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connect them serialy ,applay 380 VDC to anode and switch them on via Nmosfet.
Each Led has a voltage drop which is from 1.2 - 2.4 vdc.If you connect them in serie you need to apply 200x1.2 (or 2.4) depending on the type of the led.Such a voltage you can controll with the NMOS-fet applayinf a voltage of 5V if you use the L type pf the mos-fet. As the precaution you can put the resistor in serie with the led diodes.You can lower the voltage if you use 8 bits ( or complete port ). Than you have to devide them in groups of 25 apply the voltage 25x1.2 (or 2.4 ) to zthe anode of first diode in serie and connect the drain of the mos-fet to the catode of the last diode in serie. Controll the gate of the mos-fet from the controller and conect the resistor of 100 - 1K in serie with the gate.Connect the resistor of few K from the gate to GND at wich is connected the source of the mos-fet.
Hi,
Do you want to control each individually? or all together?
If you want to drive each individual, I think some sort of serial interface is the best. Something SPI-like.
If your request is literal, that you want to power 200 leds from an 8 bit port without external power, I don't think that is practical.
Connect 100 diodes in series in one direction, then connect 100 diodes in series in the opposite direction ..
Connect both chains front-to-back in parallel and add ≈2.2µF/250Vac capacitor in series with diodes .. The role of the cap is to add some non-heating resistance so diodes are not exposed to full 220Vac but to <200Vac (100*2V) ..
Youy can use a relay or triac to switch this circuit on and off ..
See pictures below on how to can control this diodes-cap circuit of 220Vac from single microcontroller pin ..
Regards,
IanP
how many leds i can put in simple cirucit with PIC , when i use PC supply . In momemnt i use the circuit on diagram , but i wanna put more led, and what transistor mus use
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