CH340K

WCH (Nanjing Qinheng Microelectronics)

-20℃~+70℃ 2Mbps 3.3V、5V USB 2.0 USB to serial ESSOP-10-150mil-1mm USB Converters ROHS

Extended

Category: USB Converters
Package: ESSOP-10-150mil-1mm
Pins: 11

Overview

The CH340K is a USB Converter made by WCH (Nanjing Qinheng Microelectronics) in a ESSOP-10-150mil-1mm package with 11 pins. -20℃~+70℃ 2Mbps 3.3V、5V USB 2.0 USB to serial ESSOP-10-150mil-1mm USB Converters ROHS.

PCBKit's library has its KiCad symbol (Interface_USB:CH340K, from KiCad's library) and its footprint (Package_SO:SSOP-10-1EP_3.9x4.9mm_P1mm_EP2.1x3.3mm, from KiCad's library), ready for a KiCad board. 33,464 are in stock at JLCPCB (part C968586). 111 open-source boards in 83 repositories on GitHub use it.

Symbol

Interface_USB:CH340KFrom KiCad's library

Footprint

Package_SO:SSOP-10-1EP_3.9x4.9mm_P1mm_EP2.1x3.3mmFrom KiCad's library

From the datasheet

Supply, least: 4 V · VCC, recommended operating min, 5 V mode; V3 capacitor only · p. 5
Supply, most: 5.3 V · VCC, recommended operating max, 5 V mode; V3 capacitor only · p. 5
Supply, least: 3.1 V · VCC, recommended operating min, 3.3 V mode; V3 connected to VCC · p. 5
Supply, most: 3.6 V · VCC, recommended operating max, 3.3 V mode; V3 connected to VCC · p. 5
Supply, absolute maximum: 6 V · VCC, absolute max · p. 5
Works from: -20 °C · Operating ambient min, CH340C/N/K/E/X/B · p. 5
Works up to: 70 °C · Operating ambient max, CH340C/N/K/E/X/B · p. 5
Takes working: 7 mA · VCC, operating typical, 5 V, TA=25℃ · p. 5
Takes working: 4 mA · VCC, operating typical, VCC=V3=3.3 V, TA=25℃ · p. 5
Takes at most: 20 mA · VCC, operating max, 5 V, TA=25℃ · p. 5
Takes at most: 12 mA · VCC, operating max, VCC=V3=3.3 V, TA=25℃ · p. 5
Takes asleep: 90 µA · VCC, USB suspend typical, 5 V, TA=25℃ · p. 5
Takes asleep: 80 µA · VCC, USB suspend typical, VCC=V3=3.3 V, TA=25℃ · p. 5
Data rate, most: 2 Mbit/s · UART baud rate max · p. 1

What it is and has

USB: Full-speed device interface, USB V2.0 compatible · p. 1
UART: Hardware full duplex, transmit and receive buffers, 50bps～2Mbps · p. 1
Clock: Internal clock; no external crystal or oscillator capacitors required · p. 3
Firmware and driver: Built-in firmware, CH341 software compatible, CH341 VCP driver support · p. 1
Protection: Three built-in diodes prevent MCU I/O backfeed into CH340 when separately powered · p. 2
Package: ESSOP-10, 3.9mm / 150mil body width, 1.00mm pitch, exposed bottom pad · p. 2

Around it

cap 0.1uF: between VCC and GND; Power decoupling; place close to the connected CH340 pin. · p. 2
cap 0.1μF: between V3 and GND; Internal 3.3V node decoupling for 5V operation; place close to the pin. · p. 6
res 4.7KΩ: between DTR# and GND; Optional pull-down for default low during USB enumeration to request more USB supply current. · p. 3
res 2KΩ～22KΩ: between MCU RX and MCU VDD; For separately powered MCU connections above 120Kbps; enable the MCU internal pull-up or add this external pull-up. · p. 9

