TMD37821 datasheet(14/34 Pages) AMSCO

14 / 34 page

TMD3782 – 14

Datasheet - Mar. 2013 - V2

Interface and control are accomplished through an I2C serial

compatible interface (standard or fast mode) to a set of registers

that provide access to device control functions and output data.

The devices support the 7-bit I2C addressing protocol.

The I2C standard provides for three types of bus transaction:

read, write, and a combined protocol (Figure TMD3782 - 23).

During a write operation, the first byte written is a command

byte followed by data. In a combined protocol, the first byte

written is the command byte followed by reading a series of

bytes. If a read command is issued, the register address from

the previous command will be used for data access. Likewise, if

the MSB of the command is not set, the device will write a series

of bytes at the address stored in the last valid command with a

information or a 5-bit register address. The control commands

can also be used to clear interrupts.

The I2C bus protocol was developed by Philips (now NXP). For

a complete description of the I2C protocol, please review the

NXP I2C design specification at

http://www.i2c-bus.org/references/.

Figure TMD3782 – 23:

I2C Write, Read and Combined Protocols

I2C Protocol

Acknowledge (0)

Not Acknowledged (1)

Stop Condition

Read (1)

Start Condition

Repeated Start Condition

Write (0)

Continuation of Protocol

Master - to - Slave

Slave -to -Master

TMD37821 Datasheet(PDF) 14 Page - ams AG