CH341_EN.pdf

(203 KB) Pobierz
The DataSheet of CH341 (the first)
1
USB bus convert chip CH341
English DataSheet
Version:2D
http://wch.cn
http://wch-ic.com
1. Introduction
CH341 is a USB bus convert chip, providing UART, printer port, parallel and synchronous serial with
2-wire or 4-wire through USB bus.
In UART mode, CH341 provides alternant rate control signals such as serial transfer enable, serial
receive in ready etc. It also supplies common MODEM communication signal in order to expand UART for
computer or upgrade common synchronous interface device to USB bus directly.
In printer port mode, CH341 supplies standard USB printer port which compounds USB relevant
protocol and Windows operate system used to upgrade ordinary parallel printer to USB bus directly.
In parallel mode, CH341 gives out 8-bit parallel in EPP or MEM mode. It can be used to input/output
data directly without MCU/DSP.
Besides, CH341A also supports some common synchronous serial such as 2-wire (SCL, SDA) and
4-wire (CS, SCK/CLK, MISO/SDI/DIN and MOSI/SDO/DOUT) interface.
UART/RS232/RS485/RS422
D+
D-
CH341
Convert chip
Parallel printer to USB printer
Computer
and other
USB host
EPP parallel and MEM parallel
Common 2-wire and 4-wire synchronous serial
2. Features
2.1.Introduction
●
Full speed USB device interface, conforms to USB Specification Version 2.0, only needs crystal and
capacitance external.
●
Optional: define Vender ID, production ID and list number through external low-cost serial EEPROM.
●
Supports 5V and 3.3V power source.
●
Low-cost, directly convert serial peripheral equipment, parallel printer and parallel peripheral
equipment.
●
SOP-28 and SSOP-20 package lead free, compatible with RoHS.
●
Only compatible with application layer because interfaces are diverted via USB.
The DataSheet of CH341 (the first)
2
2.2. UART
●
Simulate standard serial used to upgrade serial peripheral equipment or increase extra serial via USB.
●
Totally compatible with serial application program of computer Windows operation system.
●
Hardware full-duplex serial, on-chip transform and receive buffer, supports 50bps~2Mbps
communication baud rate.
●
Supporting five, six, seven or eight data bits, supporting odd, even, blank, token and no check.
●
Supporting serial transfer and receive enable and serial receive ready etc transfer speed control signal
and MODEM liaison signal.
●
Providing RS232, RS485 and RS422 interface through adding level switch equipment external.
●
Supporting indirectly access to outside serial EEPROM memory through standard serial
communication.
2.3. Printer port
●
Standard USB printer port used to upgrade parallel printer, conforms to relevant USB specification.
●
Compatible with Windows operation system, totally compatible with application program under
Windows 2000 and XP without drive program.
●
Supports various standard parallel printers, low-speed and high-speed print mode are optional.
●
Supports bi-directional communication of IEEE-1284 specification, supports single directional and
bi-directional transfer printer.
2.4. Parallel
●
Providing two interface mode: EPP and MEM.
●
EPP mode supplies AS#, DS# and WR# etc signal, similar with EPP V1.7 or EPP V1.9.
●
MEM mode supplies A0, RD# and WR# etc signal, similar with memory read/write mode.
2.5. Synchronous serial
●
Adopts FlexWire
TM
technology, realize various 2-wire to 5-wire synchronous serial via software.
●
As Host/Master endpoint, supports 2-wire and 4-wire etc common synchronous serial.
●
2-wire interface supplies SCL and SDA signal wire, supports four kinds of transfer speed.
3. Package
The DataSheet of CH341 (the first)
3
Package shape
SOP-28
SSOP-20
SSOP-20
Width of plastic
7.62mm 300mil
5.30mm 209mil
5.30mm 209mil
Pitch of Pin
1.27mm 50mil
Instruction of package
Small outline package of 28-pin
Ordering type
CH341A
CH341T
CH341H
0.65mm 25mil Shrink small outline package of 20-pin
0.65mm 25mil Shrink small outline package of 20-pin
Note: CH341T is only used to USB convert to serial interface or USB convert to 2-wire interface,
CH341H is only used to USB convert to 4-wire interfaces etc. (such as SPI)
4. Pins
4.1.General explanation
The detail function of CH341 is decided by function configuration after reset. The same pin may have
different define under different function.
CH341T and CH341H adopts SSOP-20 package, the simple vision of CH341A, the pins with same pin
name have the same function of them. The multiply VCC pins parallel connect as VCC and multiply GND
pins parallel connect as GND in CH341T and CH341H.
4.2.Standard public pins
Pin No.
341A
28
12
9
341T
13,20
11,12
6
341H
20
7,18
4
Pin Name
VCC
GND
V3
Pin Type
POWER
POWER
POWER
Pin Description
Positive power input port, requires an 0.1uF power
