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Help with smart twilight switch design LTSPICE


New Member
The main specification consists in the resolution of a technical problem by the use of electronic systems
It is proposed to design an Adaptive flashlight so that the light intensity depends on the brightness environmental. When there is a lot of ambient light the flashlight is off and according to the light
it decreases in intensity, the light emitted is increasing. When there is no light ambient, it will illuminate with full power (10 W). The system musthave a light sensor visible, a conditioning circuit, a modulation control circuit of Pulse width (PWM), a power circuit and a 10 W LED. The voltage of Flashlight input is between 12 V and 15 V. The LED is 10 V with a maximum current of 1 A.
So I have to use in it the schematic LDR (BPW21), for PWM the SG3524 or NE555. I cannot use Potentiometer, I have to use Voltage Source


Well-Known Member
Most Helpful Member
Welcome to ETO!
As this is 'Homework Help', not 'Homework done for you', you are expected to post your best effort at a solution. Can you post your schematic?


New Member
I was mixing several ideas of exercises that I had done. I'm mixing a class D power amplifier (designed for audio) with a transimpedance amplifier . I am taking a current source as the photodiode, entering at the 2nd 555 to control the pulse modulation. But I am sure there is an easy way to develop it. Teacher recommends use the SG3524. A power circuit remains, which maybe should have a capacitor for an stability on the LED.
I post the schematic on LTSpice and the library used.
Thanks in advance


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