CH340G
USB-to-UART converter requiring external 12MHz crystal, pin-compatible with CH340C for legacy designs
Product Overview
Description
CH340G is a USB-to-UART converter similar to CH340C but requires an external 12MHz crystal oscillator.
This variant is pin-compatible with CH340C and can be used in legacy designs or applications requiring external clock synchronization.
The chip supports baud rates up to 2Mbps and both 5V/3.3V IO levels with comprehensive driver support.
Product Series
CH
Primary Application
Legacy system upgrades
Key Features
- USB 2.0 Full Speed compliant
- Requires external 12MHz crystal
- Supports 5V and 3.3V IO voltage
- Baud rates from 50bps to 2Mbps
- Hardware flow control support
- Modem handshake signals
- 5V tolerant inputs
- Pin-compatible with CH340C
Specifications
| Interface | USB 2.0 Full Speed to UART |
|---|---|
| Baud Rate | 50bps to 2Mbps |
| IO Voltage | 5V or 3.3V (selectable) |
| USB Speed | Full Speed (12Mbps) |
| Handshake | RTS, CTS, DTR, DSR, DCD, RI |
| Clock Source | External 12MHz crystal required |
| Temperature Range | -40°C to +85°C |
| Package | SOP-16, DIP-16 |
Applications
Legacy system upgrades
Electronic system design
External clock synchronization
Electronic system design
USB-to-serial adapters
Electronic system design
Microcontroller programming
Industrial automation and control
Industrial control systems
Industrial automation and control
FAE Expert Insights
"CH340G is the predecessor to CH340C and requires an external crystal. I recommend CH340C for all new designs, but CH340G is useful for maintaining compatibility with existing PCB layouts or when external clock synchronization is required. The performance and features are identical to CH340C - only the clock source differs. If you're designing a new product, use CH340C to save the crystal cost and PCB space."
Legacy-compatible variant for existing designs
— David Liu, BeiLuo