WCH (Nanjing Qinheng) Manufacturer Skill

MPN Structure

WCH has two main product categories with different structures:

RISC-V and ARM MCUs (CH32 Series)

CH32[CORE][SERIES][PIN][FLASH][PKG][TEMP]
│     │      │     │     │     │     │
│     │      │     │     │     │     └── Temperature (6=industrial)
│     │      │     │     │     └── Package type (T=LQFP, U=QFN)
│     │      │     │     └── Flash size (4=16KB, 8=64KB, B=128KB, C=256KB)
│     │      │     └── Pin code (C=48, R=64, V=100)
│     │      └── Series (003=entry, 103=standard, 203=enhanced, 30x=high-perf)
│     └── Core (V=RISC-V, F=ARM Cortex-M3)
└── CH32 prefix

USB Interface Chips (CH34x Series)

CH[SERIES][VARIANT]
│    │       │
│    │       └── Package variant (G=SOP-16, C=SOP-16 w/crystal, K=ESSOP-10)
│    └── Series (340=USB-UART, 341=USB-Multi, 9340=Enhanced)
└── CH prefix

Example Decoding

CH32V103C8T6
│   │  │ │││
│   │  │ ││└── Temp 6 (industrial)
│   │  │ │└── Package T (LQFP)
│   │  │ └── Flash 8 (64KB)
│   │  └── Pin C (48-pin)
│   └── Series 103 (QingKe V3A core)
└── Core V (RISC-V)

CH340G
│  │ │
│  │ └── Package G (SOP-16)
│  └── Series 340 (USB to UART)
└── CH prefix

---

Package Codes

MCU Pin Codes

Code	Package	Pin Count
A	QFN-28	28
C	LQFP-48	48
F	TSSOP-20	20
G	QFN-20	20
J	SOP-20	20
K	ESSOP-20	20
N	SOP-8	8
R	LQFP-64	64
U	QFN-20	20
V	LQFP-100	100
W	QFN-28	28

USB Interface Chip Packages

Suffix	Package
G	SOP-16
C	SOP-16 (integrated crystal)
K	ESSOP-10
N	SOP-8
E	MSOP-10
X	ESSOP-10
T	SSOP-20
A	SOP-28
B	SSOP-28
S	SOP-28
H	SOP-28
L	LQFP-48

---

Product Families

RISC-V MCUs (CH32Vxxx)

Series	Core	Clock	Features
CH32V003	QingKe V2A	48MHz	Entry-level, 2KB SRAM
CH32V103	QingKe V3A	80MHz	Standard, 20KB SRAM
CH32V203	QingKe V4B	144MHz	Enhanced, 64KB SRAM
CH32V208	QingKe V4C	144MHz	Bluetooth LE support
CH32V303	QingKe V4F	144MHz	High-performance
CH32V305	QingKe V4F	144MHz	USB HS, Ethernet
CH32V307	QingKe V4F	144MHz	USB HS, Ethernet, CAN

ARM Cortex-M3 MCUs (CH32Fxxx)

Series	Core	Clock	Features
CH32F103	Cortex-M3	72MHz	STM32F103 compatible
CH32F203	Cortex-M3	144MHz	Enhanced peripherals

USB Interface Chips

Series	Type	Features
CH340	USB-UART	Most popular, no crystal needed (CH340C)
CH341	USB-Multi	UART/I2C/SPI/Parallel
CH9340	USB-UART	Enhanced CH340
CH342-CH348	USB-UART	Various channel counts

Other Interface Chips

Series	Type	Features
CH395	Ethernet	10/100M Ethernet controller
CH9121	ETH-UART	Ethernet to serial
CH9141	BLE-UART	Bluetooth LE module
CH9143	BLE-UART	Bluetooth LE module
CH334	USB Hub	USB hub controller
CH224	USB PD	Power Delivery controller
CH552/554/559	8051 USB	8051-based USB MCUs

---

Flash Size Encoding

Code	Flash Size
4	16KB
6	32KB
8	64KB
B	128KB
C	256KB
D	384KB
E	512KB
G	1024KB

---

Handler Implementation Notes

MCU Package Code Extraction

// MCU format: CH32V103C8T6
// Position:   01234567890123
//                    ^-- position 8 is pin code 'C'
char pinCode = mpn.charAt(8);
String packageType = MCU_PACKAGE_CODES.get(pinCode);

// Pin count also at position 8
Integer pinCount = MCU_PIN_COUNTS.get(pinCode);

USB Interface Package Extraction

// CH340G -> G = SOP-16
// Last character is package code
String suffix = mpn.substring(mpn.length() - 1);
String pkg = USB_PACKAGE_CODES.get(suffix);

// CH340 without suffix defaults to SOP-16
if (mpn.matches("^CH(340|341|9340)$")) {
    return "SOP-16";  // Default package
}

Core Type Detection

The handler provides

getCoreType()

for MCUs:

Series	Core Type
CH32V003	RISC-V QingKe V2A
CH32V103	RISC-V QingKe V3A
CH32V203/208	RISC-V QingKe V4B
CH32V303/305/307	RISC-V QingKe V4F
CH32F103/203	ARM Cortex-M3
CH552/554/559	8051 Enhanced

Interface Type Detection

The handler provides

getInterfaceType()

for interface chips:

Series	Interface Type
CH340, CH9340	USB to UART
CH341	USB to UART/I2C/SPI/Parallel
CH348	USB to 8x UART
CH395	Ethernet Controller
CH9121	Ethernet to UART
CH9141/9143	BLE to UART
CH334	USB Hub Controller
CH224	USB PD Controller

---

Related Files

• Handler:

  manufacturers/WCHHandler.java

• Component types:

  MICROCONTROLLER

  ,

  IC

---

CH340 vs CH340C

The CH340C has an integrated crystal oscillator:

• CH340G: Requires external 12MHz crystal
• CH340C: No external crystal needed (recommended for new designs)

Both are SOP-16 package and pin-compatible.

---

STM32 Compatibility

CH32F103 series is designed as a drop-in replacement for STM32F103:

• Same pinout and package options
• Same peripheral registers
• Lower cost alternative
• Note: Not 100% register-compatible, test thoroughly

---

Learnings & Edge Cases

• QingKe cores: WCH's proprietary RISC-V core implementations (V2A, V3A, V4B, V4C, V4F)
• CH32V003 popularity: Entry-level RISC-V MCU, extremely low cost (~$0.10)
• CH340 dominance: Most common USB-UART chip in Arduino clones and hobbyist boards
• Position-based extraction: MCU pin code at position 8, flash at position 9
• Flash code reuse: Same encoding as STM32 (8=64KB, B=128KB, C=256KB)
• CH32F vs STM32F: Pin-compatible but register differences exist, verify before migration
• Temperature code: 6 = industrial (-40 to +85C) is standard for all CH32 MCUs

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