Table 27

(continued) Structure of SENT status nibble

Bits

Description

[3] MSB

Short serial message bit (start indication) or 0 if SSM is

disabled 

 

Note:

For more information about the warning bit and the error indication bit please consult the TLE49SR user

manual.

Checksum nibble details

The checksum nibble is a 4-bit CRC of the data nibbles. Optionally the status nibble can be included by register

setting. The CRC is calculated using a polynomial x4 +x3 +x2 +1 with a seed value of 0101B. The remainder after the last

data nibble is transmitted as CRC.

 

Short serial message

The short serial message is an additional option which can be enabled and disabled. The short serial message

provides additional information in the status nibble by transmitting an 8 bit temperature value, and a 52 bit user and

sensor ID.

1 short serial message will be constructed out of 16 SENT frames. In each SENT frame, one bit of information is

transmitted in bit [2] of the status nibble and has following structure:

•

4 bit message ID

•

8 bit data

•

4 bit CRC (calculated from message ID and data bits)

The start of the short serial message is indicated by a “1” in bit [3] of the status nibble. For the next 15 frames, this bit

will contain a “0”.

The message ID is used for identification of the type of data received. All data are transmitted in the bit [2] of the

status nibble in the order MSB to LSB.

 

Rolling counter

The rolling counter counts the number of transmitted frames with rollover back to 0 and increment with each

message. This counter is for verification in the ECU that no frame is missed or that no frame is sent repeatedly from

the sensor.

 

Temperature information

The temperature is coded as an 8 bit value. This value is transferred in unsigned integer format and corresponds to

the range between -55°C and +200°C, so a transferred value of 55 corresponds to 0°C. The following table shows the

mapping between junction temperature and the transmitted value.

Table 28

Mapping of temperature value

Junction temperature

Typical decimal value from sensor

Note

-55°C

0 LSB

theoretical lower limit

0°C

55 LSB

-

25°C

80 LSB

-

200°C

255 LSB

theoretical upper limit

 

Pause Pulse

There is an optional pause pulse which can be activated or deactivated via corresponding bits in the register.

TLE49SR

Datasheet

5  Specific module descriptions

Datasheet

23

Rev. 1.1.1

2024-03-13