Amplifier IC supply voltage parametric field: PVDD or DVDD? - Page 1
Forum section: electronics / projects

author: rs20
author_rank: Super Contributor
timestamp: November 20, 2021, 10:17:22 pm
content: I have strong opinions about this, but I'd like to check if my opinions align with general "consensus".Digital-input Class D amplifier ICs combine a DAC and a class D amplifier into a single IC (at least, conceptually). So unsurprisingly, they have multiple supply pins, each with their own expected voltage ranges:PVDD -- a supply feeding the class D push-pull stage; thus actually providing the power to drive the speakers. Typically ranging within 3.3 ~ 40V.DVDD -- digital logic voltage, used for all the computational stuff inside the IC. Typical logic IC levels, so ranging within 1.8 ~ 5V or so.And sometimes others, like AVDD, which are often the same level as DVDD.Meanwhile, distributors like Element14/Digikey etc have parametric search over a whole bunch of parameters, but I'm interested in the "Supply Voltage" parameter in particular. The poll question is: If you were in charge at a distributor, which datasheet spec would you use to fill in the "Supply Voltage" parameter? What do you think is most useful for engineers trying to select such parts?

author: Benta
author_rank: Super Contributor
timestamp: November 20, 2021, 11:47:24 pm
content: Who cares?Then the distributors should change their paramatric tables. It's up to them.And why is this in the "projects" area? I don't see a hint of a project here.

author: rs20
author_rank: Super Contributor
timestamp: November 21, 2021, 08:19:36 am
content: Quote from: Benta on November 20, 2021, 11:47:24 pmI'm a little puzzled by this message -- I care, that's why I asked the question. As I hinted at, when I form an opinion, I seek out contrary opinions to check myself. This is that.And this section is titled "Projects, Designs, andTechnical Stuff". This is technical stuff, and it's also a questionforfolks who design using these sorts of ICs.

author: Ian.M
author_rank: Super Contributor
timestamp: November 21, 2021, 09:51:28 am
content: The logic supply voltage isn't particularly important - level shifters and LDO regulators are relatively cheap. OTOH the output stage supply voltage range is absolutely critical to your overall design, as it must match your power source and also be sufficient for your required output power and load impedance.However as long as distributers let web developers and marketing wonks run their websites and backend databases, don't expect any improvement. 'Parametric search' is just another checkbox far down their list of development priorities, that only has to work well enough to pass a 5 minute presentation to C level execs.

author: rs20
author_rank: Super Contributor
timestamp: November 24, 2021, 03:19:50 am
content: Thanks Ian! That aligns with my own thought process perfectly :-)As for not expecting any improvement; I see what you're saying, but I do still take the time to point out opportunities for improvement. Customers failing to offer constructive feedback isjust as badas companies failing to improve in response to constructive feedback, because both are required for improvement to occur! But I realize I'm being quite naive and idealistic.