Jiale Shi GD929B computer type double temperature mini water dispenser circuit

Crystal patch M49SMD Mini S 4*7 24MHZ 24.000M

Single chip microcomputer STM32L151CCU6

The circuit shown below works as follows:

Turn on the power, 220V power supply through RI, Cv1 buck current limit, VD1 ~ VD4 full-wave rectification, C1 and C5 filter, VS1 voltage regulator, get 12V DC voltage, supply control circuit. IC1 is the core of the control circuit. The 12V DC voltage is reduced to 4.3V by components such as R4, VS2 and VT1 for IC1 operation. Pins 3 and 5 of IC1 are grounded, pins 16 and 5 are connected to the crystal, and pin 18 is connected to the positive terminal through R7. When the power is turned on, the indicator LED-P is lit and other circuits are on standby. After the water dispenser is filled with water, press the key K3 and the circuit starts to work. The pin 2 of IC1 outputs a high level, so that the transistor VT2 is turned on, the relay JZ1 is pulled in, the heater is energized to start heating, and the pin 1 of the ICl is controlled. The heater is grounded to keep it in contact. At the same time, pin 10 of ICl is low level, and the heating indicator LED-J is on; pin 13 of IC1 is turned to high level, driving VT3 is turned on, and buzzer BE1 makes a sound. When the water boils, the temperature controller trips, IQ pin 1 goes high 9 pin 2 goes low, VT2 turns off, JZ1 is released, and the heater stops heating. At the same time, pins 10 and 8 of IC1 output a high level, the heating indicator LED-J is turned off, and the holding indicator LED-B is lit, indicating that the holding state is entered.

The reboiling procedure of the water dispenser is the same as heating. When the reboil switch K1 is pressed, the pin 6 of IC1 is switched to the high level when it is connected to the trigger signal. The internal timing of IC1 starts, the pin 2 goes high, and the boiling process starts running (the time is about 1 min).

When the timing function needs to be started, the switch K2 is pressed, and the timing time has three time periods of 2h, 4h, and 6h, respectively. When the timing time has not been reached, the corresponding timing indicator (such as LED-4) lights up. Once the internal timing is reached, the power is automatically turned off.

In the fields of industrial control and instrumentation, LEDs are also widely used as indicator lights and operating status indicators. LED indicates the earliest application time, the application circuit is relatively simple, safe and reliable, and will still be a non-negligible field for future LED applications.

Figure 1 Jiale Shi GD929B computer type dual temperature mini water dispenser circuit