MRF39RA datasheet(19/72 Pages) MICROCHIP

19 / 72 page

 2015 Microchip Technology Inc.

DS40001778B-page 19

MRF39RA

2.4.18

TEMPERATURE SENSOR

When temperature is measured, the receiver ADC is

used to digitize the sensor response. Most receiver

blocks are disabled, and temperature measurement

can only be triggered in Standby or Frequency

Synthesizer modes.

As shown in Figure 2-11, the response of the

temperature sensor is -1°C/Lsb. A CMOS temperature

sensor is not accurate by nature; therefore, it must be

calibrated at ambient temperature for precise

temperature readings.

FIGURE 2-11:

TEMPERATURE SENSOR RESPONSE

It takes less than 100 microseconds for the MRF39RA

evaluate

the

temperature

from

setting

TempMeasStart to ‘1’ to TempMeasRunning Reset.

2.4.19

TIME-OUT FUNCTION

The MRF39RA includes a time-out function, which

enables it to automatically shut down the receiver after

a receive sequence and, therefore, save energy.

• Time-out interrupt is generated,

TimeoutRxStart x 16 x Tbit, after switching to RX

mode if RssiThreshold flag does not raise within

this time frame.

• Time-out interrupt is generated,

TimeoutRssiThresh x 16 x Tbit, after

RssiThreshold flag is raised.

Use Time-out interrupt to warn the companion

processor to shut down the receiver and return to a

lower power mode.

-40

°C

+85

°C

TempValue

Ambient

Returns 150d (typ.)

Needs calibration

tt+1

TempValue(t)

TempValue(t)-1

-1

°C/Lsb

MRF39RA Datasheet(PDF) 19 Page - Microchip Technology

MRF39RA Datasheet(HTML) 19 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72

Datasheet Download

Link URL