It’s a Farnell Instruments L Since you are charging the inductor 40, times per second, you are producing only 1. The disadvantage of course is a more complex circuit. Use of the information on this site may require a license from a third party, or a license from TI. We don’t really know without seeing his schematic, but if it uses the current sense option to regulate the load current that leaves the 1. By providing technical information, TI does not intend to offer or provide engineering services or advice concerning Customer’s design.

Uploader: Barr
Date Added: 16 December 2018
File Size: 10.42 Mb
Operating Systems: Windows NT/2000/XP/2003/2003/7/8/10 MacOS 10/X
Downloads: 21692
Price: Free* [*Free Regsitration Required]

That Vcc capacitor needs to be mc34063 led between the Vcc and ground pins of the IC. And I was just joking! Btw, that circuit is constant voltage, its not suitable for driving led which needs constant current. This site uses cookies to deliver our mc3406 and to show you relevant ads and job listings. Feedback Control This circuit promises greater accuracy, if that is a requirement, as well mc34063 led more flexibility in choosing the current setting sense resistor value.

You are likely bumping up against mc34063 led current limit. Here mc34063 led one way to delay powering the sections that draw the larger current, allowing the unit to boot up before powering the final load.

My benchtop power supply has oed maximum current limit of 2A.

April 22, Once the Input voltage goes under 1. The article suggests mc34063 led a soft start measure to fix this. Mar 1, mc34063 led Maybe start off by changing the voltage to 3V which should be safe for the led and see how the converter works.

The switch operates on a fixed duty cycle of about 6: Inductor is a uH. Maybe the current does not actually flow through mc34063 led current sensor? Oct 18, 1. Do you have another question? Try to put npn at the output so that 0. Unless you mean the duty cycle of the output switch rather than the capacitor.

MC Help – Page 1

I can understand why this is occurring on a very rough basis: On power up this will pull the input pin to VCC wich is higher then mc34063 led.

Oct 19, mc34063 led. The current increases at the same rate but has a different starting point. Should this be possible?

Dimming a 3W led using mc34063

Another advantage mc34063 led that the power loss in the sense resistor can be reduced for both heating and power efficiency gains in higher power applications.

Also, the efficiency seems to be poor mc34063 led to get 70mA out I am measuring about the same mc3063 the input – surely it should be less?

Mmc34063 will need to be taken when high gains are used, as interference and noise will be amplified. I would normally suggest using mc34063 led buck converter setup with the LED and current sense resistor as the load and feedback point.

Mc34063 led to Power Management. OR is there another way you could dim the LED? During start-up, the duty cycles will be higher and this can cause all manner of problems; one way to control the start-up into a heavy load is to step the operating frequency low frequency permits a longer turn-on time for an effectively longer duty cycle. The MC will limit current when the voltage across the Vcc-Ipk pins reaches mc34063 led value between 0. A new LED may draw more current mc34063 led the voltage you are want.

Oct 23, At low currents i. I am assuming you don’t have a 0.