No National LM samples. I compute about a watt when the average inductor current is 2A. Sorry, i am really zero knowledge of this, and i dont know where to start learning. This is almost twice what the data sheet shows. We can, for one thing, calculate actual power in the output transistor during the full switching cycle and go from there. New chip from National LM Wow, very interesting. I will say this.

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Not sure yet of the connections, but yes i think it might be able to drive the 5w LS. Let us know how you make out with the new chip if you can.

That would occur at different Vin depending on if you drove a single LS at.

That said, the average inductor current for the LM or LM happens to be the same DC current flowing from the battery. Learn how your comment data is processed.

V to 5V Step Up DC-DC Converter – Electronics-Lab

What are the lm26623 needed for this purpose? Thanks for the info! Sorry, i am really zero knowledge of this, and i dont know where to start learning.


Looks very similar to the LM What are the exact dimensions of the pcb drawn in this page. Flashlights and Parts WTS: Then, R3 can be selected using Equation 1. If you have a scope, maybe you could measure Vds and calculate the oed Rds and that would be just as simple.

Conclusive tests would be done with a scope and current probe. As for C5 you can use a through hole capacitor that will be fitted lm26223 the PCB.

2.4V to 5V Step Up DC-DC Converter

Can i use this inductor? This means a slightly different inductor design which will eat more efficiency.

This draws ma at over 6 volts, which is pretty high. Connect Vdd to a separate voltage source, such as three batteries in series, or better yet: If not, perhaps using an LS simulator in series with one real LS might work good too. Leaving it on at say 7 volts might bother the chip when the power source is switched off. PCB dimensions are I sampled 5 of each.

This is exactly what the circuit needs. I get some extrapolated ideas of what the IC can do by overdriving a single LS. Im betting that the extra voltage eats more efficiency too, however that extra voltage, being bootstrapped, might drive the Mosfet more efficiently.


New chip from National LM

Midpoint on the time axis of the ‘on’ part of the waveform 3. To make things easier I think I’ll start a web page with my scope pictures and such. Keep in mind that the voltage should be inside the input limits.

From there we can determine if this chip lmm2623 fly with the 5w LS or not. All references are to the eval board which has VDD bootstrapped to the output. Since the Boot power pin is specified from 2.

Thanks 2 years ago. All times are GMT New chip from National LM MrAl, I reference it in formula since ler really depends on how many watts you are trying to drive to the load.