CD4060 Xtl Osc. Circuit
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From: Spehro Pefhany on 13 Mar 2010 16:36 On Sat, 13 Mar 2010 13:15:43 -0600, the renowned "krw(a)att.bizzzzzzzzzzzz" <krw(a)att.bizzzzzzzzzzzz> wrote: >On Sat, 13 Mar 2010 13:53:23 -0500, "Martin Riddle" <martin_rid(a)verizon.net> >wrote: > >> >> >><krw(a)att.bizzzzzzzzzzzz> wrote in message >>news:6qmnp598tm30hlmvgvdne65ps3msbb8q3r(a)4ax.com... >>> On Sat, 13 Mar 2010 09:05:24 -0800, John Larkin >>> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>>On Sat, 13 Mar 2010 08:42:27 -0800, Fred Abse >>>><excretatauris(a)invalid.invalid> wrote: >>>> >>>>>On Fri, 12 Mar 2010 16:28:07 -0800, John Larkin wrote: >>>>> >>>>>> I never buy crystals for things like this. They have a high >>>>>> probability of >>>>>> not working, and you wind up fiddling with capacitors and such. >>>>>> It's >>>>>> easier to but a packaged, working crystal oscillator, already tuned >>>>>> to a >>>>>> couple PPM, guaranteed to oscillate, for $1.50 or thereabouts. >>>>> >>>>>Me, too. Amplifiers oscillate, oscillators don't ;-) >>>> >>>>We've just started using silicon oscillators, in SOT-23 sized >>>>packages, for things where 1% is good enough. We're using one part >>>>that's pin strappable for 8-4-2-1 MHz. >>> >>> A seven pin SOT-23? >> >>I think its this Linear part >><http://cds.linear.com/docs/Datasheet/6900fa.pdf> >>There are others tho. > >Neat (but sloppy - 1/5% to 2% error). That's a trinary input (1/10/100) in a >SOT-23-5. John was suggesting 1-2-4-8 binary inputs. I've never seen a >SOT-23-7. Up to six pins on a "SOT-23" I can understand, but where does the >seventh pin go? Probably an SOT-23-8. There are some 32-bit microcontrollers in 33 pin packages. The thermal pad is the ONLY ground pin IIRC. Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff(a)interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
From: Joerg on 13 Mar 2010 17:24 Phil Hobbs wrote: > On 3/12/2010 7:45 PM, Joerg wrote: >> Steve Upton wrote: >>> I have copied the CD4060 part of the CMOS synthesizer in the link >>> below to the letter, but it does not work. I am using a 12VDC SLA for >>> supply. It tries to start when I tease the caps, but then dies. >>> >>> I've spent hours tinkering to no avail. Can anyone see what is might >>> be going amiss? ... >> >> >> Not knowing which frequency you are using, the 100k is way too low. I >> never go below 1M. Also, the burden caps are highish, 100pF is a bit >> much. >> >> >>> ... Or can anyone please provide a similar circuit that works? >>> >> >> Yup: >> >> http://www.edn.com/contents/images/6553623.pdf >> >> >>> http://www.redclifferadioclub.org.au/QRM/2006%2010%20-%20October%20QRM.pdf >>> >>> >>> >> >> How on earth could you guys call your club bulletin "QRM"? ... :-) >> >> (for non-hams: QRM means noise, of the undesired kind, meaning not from >> a rock band and stuff) >> > Nah, noise is QR*N*. QRM is interference, usually other random lusers > gassing about their equipment. > I think the definition is that QRN is atmospheric noise. Distant lighting and so on. QRM is man-made noise which is in the majority these days. Switch mode supplies, CF lamps and so on. And yeah, also splatters from the guy 5kHz down the road gassing about his big honking amplifier :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Grant on 13 Mar 2010 18:42 On Sat, 13 Mar 2010 11:01:11 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)My-Web-Site.com> wrote: >On Sat, 13 Mar 2010 00:20:46 GMT, steveupton(a)gerber.com (Steve Upton) >wrote: > >>I have copied the CD4060 part of the CMOS synthesizer in the link >>below to the letter, but it does not work. I am using a 12VDC SLA for >>supply. It tries to start when I tease the caps, but then dies. >> >>I've spent hours tinkering to no avail. Can anyone see what is might >>be going amiss? Or can anyone please provide a similar circuit that >>works? >> >>http://www.redclifferadioclub.org.au/QRM/2006%2010%20-%20October%20QRM.pdf >> >>Steve Upton > >What crystal are you using? > >The pi network components are frequency/crystal dependent... "...tries >to start when I tease the caps" suggests that's your problem. Funny you mention that, I ended placing a small cap (22pF) from pin 9[1] to ground to get reliable oscillation -- but that was at 8MHZ with a HC4060. A later circuit I used capacitor instead of the series resistor to the crystal (as recommended by the HCMOS oscillator appnote). [1] Pin 9 is supposed to be open with xtal circuit. I know this doesn't directly apply to OP's issue, but it shows 'finger' teasing can give an idea whether the circuit is trying to oscillate. Grant.
