Sine Source IC !!!

[State Machine]

I believe that some of you may be interested in this handy little IC. I plan to get a couple of these just to play around with. I will have to study the data sheet in detail to see what the frequency resolution is. It seems like it would have many applications as an LFO, carrier source, or audio oscillator.

http://mix-sig.com/MSLOSC.pdf

At a glance: 15 Hz to 64 kHz sine wave with digitally controlled frequency and attenuation in a small outline 8-pin package. Synchronous Serial Interface.

The data sheet speaks for itself.

[Macaba]

It gets more into the realms of DCO, because you'll need a microprocessor to send the data signals to control the sine chip. Which, argueably is ok if you use an ADC and scale the voltages.

[State Machine]

I agree on that with you my friend. I love the analog stuff but am also a digital freak! I usually have some sort of controller in my projects so feeding it data is no problem.

I suppose if I wanted to do voltage control of frequency using this IC, I would have to use an A/D and some scaling.

If I am not mistaken, I believe Donald Buchla uses this technique alot to control DCO's in his new 200e series modules. I better do more research though before I put my foot in my mouth.

There is also the exclusive use of MIDI to control the thing also in lue of voltage control. For example, the MIDI note on/off and velocity messages could just be transformed, via look up table, then feed the chip it's frequency and attenuation data.

Thanks for your feedback ...

[Macaba]

Yeah, i'm a digital guy too, so GO FOR IT!

MIDI interpretation by a microprocessor/controller sounds a good idea actually, it eliminates having a MIDI to CV stage! Fabulous!

[toppobrillo]

cool IC. wonder how much they are? yeah i like digital control too.

you know, looking at the other devices that this company [and others like it] produce[s] on a relatively small scale makes me really curious as to why noone [that i know of] has taken the initiative to develop new LSI music-synthesis ICs, or at least buy and reproduce the old Curtis and SSM designs.?? highly integrated ICs made specifically for sound synthesizer equipment.. [useful in other areas too!]

if i ever come into some $$$, i would definitley consider pursuing this.

[State Machine]

Topp,

Thats an interesting thought. Those chips are rare and it would be nice for a company to produce those types of IC's again. The chips are classics! I have one of the SSM VCA chips in my stock. Unfortunately it's an era of big business and big profits and there probably would not be enough of a demand for them to turn a good profit. Thats what probably keeps companys from producing such a line. I agree with you though, this company would be the most probable to do such a thing.

What I will do after I get back from the "analog heaven" gathering this weekend is enquire about getting some of these sine chips, maybe even get a few samples. If so, I would even send you one or two dude!

While we are on the topic of specialized audio chips, and probably a topic all it's own, is the possible use of some of those mixed signal controllers from Cypress Semiconductor for synthesis applications. I believe they are the PSOC, (Programmable system on chip), series that have a microcontroller and programmable analog cells on one chip! Something I have wanted to play with for a while.

Chat later !

[DrJustice]

Interesting chip. Too bad about the 15Hz lower limit, thinking about LFO applications. One thing that might be worth considering is that since it is a PLL based device, there is some settling time when changing frequency; the datasheet says 15ms for f0 = 1kHz.

It may be worth checking out general DDS chips like the AD9832. That chip is a phase accumulator table lookup oscillator, so frequency changes are instantaneous and it will go down to DC. It is easily sourced - can even be bought straight from AD's own webshop at USD 8.23 for a single chip (or samples for free...).

Of course, going for FPGAs or CPLDs (or a small DSP even) with DACs would give much more flexibility, but that may be going too far in this context.

DJ
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[Macaba]

[State Machine]

Macaba,

Sounds like a good topic for discussion. It should get lots of activity.

[State Machine]

DJ:

Thats a good observation concerning the 15 hz lower limit. This lower limit certainly limts the devices use as LFO. Perhaps it can be used as a programmable carrier source for a balanced modulator?

The settling time may be a limiting factor in terms of frequency agility. It's interesting that tere is no graph showing the settling time vs. frequency setting.

Still a cool IC though

I agree, the FPGA approach would be an optimum design approach in terms of flexability in designing a digital oscillator.

[toppobrillo]

yeah, or, an easier way to make a quadrature vco for a frequency shifter.