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Title: HID Electronic Ballast Dimming Post by: SANEMB on November 20, 2009, 09:42:54 09:42 Hi Guys,
I have freezed out the design for 250W HID Electronic Ballast for HID Lamps ( MH/HPS Lamps). So now I want to have dimming functionality in the above design. How it can be achieved. Can anyone help me on this. Title: Re: HID Electronic Ballast Dimming Post by: solutions on November 21, 2009, 09:22:36 09:22 PWM
Title: Re: HID Electronic Ballast Dimming Post by: SANEMB on November 21, 2009, 10:46:57 10:46 HID Ballast design topology consists
a. EMI Filter b. Bridge Rectifier c. Boost PFC Stage d. Buck Stage e. Full Bridge o/p Stage f. Ignition Stage Now where I need to use the PWM for Dimming and How it can be done. Title: Re: HID Electronic Ballast Dimming Post by: j0k3r on November 22, 2009, 10:40:40 10:40 Perhaps on your Full Bridge o/p Stage.
But is a dark shoot, without the schematic, or more details. If you give more details, maybe we can help more. Like "Solutions" says the pwm is the best thing. Title: Re: HID Electronic Ballast Dimming Post by: solutions on November 23, 2009, 06:32:53 06:32 Agree.
Either that or in the buck stage, as the switcher is already there, though the control loop for the buck could be a problem if PWM dim was not contemplated...again, agree.... we need to see the schematic. Title: Re: HID Electronic Ballast Dimming Post by: abcsantosh on November 23, 2009, 12:42:12 12:42 Hi look for microchip application note AN809. It explains the basic theory for ballast dimming.
Digitally Addressable DALI Dimming Ballast App http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011968 or look here http://www.irf.com/technical-info/refdesigns/lightingkits.html Title: Re: HID Electronic Ballast Dimming Post by: tAhm1D on November 23, 2009, 05:47:41 17:47 Hi,
If you post the schematic, it will not be difficult to help you. |