3.8.2 Temperature Measurement

When triggering a temperature measurement, the AD converter of the ATA8210/15 operates as a temperature sensor in the range of -40°C to +125°C with a resolution of 1K. The temperature is measured on a specific temperature measurement channel with fLO = 422 MHz. The result of the AD converter is provided in the TEMPH and TEMPL hardware registers, then copied to the calib.sramTEMPH/L SRAM variables by the firmware.

In a subsequent step, a temperature value is calculated and stored to the calib.tempMeas SRAM variable. The valid range of tempMeas is 0-175. Calculate the actual temperature in °C by using the following formula:

T = tempMeas – 50 (2)

Equation parameters:

T – Current temperature [°C]

tempMeas – Content of the calib.tempMeas SRAM variable

Address

Name

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

0x02D9

sramTEMPH

Temperature high byte

0x02DA

sramTEMPL

Temperature low byte

0x02DB

tempMeas

8-bit temperature measurement result (valid range 0-175)

Use the result of the calculation as input for the XTO temperature compensation (RF calibration). See RF Calibration from Related Links.

Use the Read SRAM/Register SPI command to read out the calculated temperature from the calib.tempMeas SRAM variable.

A temperature measurement process can be triggered at the following time points:

  • After power-on during system initialization when enabled in eepConfValid.confInitFlags.TempMeas.

Address

Name

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

0x0008

confInitFlags

—

TempMeas

SRC

FRC

————
  • During the periodic self-check in PollingMode or during a self-check that is started by using the Calibrate and Check SPI command if enabled in eepTrxCal.calConf1.EN_TEMP_MEAS.
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0x001C calConf1 —EN_TEMP_MEAS EN_SRCCAL EN_FRCCAL ———EN_REGREFRESH
  • From IDLEMode via the Calibrate and Check SPI command if bit EN_TEMP_MEAS in tuneCheckConfig is set to ‘1’. See Calibrate and Check from Related Links.
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
tuneCheckConfig —EN_TEMP_MEAS EN_SRCCAL EN_FRCCAL EN_VCOCAL —EN_SELFCHECK —

Setting the TEMP_MEAS bit within the eepEventConf.cmdRdyConf command ready variable to ‘1’ raises a command ready (CMD_RDY) event on the PB6 EVENT pin when finishing the temperature measurement process.

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0x0096 cmdRdyConf —TEMP_MEAS SRC_CAL FRC_CAL VCO_CAL RF_CAL SELFCHECK —

The temperature measurement requires additional time. See Timing Characteristics from Related Links.