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Which is the cheapest constant current LED driver with decently good power factor for home lighting application for 250V AC? 1 2015-07-10 12:04:58.6
Hi Does ON Semi still make KAF-1603-12-5-A-EVK eval kits? I went through everyone of your sales offices and non of then even show it. Thanks 65 2015-06-08 13:33:09.166
The NCL30060B1DR2G can't buy in the market, I would like to ask in the website can buy? 220 2015-03-26 10:18:59.049
I want to evaluate CMOS image sensor NOIM1SM9600A-D, but don't see an eval board for it. I am also interested in CCD sensor KAF-1603-D (which says the eval board is KEK-4H0078-KAF-1602/1603-12-5 in the datasheet), but I don't see that in the list of eval boards on your website. Can you please advise? 231 2015-03-25 09:31:21.949
Dear engineer, The NCL30060 includes brown out protection providing A defined shutdown for low input voltage.typically 111 V. if the input voltage is lower than this value The NCL30060 will enter the brown out protection mode, which will not be started? 234 2015-03-25 09:30:24.672
Hello, engineer, I would like to ask about NCL30060 can be used in 38-55VAC input environment?If not, the minimum input voltage should be? 233 2015-03-24 02:50:51.426
I need to make a light for a showroom - the idea is to have about 20 or so small led light bulbs each one at the end of a 4 meter cable, but all coming from one central hub - can anyone advise ? My technical knowledge arrives to the level of turning on a light switch , ie ZERO !! 558 2015-01-20 11:49:29.588
Good day ! Our customers after consideration of the product: http://www.onsemi.ru.com/pub_link/Collateral/NSI50350AD-D.PDF Have the same question: why curent error 10% it is very big ! Requirements of Russian standards for lighting equipment no more than 5%. ONs can explain how to set the current with better accuracy with NSIxxx family ? 470 2015-01-16 09:55:08.175
I am trying to power a single led bulb, that will be inside one side of a geode. I would like to have the option to make it red, green , blue or various shades of each and also be able to make it one color or another. How do I drive that? 551 2015-01-05 15:13:40.025
I wonder if you have any power supply design switched to power leds 300W. Since I am using only 01 led 300W, I need a power supply with constant current, 33V x 9A. To have some solutions, but they are not components of ON. If you can help me I thank you. Regards, Barone. 575 2015-01-05 14:42:28.23
I've been chasing up some 10 or 20 W LED lights for blast freezers. The temperature range is -40 deg C to +40 deg C. is there anyone making LED drivers that will operate the low temp range. Most I find only rate down to -10 or -20 deg C. I know the LED Chips can handle the temperature range. It would be nice to have an all in one unit but failing that we may have to mount the driver externally. 589 2014-11-26 07:54:17.787
I have a need for a constant current driver like the NSI45030AT1G, but need 40MA device. Need is about 500 per month. Is such a device in the pipeline? 539 2014-11-24 14:14:59.092
We are an OEM lighting fixture manufacturer, we do not manufacture LED drivers. The question is when do you see driver efficiencies getting better than 90 percent? Our clients are lighting people used to fluorescent and HID systems with efficiencies of better than 95 percent and they are constantly dismayed to have us explain that the best efficiencies we see on drivers is about 87 percent, with a range of 77 to 85 percent being more typical. Barry Besmanoff, Litelab Corporation 824 2014-09-11 11:18:11.471
Dear Expert, i want to design a lamp for manufacturing, i want an advice about a simple but efficient design. what kind of circuit, led chip and driver, to produce a lamp equivalent to a 100 watts incandescent lamp runs on the European AC voltage. 928 2014-08-18 12:43:48.624
