Digital display electric heating furnace automatic temperature controller

This circuit can automatically control the heating of electric heating equipment such as heating furnaces, and use digital display to set (control) the temperature
. It is intuitive, convenient and flexible to operate. The digital display electric heating furnace automatic temperature controller is shown in Figure 1-26.
    The functional principles of AD596/597 are basically similar to AD594/595. Compared with the circuit in Figure 1-25, using
AD596/597, the temperature setting and temperature control circuits are more simplified. The signal is output from the ⑥ pin and divided into three channels: one channel is sent to the
A/D conversion IC 4 for processing, and the temperature value is displayed on the LED digital tube. The other channel is fed to the feedback input pin ⑤ to
form feedback amplification inside IC1. The third path sends a voltage comparator composed of IC2 to
compare the potential of terminal (one) with the potential of terminal (+). When the potential of terminal (one) is lower than the potential of terminal (+), that is, the temperature detected by TC has not reached the predetermined level. Assume
that the temperature
of When, the output of IC2 becomes low level
and heating stops; similarly, after heating stops, when the temperature drops below the predetermined temperature, heating starts automatically again. MA
is used to set the hysteresis voltage, IC 3 provides a +5. OV reference voltage, and RP is used to set the temperature control point and control the temperature
.