Specifications

Parameter	Conditions	As printed	Page
工作时的环境温度 TA	CH340C/N/K/E/X/B	min -20 · max 70 ℃	5
储存时的环境温度 TS		min -55 · max 125 ℃	5
电源电压（VCC 接电源，GND 接地） VCC		min -0.5 · max 6 V	5
输入或者输出引脚上的电压 VIO	最大值为 VCC+0.5 V	min -0.5 V	5
电源电压 VCC	TA=25℃; V3 引脚仅外接电容，不连 VCC	min 4 · typ 5 · max 5.3 V	5
工作时总电源电流 ICC	TA=25℃，VCC=5V; CH340G/C/N/K/E/X/T/R	typ 7 · max 20 mA	5
USB 挂起时的总电源电流 ISLP	TA=25℃，VCC=5V; CH340G/K/T/R/B	typ 0.09 · max 0.2 mA	5
低电平输入电压 VIL	TA=25℃，VCC=5V，不包括连接 USB 总线的引脚	min 0 · max 0.9 V	5
高电平输入电压 VIH	TA=25℃，VCC=5V，不包括连接 USB 总线的引脚; 最大值为 VCC	min 2.3 V	5
低电平输出电压 VOL	TA=25℃，VCC=5V，不包括连接 USB 总线的引脚; 6mA 吸入电流	max 0.5 V	5
内置上拉电阻的输入端的输入电流 IUP	TA=25℃，VCC=5V，不包括连接 USB 总线的引脚	min 3 · typ 150 · max 300 uA	5
内置下拉电阻的输入端的输入电流 IDN	TA=25℃，VCC=5V，不包括连接 USB 总线的引脚	min -40 · typ -100 · max -300 uA	5
电源上电复位的电压门限 VR	TA=25℃，VCC=5V	min 2.4 · typ 2.6 · max 2.8 V	5
电源电压 VCC	TA=25℃; V3 引脚连接 VCC 引脚; CH340C/N/K/E/X/B	min 3.1 · typ 3.3 · max 3.6 V	5
工作时总电源电流 ICC	TA=25℃，VCC=V3=3.3V; CH340G/C/N/K/E/X/T/R	typ 4 · max 12 mA	5
USB 挂起时的总电源电流 ISLP	TA=25℃，VCC=V3=3.3V; CH340G/K/T/R/B	typ 0.08 · max 0.2 mA	5
低电平输入电压 VIL	TA=25℃，VCC=V3=3.3V，不包括连接 USB 总线的引脚	min 0 · max 0.8 V	5
高电平输入电压 VIH	TA=25℃，VCC=V3=3.3V，不包括连接 USB 总线的引脚; 最大值为 VCC	min 1.9 V	5
低电平输出电压 VOL	TA=25℃，VCC=V3=3.3V，不包括连接 USB 总线的引脚; 4mA 吸入电流	max 0.5 V	5
内置上拉电阻的输入端的输入电流 IUP	TA=25℃，VCC=V3=3.3V，不包括连接 USB 总线的引脚	min 3 · typ 70 · max 200 uA	5
内置下拉电阻的输入端的输入电流 IDN	TA=25℃，VCC=V3=3.3V，不包括连接 USB 总线的引脚	min -30 · typ -70 · max -200 uA	5
电源上电复位的电压门限 VR	TA=25℃，VCC=V3=3.3V	min 2.4 · typ 2.6 · max 2.8 V	5
内部时钟的误差（同比影响波特率） FD	VCC=5V 或 3.3V; CH340C/N/K/E/X/B; TA=-5℃～55℃; 典型值为 ±0.8%	min -1.2 · max 1.2 %	6
内部时钟的误差（同比影响波特率） FD	VCC=5V 或 3.3V; CH340C/N/K/E/X/B; TA=-25℃～75℃; 典型值为 ±1.0%	min -1.8 · max 1.8 %	6
电源上电的复位时间 TPR	TA=25℃，VCC=5V 或 3.3V	min 20 · typ 35 · max 50 mS	6