Dear Gentleman. My name is Silvio Hideo Ishizawa. I'm planning to use component NSIC2050JB to drive 30 LEDs (LSE6SF from Osram). With simulation from ON site using AC line with 100V to 130V it is require just 30 LEDs and one resistor of 1.0mOhm. However I need to have these LED supplied with full AC range (100V to 240V). I would like receive suggestions to have these LEDs supplied with 100V to 240V automaticly. I'm looking forward receive your attention. Thank you. Silvio Hideo Ishizawa 875 2014-08-08 06:35:03.823
Sir, i want to make 5 nos.(1 watt 350ma)led bulb at 230 volt ac without transformer what have i to do? 949 2014-07-24 14:25:41.356
Hello Team, I need to design 3 drivers types: TYPE I: 1) Input voltage (VAC): 110-240; 2) Power rating (W): 20w; 3) Output current (mA): 320 mA; 4) Output voltage(V): 36-60 Vdc; 5) PFC / iTHD: >90% / <10%; TYPE II: 1) Input voltage (VAC): 110-240; 2) Power rating (W): 50w; 3) Output current (mA): 840 mA; 4) Output voltage(V): 36-60 Vdc; 5) PFC / iTHD: >90% / <10%; Type III: this for outdoor application like Street Light: 1) Power rating (W): 70w; 2) Output current (mA): 1.4 A; 3) Input voltage (VAC): 110-308 4) PFC / iTHD: >90% / <10% Please tell me how I can to start the design, what are your suggestions, Waiting your comments 1008 2014-07-03 08:52:24.737
design High Side Low Side for CCR 989 2014-06-25 13:42:34.534
I am looking at the NSI45060 device and would like to know what the formula is for calculating Radj. Where can I purchase an EVM for this product? 1261 2014-02-07 09:22:38.094
Hello, I am Marco Porzio and I am looking for an high-side driver. I think to use your NCV7608. My preference is for the SSOP-36 EP package (NCV7608DQ), but I did not find any information about the connection of the pad shown in the "Package dimension" section on the datasheet. Is it only a thermal pad or it need a connection (maybe at GND or Vs)? I suppose that it is a thermal pad (no logical connection needed) but I can not find any confirm to that. Thanks in advance. 1361 2013-12-17 12:51:25.796
We want output with constant color lighting with 230 vac to convert 3 watt ,6 w,10w ,12 w and 15 watt. suggest led driver from your product. 1417 2013-10-25 08:30:00.877
Dear sir ,can we use HB of ncp1397 to short to ground for others applications? thanks. 1495 2013-09-26 09:15:11.299
Dear Expert I want to flashing a series of LEDs. how can i do it, as led require 3.5v/25mA current. kindly guide me. 1548 2013-09-06 16:05:00.817
How can I create a thin battery operated LED light, so when I put pressure on a certain area the light will light? For example my son wants the monkey bars to light up when he grabs each one and squeezes them. I'm trying to figure out how to do that. Any ideas... 1583 2013-08-19 15:22:23.741
This is with respect to the Application note DN05047/D. It says in the circuit operation section that the output of the bridge rectifier is half sine wave, which incorrect. Also the circuit uses NSIC2030B ccr which is rated for 30 mA. Since the power rating of this design is 15 Watts, the LED current must be more than that ( around 5 0 mA). Kindly clarify. 1448 2013-07-16 23:59:15.57
Will the NCL30160 work properly ift there is only a single configuration of inductor and ROT-Resistor for various LED loads (1-8 LEDs). What are the main disadvantages then? Efficiency reduction? 1736 2013-05-29 13:54:35.44
I'd like to design a LED driver from AC mains (230 Volt / 50Hz) and DC (160V - 260V). I'm looking for a single stage PSR PFC solution that generates 28V on the secondary side. Those 28V should supply a flexible LED string (1 - 8) LED @350mA. I'm thinking about NCL30160 to do the LED control capacitorless. On secondary side there is also a uC to supervise LED string current and voltage. Do you have an idea which IC can do the single stage PSR PFC? Best regards 1919 2013-05-22 10:00:08.684