decoupling capacitance
Public ground, ground connection for USB bus
Attachment of VCC input external power while
3.3V;connects of 0.01uF decoupling capacitance
outside while 5V
Input of crystal oscillator, attachment of crystal
and crystal oscillator capacitance external
Opposite output of crystal oscillator, attachment of
crystal and crystal oscillator capacitance outside
Directly connects to D+ data wire of USB bus
Directly connects to D- data wire of USB bus
After USB device configuration output status, low
active
Input of external reset, active with high-level, with
pull-down resistor
Output of chip function configuration, with
pull-up resistor, connect with SCL of serial
EEPROM configuration chip
Input of chip function configuration, with pull-up
resistor, connect with SDA of serial EEPROM
configuration chip
13
14
10
11
1
2
9
10
7
8
1
No
8
9
5
6
1
2
XI
XO
UD+
UD-
ACT#
RSTI
IN
OUT
USB signal
USB signal
OUT
IN
Drain open
Output
drain open
OUT/IN
24
16
No
SCL
23
15
No
SDA
The DataSheet of CH341 (the first)
4
4.3.Asynchronous serial interface pins
Pin No.
341A
5
6
27
25
26
4
15
16
17
18
20
21
19
7
8
3
22
341T
3
4
19
17
18
2
No
No
No
No
No
No
No
5
No
No
14
Pin Name
TXD
RXD
TEN#
RDY#
TNOW
ROV#
CTS#
DSR#
RI#
DCD#
DTR#
RST#
OUT#
INT#
IN3
IN7
SLP#
Pin Type
OUT
IN
IN
OUT
OUT
Tri-state
Output
IN
IN
IN
IN
Tri-state
Output
Tri-state
Output
Tri-state
Output
IN
IN
IN
Tri-state
Output
Pin Description
Serial data output
Serial data input, with pull-up resistor
Serial transfer enable, active with low-level, with pull-up
resistor
Serial receive is ready, low-level active
Indicate serial interface transfer is carrying out, high-level
active
Serial receive buffer overflow, low-level active
MODEM liaison input signal, clear transfer, low-level
active
MODEM liaison input signal, data equipment is ready,
low-level active
MODEM liaison input signal, indication with bell,
low-level active
MODEM communication input signal, carrier wave
detection, low-level active
MODEM liaison output signal, data terminal ready,
low-level active
MODEM liaison output signal, request transferring,
low-level active
Self-define common output signal, low-level active
Self-define interrupt request, rising edge active, with
pull-up resistor
Self-define common input signal, un-connection is
recommended
Self-define common input signal, un-connection is
recommended
Sleep state output signal, low-level active
4.4.Print interface mode pins
341A
Pin No.
22~15
25
4
Pin Name
D7~D0
STB#
AFD#
Pin Type
Tri-state
Output
OUT
OUT
Pin Description
8-bit parallel data output, connect to DATA7~DATA0
Data strobe output, low-level active, connect to STROBE
Automatically feed output, low-level active, connect to
AUTO-FEED
The DataSheet of CH341 (the first)
5
26
3
5
8
6
7
27
INI#
SIN#
ERR#
SLCT
PEMP
ACK#
BUSY
OUT
Tri-state
Output
IN
IN
IN
IN
IN
Initialize printer, low-level active, connect to INIT
Select printer, low-level active, connect to SELECT-IN
Error with printer, low-level active, with pull-up resistor,
connect to ERROR or FAULT
Printer is selected, high-level active, with pull-up resistor,
connect to SELECT or SLCT
Printer is short of papers, high-level active, connect to
PEMPTY or PERROR
Printer data receive answer, active with rising edge, with
pull-up resistor, connect to ACK
Printer is busy, high-level active, with pull-up resistor, connect
to BUSY
4.5.Parallel mode pins
341A
Pin No.
22~15
Pin Name
D7~D0
Pin Type
Bi-directional
tri-state
OUT
Pin Description
8-bit bi-directional data bus, with pull-up resistor
EPP mode: indicate write operation, write with low-level,
read with high-level
MEM mode: write strobe output WR#, low-level active
4
26
3
27
7
5
8
6
DS#
RST#
AS#
WAIT#
INT#
ERR#
SLCT
PEMP
OUT
OUT
Tri-state
Output
IN
IN
IN
IN
IN
EPP mode: data operation select, low-level active
MEM mode: read strobe output RD#, low-level active
Reset output, low-level active
EPP mode: address operation strobe, low-level active
MEM mode: address wire output ADDR or A0
CH341A: request to wait, low-level active, with pull-up
resistor
Interrupt request input, active with rising edge, with
pull-up resistor
Self-define common input, with pull-up resistor
Self-define common input, with pull-up resistor
Self-define common input, with pull-up resistor
25
WR#
4.6.Synchronous serial interface pins
Pin No.
341A
22
21
20
19
341H
17
16
15
14
Pin Name
DIN
DIN2
DOUT
DOUT2
Pin Type
IN
IN
Tri-state
Output
Tri-state
Pin Description
4-wire serial data input, with pull-up resistor
5-wire serial data input 2,with pull-up resistor
4-wire serial data output, other name is MOSI or SDO
5-wire serial data output 2

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika:

Zgłoś jeśli naruszono regulamin