Can I modulate ASK/FSK ICs by voice? Are them only for data?

[Ninap]

I wish to design a small IC PLL voice modulated transmitter (433MHz band).
I found several ICs, but from what I've understood, they appears as only data transferring... I found ASK and FSK 8 legs transmitters, but I don't know if they are capable to be modulated by voice (by a varicap diode).
If it's not possible to use them, any idea what 8 pin SMD device can be used? I have an working device, but the guy who built it deleted the info from the IC.
Thanks for any information, and maybe.... any schematics link?
Nina

[Tomi Engdahl]

I found several ICs, but from what I've understood, they appears as only data transferring... I found ASK and FSK 8 legs transmitters, but I don't know if they are capable to be modulated by voice (by a varicap diode).

What specific ICs did you take a look ?

Those ICs designed for data transfer using ASK or FSK method are basically just designed for this specific application in mind. You can only run data to their modulation pins.

It might be possible to hack them for voice transmission. AM modulation would be quite propably with some external modulation circuit at least somehow. Might be work or not.. If you have that tramitter IC, then add a suitable external modulator, possibly some filtering and then final amplifier unless we are talking about very low power.
Depending on the IC design, at some cases it could be maybe possible to do FM modulation by changing the IC RF oscillator frequency with suitable circuitry (capacitor diode in the LC or crystal osicllaotr circuit slightly modulating the frequency). Could work with some ICs I think, maybe not with some other designs..

[Ninap]

Thank you very much Tomi,
I put a close up picture on an ftp - it's too large (1.2M) to upload it here.
http://www.csharpit.com/bug.jpg
There is a varicap diode on the CS of the PCB. So far I found that the ASK/FSK ICs use a x32 multiplication - but I'm trying to finf this particular one. At Maxim I found the wrong cases...

Thanks again.

[DD]

Thank you very much Tomi,
I put a close up picture on an ftp - it's too large (1.2M) to upload it here.
http://www.csharpit.com/bug.jpg
There is a varicap diode on the CS of the PCB. So far I found that the ASK/FSK ICs use a x32 multiplication - but I'm trying to finf this particular one. At Maxim I found the wrong cases...

Thanks again.

A bit late but anyway
The chip you are looking for is from Melexis TH72012 .
Allmost any ASK FSK can do the job even rfPIC12f675