I am technical staff in facilities services for a major university in Texas and would be an end user of LED lighting. I'm also involved with developing Construction Standards for lighting. As there are performance test standards for LED lights such at LM79, TM21, etc., I've not been able to find a performance standard for the driver. Is there one being developed that could eventually be referenced to. I have some basic performance information about drivers, but it would be convenient to use one that industry is adopting. 1840 2013-04-03 16:45:10.119
I am looking for a mass produced driver (chip) to drive 8-10 LEDs back and forth i.e - OOOOOOOOO\n ; ---------------- ; 1870 2013-02-27 09:37:39.92
I have new project, just started. It is a 3-colour 32 x 40 LED display. It will be driven by a small SBC running some custom hardware. It’s at an early stage, but the scheme that I’ve arrived at comprises:\n- 8x8 RGB matrix displays, 20-off per unit: YHT-2388SRGBA by Shenzen Yuhong or YSM-2388CRGBC by China Young Sun LED. 8x8 tile size is about 60 x 60mm.\n- TI TLC5940 16-channel LED driver, 6 off per unit driving 96 rows (3 colours x 32 rows), running from 5V\n- P-channel column drive transistors, 40 off, decoded 1 of 40 from 6 bits using 3 x 74xx154.\nThis arrangement results in control over the matrix in 14 lines.\nIf there were any other schemes that you could suggest, I’d be very pleased to consider them. In particular:\n- alternatives to the TI drivers, matching the TI part’s rather good level of control and perhaps bettering it’s maximum drive current (60-120mA maximum constant current, depending on Vcc)\n- alternatives to the 8x8x3 display tiles\n- a multiple, eg octal, topside driver (P-channel/PNP) rather than singles or duals (a dual, eg IRF7316, was the best I could could find in sub- 0.1R on-resistance).\nMany thanks for your help.\nMark\nMark Leese\nTimos Designs\nScotland, UK\n(+44) 141 586 7093 2332 2012-11-01 13:30:36.0
i am looking for a LED driver IC which can operate on a single Li-Fe 3.2volt battery to drive single 1 watt or 3watt LED 2011 2012-10-23 12:47:50.0
I'm looking for circuits that regulation total power dissipation as an LED warms. That is, the current is adjusted to compensate for forward voltage drop changes with temperature such that E*I is maintained at a nominal level as determined by a voltage input. Also, there is to be 100% duty cycle at a chosen output level.\nI found such a circuit at http://www.maximintegrated.com/app-note ... vp/id/4470 1667 2012-10-18 19:19:42.0
Need a LED Engine designer for Street Lights 2407 2012-10-14 14:45:10.0
I am looking to create an AC LED circuit that accepts both 120-277VAC and is engineered for cost. I've seen designs using an IC and/or a bridge circuit, but none of these have universal voltage acceptance. I am flexible with the # of LEDs used and total power consumption. 2272 2012-09-19 15:01:47.0
Flicker from LED lighting has become a health concern, particularly those frequencies that are not easily noticed but which are still biologically active - eg 100 Hz or 120 Hz . With the long lifetime of LED lamps we risk designing in problems for years to come. Are driver manufacturers taking this issue seriously? 1996 2012-09-18 21:23:26.0
Dear Expert,\n\nI believed in using external driver than a built-in for powering LED lamp.\nPlease advise on how to size up an external constant driver/PSU driving 10pcs of 3W 12V LED lamp connected in parallel.\nForwarding current is 350mA each.\n\nYour prompt respond is highly appreciated.\nThank you\n\nBRegards,\nTomi Goh 1919 2012-08-14 05:07:52.0
Sujest Led Driver step down for single white led. Vin 3.8 to 6.0 DC, I out regulated @ 1.2Amps, eff. 90 percent , High frequency for small size circuit, enable function needed. US High volume production Flashlight. Thank you 2012 2012-07-31 15:41:02.0
I need to control the power dissipated by groups of LEDs up to 600mA. As you know, when LEDs heat up, the forward voltage drop decreases resulting in reduced emission, so controlling current is not sufficient to controlling the total power emitted. Got any circuit devices for that? 1926 2012-07-31 14:42:16.0
