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Great mamu. Thanks for sharing.When I looked at the datasheet the other day, I was thinking 1.5K pot and a 1k fixed resistor may push the high end a bit higher than the max 5.5vDid you get it as a sample?
is this the OKL2-T/20-W12P2-C or OKL2-T/20-W12N2-C?
Very nice! Being fairly new to modding, i ordered some of these by "Accident". In my attempts to actually use them, most people have told me i need to get a PCB made up for it and that soldering directly to the pads is a bad idea. You appear to have a different opinion, whats your take?
In my attempts to actually use them, most people have told me i need to get a PCB made up for it and that soldering directly to the pads is a bad idea.
I really want that low voltage cutoff.
mamu, don't forget zener diodes also have an amperage requirement, not just a voltage one, which is why this was probably failing since the draw on the remote is 3mA. Unless I misinterpreted something here...
e. Again, use low-ESR ceramic (Murata GRM32 series) or polymer capacitors. Initial values of 188 ?F may be tried, either single or multiple capacitors in parallel. Mount these close to the converter. Measure the output ripple under your load conditions.
Output Current LimitingCurrent limiting inception is de? ned as the point at which full power falls below the rated tolerance. See the Performance/Functional Speci? cations. Note particularly that the output current may brie? y rise above its rated value in normal operation as long as the average output power is not exceeded. This enhances reliability and continued operation of your application. If the output current is too high, the converter will enter the short circuit condition.Output Short Circuit ConditionWhen a converter is in current-limit mode, the output voltage will drop as the output current demand increases. If the output voltage drops too low (approximately 98% of nominal output voltage for most models), the magnetically coupled voltage used to develop primary side voltages will also drop, thereby shutting down the PWM controller. Following a time-out period, the PWM will restart, causing the output voltage to begin ramping up to its appropriate value. If the short-circuit condition persists, another shutdown cycle will initiate. This rapid on/off cycling is called “hiccup mode”. The hiccup cycling reduces the average output current, thereby preventing excessive internal temperatures and/or component damage. A short circuit can be tolerated inde? nitely.
Due to large stray capacitance (from 2-25pF per contact point), the inductance of connections, and a relatively high and not very reproducible contact resistance, solderless breadboards are limited to operate at relatively low frequencies, usually less than 10 MHz, depending on the nature of the circuit. The relatively high contact resistance can also be a problem for some DC and very low frequency circuits. Source http://en.wikipedia.org/wiki/Breadboard
Maybe when Craig checks in he'll be able to explain how a voltage increase under load would happen when input voltage is low. I have no idea other than its internal to the converter.
Short Circuit Current (17) Hiccup technique, autorecovery within ±1% of Vout 0.02 A
Thanks, breaktru.This one has been a challenge for sure and has def abated my need to tinker with new toys... at least for a loooong time.
With Sense connected and with output cap, no issues. I removed the output cap and I get issues with loaded output voltage being higher than no load output voltage - more especially so when set output voltage >5v.I have never seen loaded output voltage higher than no load output voltage until now so is weird. If I set the no load output voltage at 5.6v, I expect to vape at 5.6v, not 5.9v. It's like the converter is overcompensating and maybe the feedback loop or whatever is off, especially at higher set output voltages.
...I've seen no load voltage a tenth or two lower than it is with a light load, but then after that, regulation error goes negative as load increases.
I'll do that. In fact, I think I'll wire up all the parts and see what's what.