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From your note, I understand I have to place a 1meg ohm resistor in series with the three units which are in parallel. That high of a resistance will not let the 1000ma pass will it? Going across a straight 12v, a 1meg resistor will only allow 12micro amps. Maybe I misunderstood the note. Can you clarify?
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From: onhelp@onsemi.com
To: dsdrewyor@comcast.net
Sent: Monday, February 2, 2015 6:14:26 PM
Subject: Ask An Expert Notification
Your question:
I have an LED that has a Fv of 3.3v and up to 1000ma drive requirement. My drive source is a PWM signal at 12vdc up to the 1000ma max. What can I use to limit the drive voltage to the LED while still getting the current I need? I have used dropping resistors in the past, but these would be very large resistors. Thanks Dave
has been answered:
You can use our NSI50350AS LED Driver, Constant Current Regulator, 350 mA, 50 V and connect three of them parallel with 1 m Ohm resistor in series.
This configuration will limit your LED current to 1 Amp.
If you have more questions please visit: AskAnExpert application
Kind regards, ON Semiconductor
347
2015-02-16 10:03:38.18
I have an LED that has a Fv of 3.3v and up to 1000ma drive requirement. My drive source is a PWM signal at 12vdc up to the 1000ma max. What can I use to limit the drive voltage to the LED while still getting the current I need? I have used dropping resistors in the past, but these would be very large resistors. Thanks
Dave
342
2015-02-02 16:14:24.935
Hi, I am looking for Heat Emitting Light Bulbs for heating our Fish Culture Ponds (1 Acres each) in Delhi (India). However, we do not have an electricity connection and have to run all our machines on diesel based power generation. Therefore, I was searching for Battery/Cells operated LED Lights. Please advise on the availability (delivery) in India (Delhi) and the costing.
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2014-09-16 12:34:02.417
I'm looking to use some 1W (3.3-3.7v, 350mA) LEDs for accent lighting on a motorcycle. For versatility, and ease of wiring, my preference would be to combine constant current electronics with each LED, and simply provide nominal 12v (11-14v) to their location, rather than daisy-chaining LEDs from a central driver. Would the NSI50350ADT4G be suitable for this purpose? My primary concerns are heat from the large voltage drop requirement, and keeping the combined LED/driver module as small as possible (limited/no heat-sink space).
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2014-03-11 11:24:59.429
ON Semiconductor does not appear to have direct replacement for the obsolete Fairchild LED Driver, FAN5608DHMP. Is there an ON Semi device that has a similar function and can drive 6 LED's?
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For MURS360T3 75A non repititive current is given for 60Hz,thats 16mA. I want to know how much will be the current for 112 ms . This is the pulse which we apply in our circuit .Is there any graph you can provide us relating to Ifsm?
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Hello,
Can you provide me a PSpice model for the component MBRS3100T3-D ?
Waiting for you response,
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I am looking to simplify my rear combo light design for an automotive application, do you have any solutions that might serve my need?
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Does ON Semiconductor offer Automotive rated and certified products?
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