21,589 reputation
12361
bio website n/a
location Toronto, Canada
age 40
visits member for 4 years
seen 36 mins ago

c programmer, embedded dabbler, power supply tinkerer. (also loser of three consecutive moderator elections on EE.SE.)

[formerly known as 'madmanguruman' but shed that identity after a nice conversation with Olin Lathrop at Microchip MASTERS 2014.]

almost 15 years experience with switching power supplies at two different companies in the greater toronto area. worked my way from production technician to sustaining engineering, then product development (electrical and embedded). also fluent in vba and labview. currently studying project management theory while working as a power supply designer.


28m
comment How to improve current control loop in power supply?
Did you look at the output current with a current probe when regulating in CC mode? Looking at the voltage isn't entirely fair since the voltage loop is doing nothing at that point. What are you using as a load? (An active load has its own loop and can end up fighting with the PS loop, making a steady load look dynamic. Use resistors if possible)
2d
answered SMPS: What is current mode instability (aka “sub-harmonic oscillation”)?
Oct
20
revised What happens when a MOSFETs gate is left open?
title fix
Oct
17
comment Very intermittent power MOSFET failure
Further to the question - if I'm looking for a fault which I cannot replicate, and I find some 'badness' in there that makes me scratch my head, I would do what I could to fix that badness even if the root cause remains elusive. It sucks, but sometimes a rare, corner-case issue has to be fixed empirically, by making improvements and seeing if the failure rate over time and quantity improves.
Oct
17
revised Very intermittent power MOSFET failure
"don't fry me" is an invitation to get fried.
Oct
17
comment Very intermittent power MOSFET failure
Welcome to EE.SE. All in all, this is a pretty good first question. +1 from me.
Oct
17
revised Very intermittent power MOSFET failure
deleted 48 characters in body
Oct
15
comment How to make a 40mH inductor
What is the nature of the signal that the inductor will be carrying? What's the frequency of the signal? It's impossible to design an inductor without knowing more about the application.
Oct
15
comment What is the difference between debug mode and normal execution on dspic?
Without more details this is likely impossible to answer. A good place to start would be sharing your code.
Oct
14
awarded  Nice Question
Oct
3
comment Where can I learn Switched Mode Power Supply Design?
Also, your question title is about learning SMPS design, and the body of your question is asking specific design questions (which are more appropriate for this site). Choose one or the other please.
Oct
3
comment Where can I learn Switched Mode Power Supply Design?
This question is impossibly broad. There are curricula dedicated to power electronics and power conversion in universities worldwide, hundreds of books on the market and hundreds of approaches to "how do I convert X into Y?". Start with a book that teaches the fundamentals of power conversion, and once you get the basics down, analyze one of those 'poor' DC/DC boards and figure out why it's poor before designing a replacement. After all, without the right knowledge, are you a competent judge of why your chosen DC/DC converters are poor?
Oct
2
comment Boost Converter Efficiency goes down as Duty Cycle goes up?
Hint: What happens to V as D increases? What happens to the MOSFET switch current as D increases?
Oct
2
answered Which files to version control in mplabx nbproject directory?
Oct
1
awarded  Explainer
Sep
30
revised Is this Half-Bridge waveform right?
added 269 characters in body
Sep
30
answered Is this Half-Bridge waveform right?
Sep
30
comment Is this Half-Bridge waveform right?
There's no path to discharge the gate other than the resistor, which will take much longer than your total off-time to achieve. You need active pull-down.
Sep
30
comment Is this Half-Bridge waveform right?
Your circuit is AC-coupling the waveform into a 'DC-restore' gate drive circuit. The gate connection should be at the other side of D2 (minus the 100nF cap) and of course you will need a PNP transistor for fast turn-off.
Sep
30
comment Is this Half-Bridge waveform right?
That figure should work fine (conceptually) - obviously its missing some components but driving the FETs like that is valid IMHO.