In what way can I determine if a LED will operate best on a constant current or a constant voltage driver? 2009 2012-07-31 14:37:22.0
Hi, my name is Paulo Cesar. I am an electrical engineer, and I'm studying drivers for LEDs. I wonder what the importance of a driver for power on the order of 100W offer electrical insulation? I thank you for your attention. 1907 2012-06-26 14:26:51.0
What kind of light can I use for hospital indoor apart from fluorescent 1971 2012-05-30 21:41:30.0
Are any of your switching regulators/controllers rated for -55 deg C operation? 1975 2012-05-30 16:48:59.0
Please advise how we can obtain:\n\nFigure 10. Is NCP1529 Torch Application Demonstration Board 2078 2012-05-30 15:54:49.0
We are using a NCP1605 for PFC and Pre- regulator in 95W PSU driving 30 x 3W RGB LEDs. Works OK on 230V. Works OK on 120V when ambient temp is low. However when local ambient exceeds 80 Deg C the NCP1605 starts to shut down, and Pre-regulation becomes erratic. Data sheet states this IC is OK up to 100 Deg C. Are there any problems or changes in characteristics that occur above 80 Deg C? 1813 2012-05-01 13:30:21.0
I need to linearly modulate High-Power LEDs with analog signals (sine, triangle wave) within a 1Hz-500Khz frequency range. The driver must also current-limit the LEDs. What Onsemi circuit topology do you have that will accomplish this??? 2062 2012-04-30 15:52:59.0
Hi, I cannot download any of the documents! EHY? Tamás\nhttp://c.thinkonsemi.com/topic/serv/6HE ... html/intro 1728 2012-04-18 08:40:12.0
How do I select the resistor value on the NS145090JDT4G\nfor a specific current through LEDs? 2236 2012-04-12 16:58:29.0
When will you have a low cost (under $1.00) driver to power (350 mil amps - 1,5 amps) a Individual LED from a 12v source? And preferably with all the perks. (current protection, dimming etc.)??????????\n\nUltimately this way I can custom create my products with 1 to 1,000's of LED's with out changing up drivers again and again. I notice the flash light market has them but the supply voltage and form factor doesn't help me. 1913 2012-03-28 15:57:27.0
Hi! I am designing a LED project and cannot come with a circuit for it. Maybe the experts here can help me out. I want to drive between 10-20 smd LEDs (1206 package, no high power nor high brightness) using as few components as possible. I want to use a low pint count microcontroller to make different patterns with the leds, and use CR2032 coin cell batteries. I really need to make this as small as possible, for example to be able to embed it a piece of paper the size of a credit car. The thing is that I cannot figure out the way to connect that quantity of LEDs for the CR2032 to be able to power them,and all the ICs (which must not be very much, 2-3 ICs). Maybe someone could point out any suggestiong for a way to boost the power of the CR2032 battery (or two batteries max if necessary) and the best way to connect the LEDs (in matrix, in rows, multiplixed). Thanks for your help and suggestions. 2634 2012-03-10 16:16:49.0
I want 10watts to 100 watts PFC coreection and CC LED driver and also 12V supply to run a FAn of @ 250 ma for cooling : Pl suggest suitable device or reference design 2049 2012-03-10 09:52:09.0
Dear Sir,\nWe are manufacturer and supplier to the end user of solar LED lighting . We need to standardized our LED light for 55lumen/watt. to achieve this result we need high lumen LED for submit the LED bulb to the relevant authority. Please inform us from where we can get such high lumen LED for our LED light standardized.\nThanks ; Regard,\nMohammed Humayun Kabir Khan\nR;D officer, Limso Foundation, Bangladesh. 1922 2012-03-09 15:53:55.0
We are LED light maker and supplier to the remote village end user. We need to be standardized our LED lamp as it should be minimum 55 lumen per watt.Our local market LED bulb can deliver only 12 lumen per watt. Please let us know the sources of high lumen LED to design a LED bulb which can deliver 55 to 60 lumen per watt. Thanks ; Regards,\nMohammed Humayun Kabir Khan\nFriday 02 March 2012\nEmail: mdhumayunkabirkhan@yahoo.com 1832 2012-03-02 11:44:16.0
