Micro-USB (Type-B) Connector Pinout
The 5-pin Micro-USB Type-B connector — power, USB 2.0 data, and OTG ID.
Overview
Micro-USB Type-B is the small 5-pin connector found on countless older phones, modules, and dev boards. It carries 5V power, the USB 2.0 differential data pair, and an ID pin used for USB On-The-Go (OTG).
For a normal device you only need VBUS, D−, D+, and GND. The ID pin selects OTG role: left floating the device acts as a peripheral; tied to GND it becomes an OTG host.
Pinout
| Pin | Name | Function | Description |
|---|---|---|---|
| 1 | VBUS | POWER | +5V bus power. |
| 2 | D− | USB2 / DATA | USB 2.0 data −. |
| 3 | D+ | USB2 / DATA | USB 2.0 data +. |
| 4 | ID | CC | OTG role select: floating = device, GND = host. |
| 5 | GND | GND | Ground. |
Notes
- Most cables/boards leave ID unconnected (device mode).
- Rated ~1.8 A max; not designed for high-power delivery like USB-C PD.
Reference: USB 2.0 Micro-USB spec· verified 2026-06-21