Rice cooker preset power-off timer circuit

(1) Introduction to the circuit principle Figure 3-29 shows the preset power-off timing circuit of the rice cooker. The timing range of this timing circuit is th-12h
and can be adjusted by RP. The timing mode is counting mode, and the control mode is preset power-off timing. BT33 is used in the circuit to generate the trigger signal of thyristor VT
. If BT33 stops vibrating, VT is turned off and cz is powered off.
    (2) Component parameter selection The selection of components is shown in Figure 3-29, and there are no special requirements.
    (3) The rice cooker preset power-off timer circuit is shown in Figure 3-29.