morganThat's how that line goes, right?
Anywho,
as a followup to yesterdays post I ditched the FT2232 in favor of the CP2102. It's like 10,000% easier to implement as it requires very minimal external components. Just a couple caps for power smoothing and some pull resistors. I like that, because I can understand it better.
It also appears to have features to integrate itself into a power management system by notifying a charge circuit of power available (0.5A, 1A, 1.5A). The early bits of research I was doing last night, it appears I should be able to hook this into the SENSE pin on the LT3652.
This change also brings about a significant part count reduction. No longer need a crystal or external EEPROM and needs fewer discrete components to operate. Between these and the price difference between the 2232 and the 2102 it's looking like a price reduction around $5+. Not too shabby.
But I still need help there! Presently I have more people following the project than have 'Skull Liked' it, so if you're reading this right now, and have not already, please give it a Skull and consider checking out my other entries!
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The $1 EFM8UB1 8-bit microcontroller can also do this. I used that chip in my charger for that reason.
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This is a very interesting looking part, I'll dig into this a bit more when I've some time.
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@K.C. Lee do you have any experience using the ADC on there? At first glance this could replace both the FT2232 and the LT3652 if capable enough.
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I have used the ADC, but they are really only 10-bit even after their "12-bit" setting as the LSB is noisy. There was also DC offset drifting (2-3mV) over time.
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I see, so even if switching to this part I'd probably want to use in conjuction with a specific solar charge controller.
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While it is quite feasible to build a power tracker charger, it'll be a lot less firmware work if you use a charger chip. I did try to build this except ran out of time, on chip FLASH space for this series was a bit too tight for what I wanted to do. They have the EFMUB2 with larger FLASH space, but the charger detection wasn't built-in.
https://hackaday.io/project/4993-dual-channel-battery-chargeranalyzer
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Might be too big a departure for this project but I'm going to buy some of these for future projects.
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I already skull'd and followed, which made this log appear in my feed.
And there I learn about the CP2102 being able to advertise its power profile, which is VERY interesting because I have a few of them somewhere and would love to unlock more juice from the USB ports :-D
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I forgot to note, only the 28 pin package exposes these features. I realized this after I got started. Hopefully this weekend I'll make a new KiCAD lib with the 28 pin version.
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and with my luck, the cheap chinese modules I have don't have the right version...
At least I'll know next time.
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I guessed that would be the case, I started designing around the 20 pin version until I realized I wouldn't have that feature. The trade-off of the small package is these feature and better thermal dissipation (if I'm reading the datasheet correctly).
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