Simple 30 channel current measuring approach?

[zzattack]

I'm looking for some advice for the approach of a project that I want to do. My desire is to continuously sample currents going into about 30 LED panels simultaneously. A sample rate of 2Hz would suffice, and the measurements are to be transfered over UART to a Raspberry Pi.

What I have in mind is to use a ACS712 for the current measuring of each channel, and some multi-channel analog to digital converters along with a STM32F0 for reading out the ADCs, either over SPI or I2C. The TI ADS1158 seems a reasonable choice for the ADC, but from the datasheet its SPI interface seems quite annoying to deal with. There's a bunch of 8-channel devices that also seem capable, but it's hard to judge whether any of them integrate nicely with some microcontroller code. Ideally, I wouldn't need too many of them (will prototyping about 10 by hand..), so a component that's available in a hand-soldering friendly package is prefered.
Any suggestions, pitfalls or advice for things I should take into consideration are appreciated.

[SiliconWizard]

If your sample rate is that low, then you'll have to seriously low-pass filter the current measurements themselves; in which case, "simultaneous" sampling is useless IMHO. You can just use one ADC and an additional analog multiplexer.

Note that that's what the ADS1158 does - it just has an internal analog MUX. You'll need two of them. They are about $10 each (for low quantities.) I don't see what the problem is with its SPI interface.

If the voltage span fits your requirements, you could consider using a 32-channel MUX instead, such as the ADG731, and then a single-input 16-bit ADC (if you really need 16-bit?) That's still two chips, but that'll be cheaper. Oh and if 12-bit is enough, you could consider using the internal ADC of some MCU, many do have 12-bit ADCs these days. The ADG731 itself is about $5. It's available in TQFP, which is easy to hand solder.

[Terry Bites]

https://www.tindie.com/products/fercsa/32-channel-adc-wi2c-for-arduino-raspberry-pi/#specs