It has better specs than PCM5242 DAC, cost quiet the same price (has better specs than PCM1863 ADC too), needs a single power supply, is only 4x4 mm wide and is totally hardware configurable.
I don’t know if a kernel module will be needed or if a standard I2S hardware setup will just work out of the box.
Well, it’s a bizarre situation: the chip(*) is always out of stock. I wonder if it has ever been sold elsewhere. Maybe because on TI’s website, they says TAC5242 is in “PREVIEW”:
This product is not in production, although prototype or experimental parts are available for purchase. This product may be subject to changes during engineering validation until it is released to production.
But I asked last week TI for an Evaluation Kit (wich isn’t sold by any third party distributor like Mouser, Digikey …).
And I get a response today:
Thank you for contacting Texas Instruments.
This case is created for your request for Product number TAC5242EVM-K-REQ and it has been acknowledged. We have forwarded it to a specific department for business review and approval.
Please allow approximately 1 week or more for processing. Upon approval, download instruction will be sent to your E-mail.
Also, please take note that we cannot guarantee the approval of this request and let us know if you have not received any feedback after two business days.
So wait and see, and hope
The chip has excellent specs and just need a couple of capacitors on power rails + input/ouput filters. It could be a good candidate for a “base module” that can be replicated for multichannel digital audio on a RBPi 5.
It should reduce the BOM cost compared to the combo pcm1368 + pcm5242 (2.813€/u when 1000 units buyed)
(*) they are others chips in the same manner but DAC only or ADC only, some are hardware controlled (like the TAC5242) while other are software controlled via I2C: TAD5212 , TAC5212 , TAC5111 , TAC5242 , TAA5242 , TAA5212 , TAC5211 , TAD5112 , TAC5142 , TAC5112 , TAD5142
TAC = codec
TAA = ADC
TAD = DAC
TAx51yy: software control
TAx52yy: hardware control
I would think we’d want to use one of its software-I2C controlled siblings, like the TAC5212,https://www.ti.com/product/TAC5212, in order to change settings flexibly without requiring hardware changes in Zynthian.
What I like here is simplicity.
IMO, software controlled IC’s are cool when software (in kernel / alsa / boot time -with their specific overlays files-) exists !
Even the simpliest pcm5102a (totalty hardware controlled) has a kernel driver and a “hifiberry-dac” overlay.
In (RBPi) AudioLinux Kernel source, there’s also the pcm3168, wich could be a really good candidate too, with its 6 audio inputs and 8 outputs. But it has a more complicated kernel driver. Because of its lots of features controlled through I2C or SPI. And no specific alsa-asoc driver (like rpi-simple-card.c) or overlay file.
TAC5242 can be “software controlled” too (“kind of”) but by staying in Zynthian"s user space level ( <=> set with a GPIO connected to some MDx pin, the level to high or low will change settings like sample rate, master or slave clock producer or clock consumer and so on). Something you don’t have that much to tweak on. When it’s done, … it’s done
Some CODEC IC’s have even some avanced features like build in audio effects in a so called “programmable DSP” (*).
I believe this could be usefull in some use case, but in Zynthian’s world, that’s the Zynthian job. We do just need the correct device for our gear: good A ->D and D->A converters and let Zynthian do the job for audio routing, audio effects and so on.
(*) with mostly proprietary softawre developement tools.
