Touch light switch delay circuit
Posted on Nov 10, 2015 8221
Is a good touch-down can delay the lamp, the circuit is characterized by: the static power consumption minimal; External switch terminal
is only resistant to root, you can directly replace the ordinary switch, figure A novel precision voltage regulator integrated circuit T1.43 } or AS431, image only dressed leather outer seal pole tube, with the female usually the anode electrode between the non-conducting thyristor VT1 Ge broken pipe, lamp F does not shine. When a finger touches the body M when the leakage current flowing through R. , R. Partial pressure, was added to F1,431 control electrode so that T L131 quickly turned, 20V DC through R ,, TI.43l and VD6 to C. Charging wells by R, muddy base VT2 eight poles, so that VT2 conduction, VT1 trigger current that is obtained while the opening of the lamp E on energized to emit light. After eight hand from M, Ct stored charge through R: v r2 to discharge, deceased mother maintain VT2 remain turned on, the lamp E will not be extinguished. Until C- discharge current decreases, sufficient to maintain when conducting VT2, VT1 trigger the loss of current when the AC zero crossing, namely Ge broken lamp E goes out. Mainly by the delay time of the circuit G, R. Q. constant discharge decision. In addition, the trigger sensitivity of VT1 and VT2 magnification p value of Q has a great influence on the delay. VT1 best Mitsubishi CR2AM-12 or CR3AS-12 micro-triggered thyristor way, as long as they have a touch shake 0_irnA current that can turn by the Secretary; VT2 should adopt Samsung TIP50 or MPSA-14 type _ = diode, requiring p / 50, when asked about the delay peel 70s around; the p 250, R. Selection of 4 7Mn H ten, uh delay time reaches 5m, n about.