FT201XQ-R FTDI, FT201XQ-R Datasheet - Page 15

• Manufacturer Part Number: FT201XQ-R
• Description: USB Interface IC USB to I2C IC QFN-16
• Manufacturer: FTDI

Specifications of FT201XQ-R

• Rohs: yes
• Product: USB 2.0
• Data Rate: 12 Mbps, 480 Mbps
• Interface Type: I2C, USB
• Operating Supply Voltage: 2.97 V to 5.5 V
• Operating Supply Current: 6.4 mA to 8.65 mA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-16
• Tradename: X-Chip

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I
open-drain wires called serial data (SDA) and serial clock (SCL). Common I²C bus speeds are the 100
kbit/s standard mode (SM), 400 kbit/s fast mode (FM), 1 Mbit/s Fast mode plus (FM+), and 3.4 Mbit/s
High Speed mode (HS)
An I
The FT201X device shall only be able to operate as a slave, but is capable of speeds up to 3.4MBit/s.
There are four potential modes of operation for a given bus device, although most devices only use a
single role and its two modes:
The master is initially in master transmit mode by sending a start bit followed by the 7-bit address of the
slave it wishes to communicate with, which is finally followed by a single bit representing whether it
wishes to write(0) to or read(1) from the slave.
If the slave exists on the bus then it will respond with an ACK bit (active low for acknowledged) for that
address. The master then continues in either transmit or receive mode (according to the read/write bit it
sent), and the slave continues in its complementary mode (receive or transmit, respectively).
The address and the data bytes are sent most significant bit first. The start bit is indicated by a high-to-
low transition of SDA with SCL high; the stop bit is indicated by a low-to-high transition of SDA with SCL
high.
If the master wishes to write to the slave then it repeatedly sends a byte with the slave sending an ACK
bit. (In this situation, the master is in master transmit mode and the slave is in slave receive mode.)
If the master wishes to read from the slave then it repeatedly receives a byte from the slave, the master
sending an ACK bit after every byte but the last one. (In this situation, the master is in master receive
mode and the slave is in slave transmit mode.)
The master then ends transmission with a stop bit, or it may send another START bit if it wishes to retain
control of the bus for another transfer (a "combined message").
I²C defines three basic types of message, each of which begins with a START and ends with a STOP:
In a combined message, each read or write begins with a START and the slave address. After the first
START, these are also called repeated START bits; repeated START bits are not preceded by STOP bits,
which is how slaves know the next transfer is part of the same message.
Please refer to the I
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C (Inter Integrated Circuit) is a multi-master serial bus invented by Philips. I
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I
C bus node can operate either as a master or a slave:
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C Interface Description
Master node
Slave node
Master transmit
Master receive – receiving data from a slave
Slave transmit – sending data to a master
Slave receive
Single message where a master writes data to a slave;
Single message where a master reads data from a slave;
Combined messages, where a master issues at least two reads and/or writes to one or more
slaves
Copyright © 2013 Future Technology Devices International Limited
2
C specification for more information on the protocol.
– issues the clock and addresses slaves
– receives the clock line and address.
– receiving data from the master
– sending data to a slave
FT201X USB I2C SLAVE IC Datasheet
Document No.: FT_000627 Clearance No.: FTDI# 264
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C uses two bi-directional
Version 1.3
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