2 ] Ambient Temperature Sensor Circuit - Brother PT-1800 Service Manual

Figure 3.2-12 Voltage Detector Circuit

[ 2 ] Ambient temperature sensor circuit

This circuit is composed of a resistor R13 and a thermistor TH1. It converts the
resistance of TH1 (whose internal resistance varies depending upon the ambient
temperature) to the voltage variation, and then feeds its output to the A/D input port PA0
on the CPU. According to the Ambient temperature data, the CPU determines the
optimum head drive power.
Figure 3.2-13 Ambient Temperature Sensor Circuit
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