Which is most PBP-Friendly external ADC?

[CuriousOne]

Hello.

I need a simple, 1 channel input, external ADC, which can do 16 or more bits. I don't need fast speeds, I need only 100-200 samples per second sampling speed. I've searched digikey, but there are so many....

So I'm asking, maybe someone has any practical experience using external ADC with PBP ?

[Acetronics2]

16 bits @ 100-200 sps ???

Good luck !!!

Alain

[pedja089]

It might be overkill, but I like ADS1246 (https://www.ti.com/product/ADS1246?qgpn=ads1246).
You can use shiftout/shiftin
EDIT:
This might be more suitable for you
https://www.ti.com/lit/ds/symlink/ads1119.pdf?ts=1687034239450&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct %252FADS1119
Never used, but it look simple....

[Ioannis]

Also this maybe a good alternative

https://gr.mouser.com/ProductDetail/Microchip-Technology/MCP3426A0T-E-SN?qs=icxrp76fIjCsyZVqfEl2BQ%3D%3D

Ioannis

[HenrikOlsson]

It seems like the MCP3426 is only capable of 15sps at 16 bits resolution though.
I'm curious if the 100-200sps is an actual specification or just a number drawn out of the air, perhaps 10sps is enough in reality?

I stumbled upon the AD7680. It's "driven" by the SPI-interface clock and they claim up to 100ksps when clocked by a 2.5MHz SPI clock.
Given the required 200sps the needed SPI-clock speed is way lower so SHIFTIN should certainly be an option. And it's a availble in a 6-pin SOT23 package.

[Ioannis]

I think there will be so many data to process with a PIC. I do not know what exact processing this will be but I feel it will be very intensive with massive data manipulation...

Ioannis

[CuriousOne]

I want to measure AC voltage without rectification, but as I see, all these ADC have 50/60Hz rejection....

[HenrikOlsson]

Perhaps the ADS7028?
It's a 12bit converter but it has a built in RMS-module producing a 16 bit true RMS result. But yeah, you going to have to sit down with the datasheet to get it going.

[tumbleweed]

I'm curious as to why you would want/need microvolt resolution to measure the AC voltage?

[amgen]

I'm curious as to why you would want/need microvolt resolution to measure the AC voltage?

That is a good question, but on that subject, I have been wondering how the solar panel 'micro inverters' or whatever other method they use to introduce the current from the solar panels directly into the main incoming power/voltage/current......
With synchronizing 2 generators, it is easy to vary load from each by switching them together when 'in-phase' where they 'lock together' then increase or decrease the governor speed setting to vary how much watts or killo=watts each unit carry.
:rolleyes::eek:

[tumbleweed]

It you're trying to sync two AC signals I would think the easiest/most reliable way would be to use the zero-crossings.

[CuriousOne]

I want to make myself a fast, at least 30fps screen update multimeter, which will have no range switching (either manual or automatic), and will have decent resolution in 0.1V-600V range. I already built one using built-in ADC of PIC16F1939, but 10 bits of resolution are definitely not good enough.

By fast sampling the input voltage, I guess, I can measure AC voltage too, without additional losses caused by rectification.

[amgen]

I don't want to infringe on his post here........

It you're trying to sync two AC signals I would think the easiest/most reliable way would be to use the zero-crossings.
The solar makes DC voltage, sometimes they stack the panels to get say 120 VDC or more, then somehow (with inverters that use PWM) introduce current onto/into the pure sine wave of the utility ???

[Ioannis]

Yes this is the main idea. Some installation have even higher DC voltage (reducing the current).

Ioannis

[mpgmike]

It is called a Trace Inverter. Microchip has Reference Designs, as I'm sure TI and Analog Devices do. The quickest path to success is find a reference design.

Microchip.com then Solutions in header, Power Management and Conversion, DC to AC Power Inverter Solutuions.

There are several designs to look at, which should at least give you ideas.