HT7700 touch-type stepless dimming light circuit

The touch-type five-level state light lamp
is made of the HT7700 dimming special integrated circuit produced by Taiwan's HOI (TEK) company. Through the touch electrode sheet M, the light is continuously illuminated steplessly . In essence, the light is It is a 96-level brightness change.     IIT77. . Manufactured using CML)S process, standard DIP-S package , the functions of each pin are as follows: ① Pin zL:, is the AC zero-crossing signal detection terminal; ② Pin SENSE: K FY, is the touch sensing signal or keying signal input terminal; ③ pin FB, is the input terminal for the signal current when touching ; ④ pin V, the negative terminal of the power supply; ⑤ pin TRIC;, the trigger signal output terminal, used to contact the thyristor; ⑥ and ⑦ pins are OSC2 and OSC1, They are the oscillation signal output and input terminals respectively, and an external 62kfl resistor is connected; ⑧Pin V West is the positive terminal of the IU source. The power supply voltage range used by the HT7700 integrated circuit is 9-12V.     In the figure, VD3, vS, R, and (1) form a resistor step-down rectifier IU circuit, which outputs about 9V DC working voltage for the HT7700. When the power is first connected, the lamp E is in an extinguished state. When the human hand touches the electrode sheet M (You can use the metal shell of the Taiwan Spider). If the touch time is less than 0 7s, the light will change from extinguished to the brightest; continue to touch, and the brightness of the light will decrease smoothly by 96. After you let go, the light will maintain this brightness. Then use If the time is less than 0 7s , touch M. The light E will go out. C is an isolation safety capacitor, and a CBB1000V high-voltage capacitor should be used to ensure the safety of the moon user.