B6	D+ (connect together)
A7, B7	D- (connect together)
A5 (CC1)	5.1kΩ to GND
B5 (CC2)	5.1kΩ to GND

⚠️ CC resistors are MANDATORY — without 5.1kΩ pull-down on CC1 and CC2, USB-C chargers will not provide power!

USB Power Delivery Circuit

For charging-only applications (5V/2A):

• VBUS: (A4,A9,B4,B9) ──── 5V Output
• GND: (A1,B1,A12,B12) ── GND
• CC1: (A5) ──── 5.1kΩ ── GND
• CC2: (B5) ──── 5.1kΩ ── GND
• D+: (A6,B6) ─ NC (or connect for data)
• D-: (A7,B7) ─ NC (or connect for data)

Soldering Guide

SMD Reflow

1. Apply solder paste to PCB pads
2. Place connector carefully — align shell mounting holes
3. Reflow at 245°C peak temperature
4. Check continuity after soldering
5. Clean flux residue with IPA

Hand Soldering

1. Solder shell/mounting tabs first for mechanical stability
2. Use fine tip iron at 320°C
3. Solder signal pins with thin solder (0.5mm)
4. Check under magnification for bridges
5. Test with multimeter for shorts

PCB Footprint Guidelines

• Pad pitch: 0.5mm (signal pins)
• Shell mounting: 2× large pads for mechanical strength
• Ground pour: surround connector with GND copper pour
• Decoupling: 100nF capacitor on VBUS near connector
• EMI: keep high-speed TX/RX traces short and matched length

USB 3.1 Speed Modes

Mode	Speed	Name
USB 2.0	480 Mbps	Hi-Speed
USB 3.0 / 3.1 Gen 1	5 Gbps	SuperSpeed
USB 3.1 Gen 2	10 Gbps	SuperSpeed+
USB 3.2 Gen 2×2	20 Gbps	SuperSpeed+ 2-lane

⚠️ Important Notes

• CC resistors mandatory — 5.1kΩ pull-down on both CC1 and CC2 for UFP (device)
• Do NOT short CC pins — used for power negotiation and orientation detection
• Match differential pairs — TX+/TX- and RX+/RX- must be equal length traces
• Impedance control — SuperSpeed pairs require 90Ω differential impedance
• Shield grounding — connect shell to GND with 0Ω resistor or direct connection
• VBUS protection — add TVS diode on VBUS for ESD protection
• Current rating — use adequate copper weight for high-current power delivery

Applications

• Custom development board USB port
• USB charging circuit design
• PCB power input connector
• Data acquisition devices
• USB audio interfaces
• Custom IoT device USB interface
• Arduino / ESP32 custom board design
• USB HID device development
• Power bank design
• Industrial USB interface
• Wearable electronics charging port