I am designing a system that is PWM dimmable (via uC), 100W+, Offline (120VAC). Looked at ncl30001, but don't want to use electrolytic caps due to their limited life span. What would be the best driver for the job? 1982 2012-03-02 00:37:03.0
Could you suggest a circut to drive 72 led at 100mA using CCR (NSIC50xx) family (non isolated) which can be driven on 230V AC. There are not any reference for 230Vac driven CCR circuit. Even your latest design note DN05021 / DN05022 does not specify how to drive at 230V AC. Also datasheet for NSIC5020 is missing.\n\nHemant Savla 1993 2012-03-01 05:24:46.0
Do you make drivers for LED 4' Tubes? 2224 2012-02-29 18:50:33.0
In what application note do you provide the circuit of the ;Power Factor Corrected TRIAC Dimmable LED Driver Solution; presented in the video? 1880 2012-02-29 16:27:28.0
Hi, do you have a hb led driver with open and short circuit detection?\nThe current must be 1A. 2018 2012-02-29 15:55:32.0
We are looking to build a 40watt LED assembly using 660 chips, non dimmable with a supply of 480vAC 60Hz. Preferably no electrolytic caps. Advise please. 1712 2012-02-29 15:14:39.0
I want to drive a osram GD+ led with 4volt and 6 volt Lead Acid battery for flashlight.Suggest me circuit with very low component count. 1942 2012-02-05 17:33:33.0
CAN WE DIN HIGH POWER LED LOADSOVER 5 TO 20 MIN. 2235 2012-01-26 20:29:10.0
I need to drive one white LED with regulated current at 1 of 3 microcontroller-selectable levels: 10, 90 or 800 mA. Input may be as low as 2.4V. The closest we've come is starting with a T.I. TPS63000 and then adding ckty to sense current and apply voltage representing it to the feedback pin of that regulator. Would like to find a more integrated and lower cost solution. 2246 2012-01-26 15:46:54.0
Why not constant voltage with tiny voltage fluctuation to drive LEDs in series instead of constant current? 1913 2012-01-21 14:18:41.0
could you introduce some IC which can drive LED. input 8-12V and out 9A @3.5v... 2491 2011-12-29 05:03:28.0
Designing a LED fixture with LV AC input. The LED picked is 350ma 3.5V. There is a specification for high efficiency (;90%), minimum EMI, PF minimum of 0.7 (on any intensity), unit is to be dimmed for Medium intensity of 30% and Low to 10% by internal sensing of input (not linear dimming, example: input decrease 83% to produce 30% LED intensity and decrease to 72% input for 10% intensity), to be used in ambient temp of -40C to +55C. Need a recommended driver. 1943 2011-12-21 22:29:07.0
Does LED drivers have to be isolated? 2114 2011-12-21 18:33:16.0
Hello,\nI like to sailboat and wants to change incandescent sailboat lights for LED ones. Consider that at night you will be using lights and the battery will be falling down. In this case, which will be the best LED driver topology in order to maintant an acceptable lighting level. I mean, which topology gives you for more time the CC current need it by your LEDs.\nthank you\n\nMarcelo 2115 2011-12-05 01:48:12.0
Pulsed current LED driver IC with duty cycle control ; digital or analouge dimming facility 1935 2011-11-18 08:03:59.0
Does On semi has reference cct design for 90 - 260Vac input to produce constant current output of 350mA and 500mA at 3 max Vdc, i.e. 120V for 36 LED, 80 V for 24 LED and 40V for 12 LED conected in series. \nPlease specify your On semiconductor that meets these 3 applications.\nWe need to use immediately and please response and we can discuss over phone if necessary.\nThanks\nJohn L. 1898 2011-11-07 19:22:39.0
On the MC34063 there are plenty of design links out there, for example this one - http://dics.voicecontrol.ro/tutorials/mc34063/ which is a link to a handy design calculator. You type in what you need and it calculates the values for you. We have reviewed the data sheet for the NCV33163 and we believe we have the values for our design which is 12 vdc in and we need 49-51 vdc out at 2 amps. Is there a calculator anywhere we can use to verify our design? Or can one of the experts run through the calculations and post what they believe would be good starting points for the design? 1737 2011-11-07 15:59:09.0
