pier

You asked me " can u get one " U asked me wheather can i get LM10 at my place ? Or can i get the circuit ? If it is the circuit u should help me ? I cant design perfectly. I request u to please send me a schematic of the sensing .

Yes AG I can get them .

hi AG Sorry I was a bit late . Could you send me a small schematic for the comparator . I tried and am not able to design it . Please help me . Thanks Pier Francis

st13005 (to220) is available in my country . how about this ?

Hi AG , Thanks a lot for the suggestion , could You sugest me which transistor would be good to use . Thanks Pier .

i'm sorry i made a mistake , it is for the led's to switch off when the voltage rises above 250 volts ac . Pier

Hi AG Hows this arrangement for the led's to switch when the voltage rise above 250 volts AC . Please tell me if this needs correction ? Pier

yes , but none of the led's have failed yet .

hi AG The brightness varies about twice or thrice in some time .

Hi AG The project is fine now, working and having enough brightness, but for the resistor i put 10k 20watt , it is running cooler now . Thanks for the help . I am making the housing for it now . Thanks Pier .

Hey AG I am going to follow your idea of 70 volt i.e, 20 in series . But i need an arrangement to disable mains when the voltage shoots above 240 or 250 . Some one said that there is some special Ic for this purpose . do u have any arrangement for this ? Thanks Pier

Thanks AG I will do it , But as the total led current is 625mA will transformer withstand ? ( 500mA)

Hi AG Thats a good idea, but will if one led blows off then the entire ckt wont work naa . I thought of another arrangement i.e, individual resistors (smd) . (324 - 3.5 )/25mA = 12.8 k for each led . Please go through this ckt AG and let me know if there is any mistakes . I am new to electronics AG that is why i am asking a lot of doubts .

Hi AG Actually i want to reduce the cost and it is for roof lighting . Is there any other method that i can do because I really want to reduce the cost . the transformer here is very costly and you wont get that correct rating mentioned on it and as you know the indian market . they are stingy and their products are a junk . so i am trying it out to really reduce the cost . please advice me on this . Thanks Pier

Hi AG I found the adapter to be too expensive so i decided for an alternative one . the LED ckt draws only a max of 625mA so i decided for the ckt shown in here . I used a 2 amps bridge and a voltage divider followed by a regulator so what will be the wattage of the resistor to be used for both in the divider ? Thanks Pier

Hi AG As you asked the voltage is regulated . It is a switchig adapter , but i dont know the forward voltage or the continious rating of the led cause there are different brands coming to India and to my surprise some shopkeepers also dosen't know it . They will only be interested to give you the details only if you purchase the devices in a lot ( production ) . All that I know is that it is a white led of 5mm . Is there any website to which I can look into ? Thanks Pier .

Hi AG Is this the way u told me to conect ? If so what should be the value of the resistor ? I guess it is 200 ohms . I am planning of using surface mount devices for this can i use resistors of 1206 package to solve the issue ? Thanks Pier .

are any IC's available for this application ?

Audio guru is right . The led draws a max 0f 30mA . I want to power it from a 6 volt AC - DC adapter . The led's are to be in continious on state and should give very long life . I want to arrange it as a small roof lighting .

i need a circuit to drive 20 white led's of 5mm size . Can anyone help me ?

thanks , i'll try it out .

could i use BC547 & BC557 instead of those transistors in your link u gave me ?

thanks Audio guru

I dont know anything in programming and want to make the RGB project in the site's home page . without learing the actual thing , is there any way to just do it for one time for an intrest . thanks and regards . Pier francis .

My parallel port is not working . some one said that it is blown off and another said try change the mother board . Could you suggest me to check what is the actual problem Regards Pier Francis