Multifunctional dimming light circuit using application-specific integrated circuit

It is a multi-functional light lamp circuit made of HT7706 special integrated circuit
. It has four different dimming functions: stepless, step dimming, delayed lights-off and cycle automatic lights-off.
    HT7706 is a multi-functional LED-specific integrated circuit
produced by Taiwan's Hetai Company . It is manufactured using CMOS technology and has 16 standard DIP-16 packages . The brief functions of the pins are as follows. Pin ①zC is the AC zero-crossing signal input terminal. Pin ②(JSC,1 is the oscillation input terminal. Pin ③OSC2 is the oscillation output terminal. Pin ④TEST, test terminal, can be left floating in normal times. Pin ⑤Tl, test terminal, can be left floating . Pin ⑥OUT, control signal At the output end, the control signal is added to the gate of the thyristor VTH through the capacitor c2 to control the conduction angle of the thyristor. Pin ⑦60/50 is the AC power frequency selection terminal. When the AC frequency is 60HZ, this pin is left floating; When the AC frequency is 50Hz, this pin is connected to the negative terminal V of the power supply. Pin ⑧¨s is the negative terminal of the power supply. Pin ③PWR is the reset and clearing terminal. Pin ⑩BZ1 and pin ⑩B22 are buzzer output terminals and can be connected externally. A piezoelectric ceramic buzzer piece B. Pin ⑩K1, keying input terminal l, low level trigger is valid, external key switch SB1 is connected. When SB1 is pressed, the light changes from darkest to brightest (or from brightest to brightest) Dark) will change steplessly. Release SB1 and the light brightness will be fixed. When the brightness is adjusted to the darkest or brightest, the light will flash , and at the same time, the buzz output terminals BZ1 and t322 will output signals to cause the external buzz chip to B makes a "beep, beep" sound, indicating that the brightness has withered to the extreme position. After turning on SB1, press SR1 again, the brightness will change . Pin ⑩K2, keying input 2, low level The trigger is valid, and the external key switch SB2 is connected. Press SB2 once, and the brightness changes by one gear, which is divided into 4 gears: off, low light, medium light and strong light. Pin @K3, keying input terminal 3, low level trigger is valid, external Press the button to turn on Terminal 4, low level trigger is valid, external key switch SB4 is connected. Press SL14 once, the light will be on, and after 20min, the light will be off, and after 25min, the light will be on again... In this way, the light E will automatically light up and go out. This mode is used for timing reminders. People, avoid working under the light for a long time, which is beneficial to eyesight protection or other purposes . Pin ⑩V is the positive terminal of the power supply.