We really like the MC34063, but we are working with some new parts that require 46-48 VDC. Is there a higher voltage out version of this part? 1744 2011-11-03 17:34:07.0
Where can I find application/design notes for the CAT4101? 1931 2011-10-04 02:15:58.0
I want to design 3W,5W,12W LED driver.But I do not know how to design? I dont basic of LED Design. 2131 2011-09-30 12:48:04.0
How to improve the power factor about the device ncl30001?What's the matter with my ncl30001,Pf=0.7,when vin=220VAC? 2010 2011-09-30 01:02:44.0
I want to understand when isolation is required in LED lighting driver applications. I understand that Underwriters Laboratories (UL) has standards for safety certification that sometimes require isolation and sometimes do not, but I do not understand when it is required and when it is not.\n\nPreviously I had believed that isolation is always required when designing a driver that powers an LED from an AC mains voltage (off-line application). And I had understood that flyback transformer designs were used largely because they provide this isolation. However as I read more about the topic it seems there are some off-line applications where isolation is not required.\n\nIs there a wattage or voltage limit that defines when isolation is required? Or does it depend on the type of application? For example, is isolation required by UL when designing a driver that would operate inside a closed mechanical structure such as an LED retrofit light bulb? What if the driver is mechanically separated from the LED element and connected by wires? 1907 2011-09-25 15:23:26.0
I'm exposed pretty well to LED driver but 360 degree LED's, especially the low power consumption of 360 degree LED's. I need some helps on selecting (and names of suppliers) such the low power comsumption series of 360 degree LED's . The 360 degree LED's must operate seemlessly when power switched to Back-up Power supplied from Super Cap(s) for a minimum time of 120 seconds. Thanks for any suggestion/info. 1851 2011-08-23 16:12:40.0
I am building a giant 7 segment display and I would like to use the multiplexed technique without loosing bright ( during the time the 7 segment display digit is off ) which is the best solution ? thanks a lot 1976 2011-06-23 16:48:37.0
Are you offering CCR LED drivers with thermo-management functionality? Respectively, could you please suggest thermo-management circuitry for CAT4101? 1946 2011-06-02 19:12:57.0
I was wondering if the NSI45020 can be used with PWM dimming frequency 19 kHz. What is the maximum frequency at which it can operate? 2096 2011-05-27 01:06:30.0
PN:NUD4011 Reference Firure 6 of the NUD4011 specification. CKT: Prior to the diode briode bridge, I will have a series impedance (0.44 ufd cap.) on the L1 side of the AC Line, and a 10 ohm MOF resistor on the N side of the line. I will have a cap (small value lytic) at the output of the diode bridge. I plan on using a TVS to limit the max voltage seen by the NUD4011, clamping at 65 volts after the diode bridge. I would like to know if I can connect two strings of LED's (14 LED's in series per string) @ 6 ma current. One LED string would connect to Iout1 with a forward voltage drop of 41 volts dc. The second LED string would connect to Iout2 with a forward voltage drop of 53 volts. This represents the min and max forward voltage drop of the LED's. The goal is to reduce the total voltage seen by How will the NUD4011 respond to the two different voltages on its output? Where should pin 4 be connected? How is the power dissipation calculated? Is it the drop per driver channel for its respective LED string? I plan on using a TVS to limit the max voltage seen by the NUD4011, clamping at 65 volts. Are there any other precautions I should look at? 1824 2011-05-27 00:59:32.0