Tag: mosfet

Bloody chip markings (#R6)

Geez. Just wasted half an hour finding a part number with the actual part in my hands. Maybe I’m getting old. Maybe I should have slept more or less (noon isn’t too bad on a Sunday, is it?). Maybe chip markings are getting dumber with every nonsense package invented. Maybe I should purchase components on my own so that there’s some mail history about it. Who knows.

Care to find that on your own? Now’s the time.

Hints: That’s not TO-220, obviously. It’s also not D2PAK/TO-262 (available in DPAK, though)

It’s a N-channel MOSFET with LV-TTL compatible gate threshold voltage. […]


O’CELL 26650 LiFePO4 8S 3.3Ah battery pack with BMS (WHL #28)

Same thing again – but different manufacturer. That’s what you get when you clean up your new lab… ;)

I know, might be boring to see another battery pack with almost identical specs (3.3Ah instead of 3.2Ah), but trust me, this is like night and day – or like quality China and Wan Hung Lo.

Of course these two batteries were purchased at the same time for the same thing, and they cost around the same as well. But (spoiler!): These two units work fine.

Top view:

Nice shrink wrap, proper label (shout out to O’CELL and their caring but not nagging sales people). […]


16 Bit I2C ADS1115 Module ADC 4 channel with Pro Gain Amplifier RPi (WHL #26)

Meep. We finally have a new product review, after all that editorial, recap and electronic load rubbish ;)

Today’s item in the mail is an I²C ADC on a small PCB, running four channels (or two differential ones) with 16 bit precision. Sounds nice? Well, if it holds the claimed specs, it IS a nice product! I bought it in mid-June on AliExpress for 2.06 USD. Adafruit, by the way, charges 15 bucks for the exact same thing. Do I smell profit margin?

Here’s how it looks straight out of the ESD bag:

Backside is a tad boring (keep the VDD in mind):

(there’s a floating island on the GND plane, boo!)

So, what does the friendly Asian seller claim? […]


A beefy electronic load (#P4F2)

Hello again!

I’ve been asked: What do you do with this electronic load thing? Well, I‘ve been using it as a battery torture device, what else could you do with a variable resistance device…

For a crude first step in actually testing my unit and also classifying a newly harvested set of deeply discharged 18650 cells, I slapped together some minimalistic Arduino program and hooked the thing up in parallel to the battery under test. The electronic load was set to 2 Amps with another battery, which was monitored by the Uni-T 203A current clamp. […]


A beefy electronic load (#P4F1)

Well, that was a long week…actually, it was a fortnight ;)

Here we go!

(the alignment of images really sucks when placed near the header of the post – thanks WordPress!)

So this puppy was manufactured by my new friends over at OSH Park (ordinary order, no extras) and I think I hit the express jackpot. I registered on June 8th and submitted my files – three hours later (1 AM my time on Friday) I already got notice of the panel assignment. Maybe the small size of 54mm x 31mm (2.1″ by 1.2″ for the Yankees out there) just made a perfect fit on the remaining board size and they sent it straight to production ;) As OSH Park charges 5 dollars per square inch of board area (for three units!), these were 12.75 USD including the free standard shipping. […]


A beefy electronic load (#P4)

This is a ranty introduction to the electronic load project – photos, circuits and more will be available in part 2 next week!

So…I’ve been torturing power supplies (and to a lesser extend: batteries) for ages. Usually to check their health status by comparing the current peak performance to the claimed values in the datasheet. Once you see voltage rails dropping where they should not, it’s time for a replacement of the unit, or in case of specialized PSUs, for a swap of the electrolytic caps.

But the crudity of my testing always bothered me – hooking up power resistors, measuring voltage and current, manually connecting and disconnecting the DUT, never hitting exact performance figures because of the limited selection of torture devices I had around. […]


250W DC-DC Boost Converter Adjustable 10A Step Up Constant Current Power Supply Module Led Driver For Arduino (WHL #21)

What do you do when none of your existing power supplies can provide enough power for some decent LED module? Yeah, right, you buy a bigger one!

So I did. I had some 100W/150W DC-DC converters laying around, but most of them cap at around 36V. And with the very nice Toshiba E-Core 92W LED module that wants 40V or more, that’s just not good enough (same goes for the popular 25W/50W/100W LED modules!). So the new one in my collection is this:

Some more shots:

I bought it on AliExpress back in mid-January for 4.31€ including shipping.

Tech specs are, according to the seller: 250W total output power (boost = step-up only), non-isolated output, input current 8A or 10A with additional heat sinking. […]