component

CH344L

Public Made by Adom

by adom

WCH Jiangsu Qin Heng USB Converters, LQFP-48(7x7). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.

componentinterfacech344lfactory-2.0.0extractor-text
Overview Files Discover Packages Releases Dependencies Issues Breadcrumbs Pull Requests Activity
main
Download ZIP Propose a change
Generated by kicad-footprint-generator · KiCad file format 20260206
Name Last commit message Last updated
docs Publish 0.1.0 · Ray 8d ago
viewers ch344l: viewers · Ray 8d ago
ch344l-etched.glb Publish 0.1.0 · Ray 8d ago
ch344l-etched.step ch344l: factory component page (tier=lcsc) · Ray 8d ago
ch344l-hero.glb ch344l: hero GLB from the etched model (keeps the MPN mark) · Ray 8d ago
ch344l-hero.overlay.json Publish 0.1.0 · Ray 8d ago
ch344l.glb Publish 0.1.0 · Ray 8d ago
ch344l.kicad_mod Publish 0.1.0 · Ray 8d ago
ch344l.kicad_sym Publish 0.1.0 · Ray 8d ago
ch344l.lbr Publish 0.1.0 · Ray 8d ago
ch344l.step Publish 0.1.0 · Ray 8d ago
package.json Publish 0.1.0 · Ray 8d ago
page.json Set visibility: public · Ray 8d ago
README.md Publish 0.1.0 · Ray 8d ago

CH344L

WCH Jiangsu Qin Heng · USB Converters · LQFP-48(7x7)

CH344L from WCH Jiangsu Qin Heng, in a LQFP-48(7x7). Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 NC unconnected No connect; must be left floating on CH344L.
2 CFG2 input CH344L TNOW/DTR function select: high or floating at power-up makes all DTRx/TNOWx pins TNOW, low makes them DTR, and individual ports can be set to TNOW with a 4.7kΩ pull-down on their DTRx/TNOWx pin.
3 NC unconnected No connect; must be left floating on CH344L.
4 NC unconnected No connect; must be left floating on CH344L.
5 XI input Crystal oscillator input; an 8MHz crystal with ~22pF load capacitors to GND is recommended, and CH344L may use its internal clock if the crystal is omitted at the cost of larger baud-rate error.
6 XO output Crystal oscillator inverting output; connects to the other side of the 8MHz crystal with its ~22pF load capacitor to GND.
7 RESET input External reset input, active low, with internal pull-up (RPU typ. 40kΩ, range 30-60kΩ).
8 GND power_in Common ground; must be connected to the USB bus ground.
9 VCC power_in Positive supply input at 3.0-3.6V (3.3V typical), decoupled to GND with a ~0.1µF capacitor.
10 CTS1/GPIO2 input UART1 modem input CTS, active low, also usable as general-purpose GPIO2 and for hardware flow control.
11 RTS1/GPIO3 output UART1 modem output RTS, active low, also general-purpose GPIO3.
12 TXD1 output UART1 serial data output, idle high.
13 RXD1 input UART1 serial data input with internal pull-up.
14 ACT output USB configuration complete status output, active low.
15 TX_S output Serial data transmit status output; outputs a 200ms-period pulse while any UART is transmitting.
16 RX_S output Serial data receive status output; outputs a 200ms-period pulse while any UART is receiving.
17 NC unconnected No connect; must be left floating on CH344L.
18 DTR1/TNOW1/GPIO9 bidirectional UART1 modem output DTR (active low) or RS485 TNOW1 transmit/receive control, selected at power-up by CFG2; also general-purpose GPIO9.
19 DTR2/TNOW2/GPIO10 bidirectional UART2 modem output DTR (active low) or RS485 TNOW2 transmit/receive control, selected at power-up by CFG2; also general-purpose GPIO10.
20 GND power_in Common ground; must be connected to the USB bus ground.
21 TXD2 output UART2 serial data output, idle high.
22 RXD2 input UART2 serial data input with internal pull-up.
23 GND power_in Common ground; must be connected to the USB bus ground.
24 VCC power_in Positive supply input at 3.0-3.6V (3.3V typical), decoupled to GND with a ~0.1µF capacitor.
25 NC unconnected No connect; must be left floating on CH344L.
26 CTS2/GPIO4 input UART2 modem input CTS, active low, also general-purpose GPIO4.
27 RTS2/GPIO5 output UART2 modem output RTS, active low, also general-purpose GPIO5.
28 NC unconnected No connect; must be left floating on CH344L.
29 TXD3 output UART3 serial data output, idle high.
30 TXD0 output UART0 serial data output, idle high.
31 RXD0 input UART0 serial data input with internal pull-up.
32 UD- bidirectional USB D- data line, connected directly to the USB bus D- with no series resistor allowed.
33 UD+ bidirectional USB D+ data line, connected directly to the USB bus D+ with no series resistor allowed.
34 NC unconnected No connect; must be left floating on CH344L.
35 GND power_in Common ground; must be connected to the USB bus ground.
36 VCC power_in Positive supply input at 3.0-3.6V (3.3V typical), decoupled to GND with a ~0.1µF capacitor.
37 NC unconnected No connect; must be left floating on CH344L.
38 CFG input Hardware flow control enable, active low, with internal pull-up.
39 DTR0/TNOW0/GPIO8 bidirectional UART0 modem output DTR (active low) or RS485 TNOW0 transmit/receive control, selected at power-up by CFG2; also general-purpose GPIO8.
40 RTS0/GPIO1 output UART0 modem output RTS, active low, also general-purpose GPIO1; if pulled low at power-up, internal EEPROM configuration is disabled and chip default parameters are used.
41 CTS0/GPIO0 input UART0 modem input CTS, active low, also general-purpose GPIO0.
42 RXD3 input UART3 serial data input; requires an external pull-up resistor on CH344L.
43 DTR3/TNOW3/GPIO11 bidirectional UART3 modem output DTR (active low) or RS485 TNOW3 transmit/receive control, selected at power-up by CFG2; also general-purpose GPIO11.
44 TEST input Internal test pin; connect to GND through a pull-down (typ. 4.7kΩ) or tie directly to GND.
45 RTS3/GPIO7 output UART3 modem output RTS, active low, also general-purpose GPIO7.
46 CTS3/GPIO6 input UART3 modem input CTS, active low, also general-purpose GPIO6.
47 GND power_in Common ground; must be connected to the USB bus ground.
48 VCC power_in Positive supply input at 3.0-3.6V (3.3V typical), decoupled to GND with a ~0.1µF capacitor.

