Table 7-5. Address Pin and Device Target Address

DEVICE TARGET ADDRESS1

ADD0 PIN CONNECTION

DEVICE ORDERABLE

1001000

GND

TMP113

1001001

VDD

1001010

SDA

1001011

SCL

7.5.4 Bus Transactions

7.5.4.1 Writes

To write on the I2C bus, the controller sends a START condition on the bus with the address of the target, as well

as the last bit (the R/W bit) set to 0b, which signifies a write. The target acknowledges, letting the controller know

the target is ready. After this operation, the controller starts sending the register pointer and data to the target,

and the controller terminates the transmission with a STOP condition.

Writes to read-only registers or register locations outside of the register map are ignored. The TMP113 still

performs and acknowledges when writing outside of the register map. Figure 7-7 shows an example of writing a

single word write communication.

Controller drives SDA

Target drives SDA

S

A6

A5

A4

A3

A2

A1

A0

0

A

0

0

0

0

P3

P2

P1

P0

A

D15

D14

D13

D12

D11

D10

D9

D8

A

D7

D6

D5

D4

D3

D2

D1

D0

A

P

START

R/W

ACK from Target

ACK from Target

ACK from Target

ACK from Target

STOP

Target Address

Register Pointer (N)

Data to Register N (MSB)

Data to Register N (LSB)

Figure 7-7. Write to Single Register

7.5.4.2 Reads

For a read operation the controller sends a START condition, followed by the target address with the R/W bit

set to 0b (signifying a write). The target acknowledges the write request, and the controller sends the Register

Pointer. The controller initiates a restart followed by the target address with the R/W bit set to 1b (signifying a

read). The controller continues to send out clock pulses but releases the SDA line so that the target can transmit

data. At the end of every byte of data, the controller sends an ACK to the target, letting the target know that

the controller is ready for more data. For repeated read operations from the same register (like temperature

register), resending the register pointer is not necessary. The read operation from the same register can be

repeated as many time as the controller needs when the pointer is set. Once the controller has received the

expected number of bytes, the controller sends a NACK, signaling to the target to halt communications and

release the SDA line. The controller follows this up with a STOP condition. Reading from a non-indexed register

location returns 00h. Figure 7-8 shows an example of reading a single word from a target register. Note that after

resetting, the pointer is set to zero and the temperature register must be addressed.

1 Additional address options can be available on request

TMP113

SBOSAJ5 – DECEMBER 2024

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