Can't find the data sheet

Hi all,

Im considering building a custom am/fm radio for a project car i have and came across silicon labs who make many different automotive am/fm radio tuner ic's. Ive found the one i'd like to use but can not for the life of me find a comprehensive datasheet like i'm used to with most components. The best i can come up with is this from their website....

si47901 data short

It has only the bare minimum of information with out even a proper pin description. There are other documents that relate to programming and schematic examples etc but none seem to relate to this ic specifically.

Do they keep this sort of information aside only for major customers or am i missing something?


I think you will find that the device is purely for manufacturers to use, rather than for our hobbist applications.
The only solution is for you to contact Silicon Labs, unless you want to buy thousands of them, they may not be interested.

Tom... :slight_smile:

The full datasheet may require a non-disclosure agreement to be signed. Try contacting them and ask if they do samples... You never know. ?

Thanks everyone,

Ive contacted Silicon labs a couple of times requesting samples with no reply so far. Ive found a place i can buy them 2 at a time so might email them asking for a datasheet as well. I had wondered if perhaps theyre just not interested in the hobby scene but was hoping to find a datasheet anyway.

DrAzzy, thanks. Ive seen that document but it doesnt state the si47901 as being applicable. Im sure theyd be very similar but it's also just a programming guide, not a datasheet.

Ill keep emailing and see what they come back with.


How about the Programming guide? 302 pages, link already given.

Hmm, yeah, doesn't seem to be much there. 2014 datasheet, are the parts obsolete already?

Mouser carries a bunch of parts

Yeah i think ill just have to keep trying to contact them via email.

Ive seen multiple different parts that they offer but for various reasons had selected that particular ic. Perhaps ill have to try and find something else.

Thanks everyone

I agree, finding a manufacturer that does support the hobbyist market will make life much easier.

I agree, finding a manufacturer that does support the hobbyist market will make life much easier.

There would be very few chip manufacturers indeed that would have a reason to support the hobbyist market. Can you think of such a reason?

Such support is indeed, what these - and similar - forums are for. :grinning:

I have had success telling the manufacturer that "it is for a prototype." They don't usually ask too many questions. If they really want to know how many thousands you are going to buy then either tell them you are still evaluating the market or tell the truth that you only want to buy one.

Maybe you will make something that thousands of hobbyists want to buy. I am often amazed at how many obscure sensors and things are sold by Sparkfun.

Is there some piece of information you're looking for that isn't covered by the programming manual which I linked? (which took me less than 5 minutes to find with google) When the datasheets are small, try searching with the word "manual" instead of "datasheet" - we're sort of spoiled by Atmel's comprehensive datasheets, where they give you a datasheet for each part that includes all the information on it. Most manufacturers, when they have a bunch of "similar" products, provide short datasheets, and one much larger "manual", "programming guide" or similarly named document with the full details (STM does this with their STM32 line; I find it annoying, but that's how it's done, so we have to deal with it)

For buying small quantities of chips from major manufacturers, just use mouser/digikey - IME it's not worth the effort to try to bum a few chips off the manufacturer (unless you value your time at sub-minimum wage).

Sorry everyone. I've been overseas and unable to reply.

As i mentioned at the start i have the programming guide and schematic examples but none of these documents state the si47901 as being relevant. I have a supplier that supplies the chips in small quantities (plus astronomical shipping :frowning: ) but they still only link to the data short. Not a full data sheet or anything specifically for this chip. Basically, any info i can find relating specifically to this ic is sparse and i feel there must be more out there.

So this morning i've spoken to a local distributor who is going to chase this up for me and see if he can get me the documents i need plus some samples if available.

I'll let you all know what i hear back from him.

In the mean time i'll start looking for something else that will suit my needs.

Still no reply from Silicon Labs themselves.

Thanks everyone

Have you looked for other ideas?

google arduino automotive am/fm radio

There are even some YouTube clips.

Tom.... :slight_smile:

There would be very few chip manufacturers indeed that would have a reason to support the hobbyist market. Can you think of such a reason?

Old hobbyists are probably not so interesting. But teaching young hobbyists to use your products may be very valuable IMHO - some of them will grow up into real engineers. I think they will prefer your products if they are already familiar with them and your tools. Provided your products are price and performance competitive ofc.

I am so happy someone has the exact same problem as me!

We are looking for a FM receiver with both (A) digital (DAB) decoding support and (B) antenna diversity receiver and (C) RDS for analog FM.
The Si47901 is pretty much the only chip so far that supports all that and is somewhat available. But the manufacturer openly only provides the two page specsheet, no manual, or programming guide or application notes.

If you find them please PM me! And if you find a more accessible, alternative FM receiver chip that can do (A), (B) and (C) please let me know as well!

PS: DrAzzy, the AN332.pdf that you linked is for a completely different series of Silicon Labs chips. Easy mistake to make since they are named similar.