C8051F320-TB Silicon Laboratories Inc, C8051F320-TB Datasheet - Page 41

• Manufacturer Part Number: C8051F320-TB
• Description: BOARD PROTOTYPING W/C8051F320
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F320-TB

• Contents: Board
• Processor To Be Evaluated: C8051F320/F321
• Interface Type: USB
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: C8051F320
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

5.2.
The temperature sensor transfer function is shown in Figure 5.2. The output voltage (V
ADC input when the temperature sensor is selected by bits AMX0P4-0 in register AMX0P. Values for the
Offset and Slope parameters can be found in Table 5.1.
The uncalibrated temperature sensor output is extremely linear and suitable for relative temperature mea-
surements (see Table 5.1 for linearity specifications). For absolute temperature measurements, offset and/
or gain calibration is recommended. Typically a 1-point (offset) calibration includes the following steps:
Figure 5.3 shows the typical temperature sensor error assuming a 1-point calibration at 25 °C. Note that
parameters which affect ADC measurement, in particular the voltage reference value, will also
affect temperature measurement.
Temperature Sensor
Step 1. Control/measure the ambient temperature (this temperature must be known).
Step 2. Power the device, and delay for a few seconds to allow for self-heating.
Step 3. Perform an ADC conversion with the temperature sensor selected as the positive input
Step 4. Calculate the offset characteristics, and store this value in non-volatile memory for use
and GND selected as the negative input.
with subsequent temperature sensor measurements.
Figure 5.2. Temperature Sensor Transfer Function
V
Temp
TEMP
C
=
= (V
(Gain
TEMP
x Temp
- Offset) /
Temperature
Rev. 1.4
C
) +
Offset
Offset
Gain
(V at 0 Celsius)
Gain
(V / deg C)
C8051F320/1
TEMP
) is the positive
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