Rev1.0 | Page 7/11

T06

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5. I2C Interface

The T06 complies with “fast” mode I2C operation and 7-bit addressing at speeds up to 400 kHz.

The I2C address is factory programmed to one of 4 values 0x30, 0x31, 0x32, or 0x33 (0110000b through

0110011b).

At power-up the registers are initialized, as will be described in the register definitions, and then they can be

read or written in standard fashion for I2C devices.

The host command for writing an I2C register is:

START Address W ACK Register ACK data ACK STOP

The host command for reading an I2C register is:

START Address W ACK register ACK Sr Address R Data NACK* STOP

*NACK by host

Where:

START is SDA going low with SCL high

Sr is a repeated START

Address is 0x30 up to 0x33.

0 indicates a write and 1 indicates a read.

ACK is SDA low.

Data is the Read or Write data.

NACK is SDA high.

STOP is SDA going high with SCL high.

Writing or Reading of sequential registers can be supported by setting the arautoinc bit of register 0xC5 (see

register description). In the case of a read sequence where the arautoinc bit has been set, the data can be

ACK’d to allow reading of sequential registers. For example, a two byte read of the conversion data in registers

0xC1 and 0XC2 would be:

START Address W ACK 0xC1 ACK Sr Address ACK data ACK* data NACK* STOP

*ACK/NACK by host

To wake a part from sleep mode or to interrupt a measurement loop from idle mode, send the sequence:

START Address W ACK STOP

In this case, if the host continued with a register write, the T06 would NACK which would be unexpected.

Additionally, the following sequence can be used to wake the part up or to interrupt a measurement loop:

START Address R ACK data NACK* STOP

*NACK by host

In this case, the T06 will produce 0xFF

for the data. Allow for 10 μs between the ACK of the address and the

next START for the T06 to wake from sleep. In most cases, this will happen automatically, due to the 400 KHz

maximum speed of the I2C bus. The sequence will put the part in idle mode with the stop bit set.

To make a single conversion, having woken the part, set the oneburst bit of register 0xC4 to 1 and the stop bit

to 0. The stop bit resets to 1 by the time the measurement is complete.

To put the part back to sleep after reading the data, set the stop bit to 0.

Putting the part to sleep with the sleep bit = 0 will result in the mode of operation where the temperature is

sampled every 200 ms, and the output pin will toggle at the temperature threshold points as defined by

registers 0xC6 and 0xC7 (assuming the usestore bit is also set)—that is, write 0x08 to 0xC4.

If ultra-low power sleep with no sampling is desired, set the stop bit to 0 and the sleep bit to 1—that is, write

0x00 or 0x09 (to retain the settings of 0xC6 and 0xC7) to 0xC4.