Key specifications

Parameter Value
Manufacturer WCH Jiangsu Qin Heng
Package LQFP-48(7x7)
Category Interface
Pins 48

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
Supply voltage (VCC) VCC 3 3.3 3.6 V TA=25℃，VCC=3.3V，不含 USB 引脚 7
Operating supply current, CH344L ICC 12 18 24 mA TA=25℃，VCC=3.3V，不含 USB 引脚 7
USB suspend supply current, CH344L ISLP 200 450 600 uA TA=25℃，VCC=3.3V，不含 USB 引脚 7
Low-level input voltage VIL 0 0.8 V TA=25℃，VCC=3.3V，不含 USB 引脚 7
High-level input voltage VIH 2 V TA=25℃，VCC=3.3V，不含 USB 引脚 7
High-level input voltage, 5V-tolerant pins VIH5 2 5 V TA=25℃，VCC=3.3V，不含 USB 引脚 7
Output low voltage VOL 0.4 V 单个引脚吸入 8mA 电流 7
Internal pull-up equivalent resistance RPU 30 40 60 KΩ TA=25℃，VCC=3.3V，不含 USB 引脚 7
Power-on/power-down reset threshold voltage VPOR 1.9 2.2 2.5 V TA=25℃，VCC=3.3V，不含 USB 引脚 7
ESD withstand voltage, human body model, non-contact (CH344L) VESD 3 KV 人体模型，非接触式 7
Internal clock error, TA=0℃ to 70℃ (CH344L) FD -1.5 0.8 1.5 % TA=0℃～70℃ 7
Internal clock error, TA=-40℃ to 85℃ (CH344L) FD -2 1.5 2 % TA=-40℃～85℃ 7
Reset delay after power-on or external reset TRSTD 15 30 45 mS TA=25℃，VCC=3.3V 7
USB auto-suspend detection time TSUSP 3 5 9 mS TA=25℃，VCC=3.3V 7
Wake-up completion time after sleep TWAKE 0.3 0.5 4 mS TA=25℃，VCC=3.3V 7
Operating ambient temperature TA -40 85 ℃ 工作时的环境温度 6
Storage ambient temperature TS -40 105 ℃ 储存时的环境温度 6
Supply voltage (VCC pin, GND grounded) VCC -0.3 4 V VCC 引脚供电，GND 引脚接地 6
Voltage on USB signal pins VUSB -0.5 3.8 V USB 信号引脚 6
Voltage on 5V-tolerant serial pins VIO5V -0.5 5.6 V 耐受 5V 的串口引脚 6

CAD (KiCad official)

  • Symbol: CH344L
  • Footprint: Package_QFP:LQFP-48_7x7mm_P0.5mm
  • 3D model: LQFP-48(7x7) (KiCad packages3D, STEP)
  • 3D model files: ch344l-etched.step / ch344l-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); ch344l.step / ch344l.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: WCH Jiangsu Qin Heng datasheet (8 pp, sha256 9044ddf347f308c1, retrieved 2026-10-19, tier: lcsc)
  • Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF