User's Manual

Smart Machine Smart Decision
SIM5320A_Hardware Design_V1.01 2011-2-29
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Temperature monitor
ADC interface can be used to monitor the temperature of power components to avoid over temperature. An
external NTC resistor (such as NCP15XH103F03RC) can be used to measure the device temperature. The
ADC1 pin can be used as external voltage detection. Please refer to Chapter 3.17. ADC2 is the ADC input
pin for temperature detection. The following figure shows the application circuit.
Figure 11: Internal circuit
From above figure, the input voltage can be calculated:
Vadc=2.2* Rt/Rt+9.76 (V) Rt is a NTC thermistor.
The default temperature
VS Va dc voltage table is shown below.
Table 6: Temperature table
Temperature degree()
Vadc (mV)
-30 1887
-20 1814
-10 1711
0 1574
10 1408
20 1224
30 1035
40 856
50 695
60 558
70 446
80 355