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Take this chip as an example: http://www.maxim-ic.com/datasheet/index.mvp/id/3491.

It says that the frequency range is 8.1kHz to 133MHz on the main output and 8.2MHz to 133MHz on the reference output. But, to my untrained eye it doesn't say much else.

The datasheet left me with a few questions:

  • What kind of oscillator is it? Sine wave, triangle, saw tooth?
  • It says it only needs a single +5v supply, but what if I wanted the sine wave to oscillate between, for example, -2.5 volts and 2.5 volts?

I know I can build an oscillator with an op-amp, but this question doesn't relate to that. I'm merely curious about the nature of chips like the one I posted.

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The output is a square wave compatible with digital logic. The "high" state is at least 2.4 volts and could be as high as the power supply. The "low" state is between 0.0 and 0.4 volts.

Chips like this are used for generating clocks for digital logic and are not suitable for making sine waves.

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  • \$\begingroup\$ Thank you. Is there a specific name (industry name, maybe?) for a sine-wave oscillator chip? Very low frequency, like < 10kHz. \$\endgroup\$
    – Chris Laplante
    Commented Jan 4, 2012 at 2:48
  • \$\begingroup\$ Never mind, waveform generator is what I'm looking for: maxim-ic.com/datasheet/index.mvp/id/1257/t/al \$\endgroup\$
    – Chris Laplante
    Commented Jan 4, 2012 at 2:57
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    \$\begingroup\$ @SimpleCoder Nope. Most of the time people don't really want sine waves at those frequencies. What they really want is to move a motor, or make a light "throb", or make some crazy noises. For most of these things there are better ways to achieve that than starting with a sine wave osc. For example: making crazy audio could be done with a simple DSP + DAC, and it would likely have better quality than a normal sine wave osc. \$\endgroup\$
    – user3624
    Commented Jan 4, 2012 at 2:58
  • \$\begingroup\$ @SimpleCoder Too bad that Maxim part is discontinued. And the similar part form Exar is also gone. \$\endgroup\$
    – user3624
    Commented Jan 4, 2012 at 3:04
  • \$\begingroup\$ Yeah, I see a ton of discontinued parts that do what I want on various manufacturers' sites. I guess I'll just have to suck it up and build an op-amp one. Sigh. \$\endgroup\$
    – Chris Laplante
    Commented Jan 4, 2012 at 3:06

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