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60 Hz Frequency Reference

60 Hz Frequency Reference

60 Hz Frequency Reference

(OP)
I’m looking for an IC to build a 60 Hz (+/- 1%) frequency simulator.  Output should be a 12 to 20 VPP sine wave.  I would prefer to use a 12 VDC power source, but that is not likely given the amplitude of the output.  A 24 VDC power supply would be the second choice.  I know that I could use a 555 timer, but they require external components and I want to keep the device as small as possible.  Has anyone seen a dedicated chip for simulating 50 or 60 Hz?  Any other ideas?

RE: 60 Hz Frequency Reference

If frequency [Fr] is not critical : 555 is ok. else use xtal.

If waveform is critical (<1% error) Higher fr. osc, divider-
sine PROM - DAC  ELSE function generator chip. If even less
critical (>5% error ) :lp filter.


<nbucska@pcperipherals.com>

RE: 60 Hz Frequency Reference

For voltage you can use an H driver for up to 24V.
-- you neglected to mention how much current do you need
to supply.

If difficulty, send fax# for schematics anf full specs.

<nbucska@pcperipherals.com>

RE: 60 Hz Frequency Reference

Rawlings,

Try ML2036 or ML2035 from fairchild, this a simple DDS frequency generator with senoidal output. You need add a low pass filter and operational amplifier to obtain a desired output level. This device operate in any frequency from DC to 25KHz.


http://www.fairchildsemi.com/an/AN/AN-42025.pdf

Regards,

M3

RE: 60 Hz Frequency Reference

If you live in an area where line power is 60 Hz, then why not just use a transformer and a potentiometer to control the amplitued?  If you require a buffered signal, then a DC supply will also be needed.  I believe that line frequency is very stable.

RE: 60 Hz Frequency Reference

I agree with garry.

Unless you have some good reason to avoid the transformer, I'd just dig up one of the old wall wart transformers (from some long-forgotton home electronics) that you most likely have laying around in a junk drawer somewhere in your kitchen or basement.  Just plug it in and voila, you have a free, very accurate and very stable 60Hz reference source.  

Matter of fact, it's a good enough reference that not only old clocks, but some old TV's used to use the power supply for their time base.

RE: 60 Hz Frequency Reference

There are a lot of good stable Wien bridge oscillator circuits out there that will probably do the trick for you and also have very low distortion figures. You could use a function generator chip, but you must keep in mind they are terribly sensitive to temperature changes, even if the component values used are temperature stable.

RE: 60 Hz Frequency Reference

Depending upon frequency accuracy required, one choice might be a Fairchild ML2036 chip.  Data sheet at:
http://www.fairchildsemi.com/ds/ML/ML2036C.pdf
app note at:http://www.fairchildsemi.com/an/AN/AN-42000.pdf
Available from Arrow electronics for $8.81.  It runs on 5 volts, so you'll have to amplify it up and produce current u need.  Also u have to load divider number in and provide either an external clock, or a ref crystal.  It gives you about 1 Hz steps in produced frequency.  Suitable xtals are listed on data sheet, or i'm gonna try a color telly xtal, cause i have those on hand.  Implemented, this shouldn't cost more than $25 or so for low power levels.  

I need it for a 50 Hz ref for a VCR (you can play PAL tapes on a usa vcr (NTSC) if you provide a 50 Hz ref to the head wheel circuitry.  video comes out at a 50 Hz frame rate tho, so you need a tv with a vertical hold control to display picture.  

Have fun..

Rab

RE: 60 Hz Frequency Reference

Hi Bunny01:

I don't believe the VCR speed control would need sine
I think XTAL--digital divider and perhaps amplifier
should do it.

<nbucska@pcperipherals.com>

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