Pins, by the datasheet

0 GND: 底板公共接地端，可选择连接 GND 或悬空。 · p. 2
1 UD+: 直接连到 USB 总线的 D+数据线，不要串联电阻。 · p. 2
2 UD-: 直接连到 USB 总线的 D-数据线，不要串联电阻。 · p. 2
3 GND: 公共接地端，必须直接连到 USB 总线的地线。 · p. 2
4 DTR#: MODEM 数据终端就绪输出，低电平有效；普通推挽输出，无防倒灌二极管。 · p. 3
5 CTS#: MODEM 清除发送输入，低电平有效，内置上拉电阻，无防倒灌二极管。 · p. 2
6 RTS#: MODEM 请求发送输出，低电平有效；内置防内灌二极管和弱上拉。 · p. 3
7 VCC: 正电源输入端，需要外接 0.1uF 电源退耦电容。 · p. 2
8 TXD: 串行数据输出，空闲为微弱高电平，内置防内灌二极管。 · p. 2
9 RXD: 串行数据输入，内置可控上拉和下拉电阻及防内灌二极管。 · p. 2
10 V3: 3.3V 供电时连接 VCC 输入外部电源；5V 供电时外接 0.1uF 退耦电容。 · p. 2

Ordering codes, by the datasheet

CH340K: ESSOP-10 · 3.9mm / 150mil body width, 1.00mm pitch, bottom pad; internal clock and three backfeed-prevention diodes · p. 2

Parameters

Applications Function: USB to serial
Current - Supply: 7mA
Current - Supply(Max): 20mA
Data Rate: 2Mbps
Features: Programmable baud rate；Built-in clock generator；Power-off protection；Power-on reset
Operating Temperature: -20℃~+70℃
Standby Current: 90uA
USB Protocol: USB 2.0
Voltage - Supply: 3.1V~5.3V
Voltage - Supply(Absolute Max): 6V

Order codes

CH340KLCSC C18208922
CH340KLCSC C968586

Pinout

The pins of the CH340K
Pin	Name	Type
1	UD+	Input/output
2	UD-	Input/output
3	GND	Power in
4	DTR	Output
5	CTS	Input
6	RTS	Output
7	VCC	Power in
8	TXD	Output
9	RXD	Input
10	V3	Passive
11	GND	Passive

Open-source boards using it

All 111

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Npr revB
slintak/NPR70
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Watch full video on ESP32 surveillance car
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Downloader
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a cheap usb to ttl hardware for esp8266 or esp32
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2 layers128 × 70.5 mm
EL6170 Pro Max Plus
jsjsjsjsjsjsjson/EL6170_Pro_Max_Plus

164 parts7

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Questions

Is there a KiCad symbol and footprint for the CH340K?

Yes. The symbol is Interface_USB:CH340K and the footprint Package_SO:SSOP-10-1EP_3.9x4.9mm_P1mm_EP2.1x3.3mm, both drawn on this page. PCBKit places them on a board for you when you design with it.

What package is the CH340K?

ESSOP-10-150mil-1mm, with 11 pins. Its footprint is drawn on this page.

Where is the CH340K datasheet?

WCH (Nanjing Qinheng Microelectronics) publishes it: the Datasheet link on this page opens it.

Where can I order the CH340K?

JLCPCB lists it as part C968586, with 33,464 in stock; the sellers' links on this page open their listings.

What can replace the CH340K?

Parts like it in the library: the CH224K by WCH (Nanjing Qinheng Microelectronics). Check their datasheets: a part that fits the footprint may still differ in its ratings.

Which open-source boards use the CH340K?

111 boards in 83 repositories on GitHub; the most starred are listed on this page, with their KiCad files.

Parts like it

CH224K
ESSOP-10-150mil-1mm-40℃~+90℃ 100W 4V~30V 5V、9V、12V、15V、20V Overvoltage Protection、Thermal Protection PD 3.0 Power Receiver Controller ESSOP-10-150mil-1mm USB PD ROHSWCH (Nanjing Qinheng Microelectronics)USB Converters