C8051F50x-F51x
7. Temperature Sensor
An on-chip temperature sensor is included on the C8051F50x-F51x devices which can be directly
accessed via the ADC multiplexer in single-ended configuration. To use the ADC to measure the tempera-
ture sensor, the ADC multiplexer channel should be configured to connect to the temperature sensor. The
temperature sensor transfer function is shown in Figure 7.1. The output voltage (VTEMP) is the positive
ADC input is selected by bits AD0MX[4:0] in register ADC0MX. The TEMPE bit in register REF0CN
enables/disables the temperature sensor, as described in SFR Definition 8.1. While disabled, the tempera-
ture sensor defaults to a high impedance state and any ADC measurements performed on the sensor will
result in meaningless data. Refer to Table 5.10 for the slope and offset parameters of the temperature sen-
sor.
VTEMP = (Slope x TempC) + Offset
TempC = (VTEMP - Offset) / Slope
Slope (V / deg C)
Offset (V at 0 Celsius)
Temperature
Figure 7.1. Temperature Sensor Transfer Function
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Rev. 1.1
SILICON [ SILICON ]
