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What is the fastest oscillator I can build for less than $1 in parts ?

Further specifications:

  • SMT only
  • Pricing for Quantity 1000
  • Stable frequency
  • Sine wave preferable
  • I don't care too much what the output voltage range is (0.5v < amp < 10v)
  • Stable and known frequency (2%)
  • Target frequency: Multiple 100s MHz
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1  
What kind of outut? Sine wave, square wave, LVTTL, LVDS, etc? What frequency range are you really interested in? I mean, do you want a 10 GHz osc? Do you just want an osc, or do you really want to build one yourself? – David Kessner Apr 18 '12 at 20:46
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Question is too vague and cannot be answered. It should be closed. – Leon Heller Apr 18 '12 at 20:54
2  
@Leon - give a guy a chance. It's much less vague now. – Rocketmagnet Apr 18 '12 at 20:57
4  
People are so aggressive here. It's really off putting, especially for newbies. – Rocketmagnet Apr 18 '12 at 21:53
1  
Ask sensible questions, then. – Leon Heller Apr 18 '12 at 22:29
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closed as not a real question by Leon Heller, Brian Carlton, Olin Lathrop, Rocketmagnet, Kevin Vermeer Apr 18 '12 at 22:45

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.

2 Answers

up vote 5 down vote

What you are asking for is more of purchasing problem than anything technical. You can buy standard surface mount oscillators for less than $1/each if you search hard enough for the right supplier.

Even Digikey has some. For example, Digikey Part #535-9777-2-ND is 100 MHz and US$0.966/each in 1000 piece qty. There are others, too. As a very rough rule of thumb, Digikey is 30% higher than going through a normal distributor. With some leg-work you could probably find a canned oscillator around 200 MHz for less than US$1.

You could also go cheaper by getting a basic crystal and building an oscillator with it and a couple of inverting gates (and some passives). Google will show you many schematics for this sort of thing. But even here, it is more of a purchasing problem than technical as you would generally design your circuit after you find the crystal.

Update: You added the stuff about sine waves after I wrote my answer. Oh well. Look for more RF specific oscillators, since they tend to be higher frequency with sine wave outputs. But I'm not that familiar with what is available for RF.

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It's a bit of a purchasing question, but it's also quite a design question. It's a lot more than something like "Which is the best crystal to get?". I really don't know much about building oscillators, and would like to learn more. – Rocketmagnet Apr 18 '12 at 21:06
(I'll get in trouble for this) But I'll tell you why it's not really a purchasing problem: The $1 thing is really to limit answers to oscillators I can make from simple parts. Otherwise the answer would be "Buy an expensive oscillator module". – Rocketmagnet Apr 18 '12 at 21:10
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@Rocketmagnet Yeah, sometimes it's better to ask the real question than to try and be subversive. – David Kessner Apr 18 '12 at 21:44
Damn, I love being subversive. – Rocketmagnet Apr 18 '12 at 21:49
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Can you please put the final nail in this question's coffin, if you haven't already ? – Rocketmagnet Apr 18 '12 at 22:13
up vote 4 down vote

This mess ought to ring nicely:

The frequency will be very unpredictable and unstable, but you asked for fast and cheap.

Added:

A PIC 10F200 can be used as a 1 MHz oscillator good to a few percent with no other part than a bypass cap. That will be well under $1 each.

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Can you give a very rough estimate of the frequency ? – Rocketmagnet Apr 18 '12 at 20:51
@Rocketmagnet - It's a function of the propagation delays of the 74HC04. It will vary based on who made the IC. – Connor Wolf Apr 18 '12 at 20:56
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@Rocket: No, I can't. Your original spec said nothing about frequency stability or accuracy. You mostly wanted cheap, and this is definitely cheap. – Olin Lathrop Apr 18 '12 at 20:59
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@Olin - It's a fair point. I gave you an upvote. – Rocketmagnet Apr 18 '12 at 21:01

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