DIO1413/1414

Version 1.2, Sep 2024

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© 2024 DIOO MICROCIRCUITS CO., LTD.

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Figure 10. Typical remote substrate transistor (e.g. CPU substrate PNP or 2N3906)

Figure 11. Typical remote discrete NPN transistor (e.g. 2N3904)

Figure 12. Anti-parallel connected discrete NPN transistors (e.g. 2N3904)

11. Communication Protocol and SMBus Protocol

11.1. Communication protocol

Through the SMBus (or I2C), the DIO1413/1414 can communicate with the host controller. The SMBus is a

two-wire serial communication protocol between a computer host and its peripheral devices. The details can be

found in the Figure 1.

11.1.1. SMBus address and RD/

——

WR bit

The SMBus address byte consists of the 7-bit client address followed by the RD/

——

WR indicator bit. To the client

device, the RD/

——

WR bit can be either writing or reading date.

When the RD/

——

WR bit is a logic ‘0’, the SMBus host is writing data. When the RD/

——

WR bit is a logic ‘1’, the SMBus

host is reading data.

The DIO1413C and DIO1414C SMBus slave address is determined by the pull-up resistor on the

______

THERM/ADDR pin as shown in table 5 in section 9.8 "Programming SMBus (or I2C) Address".

11.1.2. SMBus data bytes

All SMBus data bytes are composed of 8-bits of information and sent in order of priority, which means they are

sent most significant bit at first.

11.1.3. SMBus ACK and NACK bits

All received data bytes are acknowledged by the SMBus client. This is accomplished by the client device pulling

the SMBus data line low after each sent byte's eighth bit. This is true of the Write Byte protocol.