From: Jim Thompson on 13 Mar 2010 19:07 On Sun, 14 Mar 2010 10:42:55 +1100, Grant <omg(a)grrr.id.au> wrote: >On Sat, 13 Mar 2010 11:01:11 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)My-Web-Site.com> wrote: > >>On Sat, 13 Mar 2010 00:20:46 GMT, steveupton(a)gerber.com (Steve Upton) >>wrote: >> >>>I have copied the CD4060 part of the CMOS synthesizer in the link >>>below to the letter, but it does not work. I am using a 12VDC SLA for >>>supply. It tries to start when I tease the caps, but then dies. >>> >>>I've spent hours tinkering to no avail. Can anyone see what is might >>>be going amiss? Or can anyone please provide a similar circuit that >>>works? >>> >>>http://www.redclifferadioclub.org.au/QRM/2006%2010%20-%20October%20QRM.pdf >>> >>>Steve Upton >> >>What crystal are you using? >> >>The pi network components are frequency/crystal dependent... "...tries >>to start when I tease the caps" suggests that's your problem. > >Funny you mention that, I ended placing a small cap (22pF) from pin 9[1] >to ground to get reliable oscillation -- but that was at 8MHZ with a >HC4060. A later circuit I used capacitor instead of the series resistor >to the crystal (as recommended by the HCMOS oscillator appnote). > >[1] Pin 9 is supposed to be open with xtal circuit. > >I know this doesn't directly apply to OP's issue, but it shows 'finger' >teasing can give an idea whether the circuit is trying to oscillate. > >Grant. My rule of thumb, which seems to work with every inverter-style crystal oscillator I've ever tried: Use capacitors as recommended by the crystal specification... if it says 15pF, that means 30pF on EACH end to ground. Then choose the resistor based on 45� phase shift with the first capacitor (at the crystal frequency). ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | The only thing bipartisan in this country is hypocrisy
From: krw on 13 Mar 2010 19:27
On Sat, 13 Mar 2010 16:36:29 -0500, Spehro Pefhany <speffSNIP(a)interlogDOTyou.knowwhat> wrote: >On Sat, 13 Mar 2010 13:15:43 -0600, the renowned >"krw(a)att.bizzzzzzzzzzzz" <krw(a)att.bizzzzzzzzzzzz> wrote: > >>On Sat, 13 Mar 2010 13:53:23 -0500, "Martin Riddle" <martin_rid(a)verizon.net> >>wrote: >> >>> >>> >>><krw(a)att.bizzzzzzzzzzzz> wrote in message >>>news:6qmnp598tm30hlmvgvdne65ps3msbb8q3r(a)4ax.com... >>>> On Sat, 13 Mar 2010 09:05:24 -0800, John Larkin >>>> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>>>>On Sat, 13 Mar 2010 08:42:27 -0800, Fred Abse >>>>><excretatauris(a)invalid.invalid> wrote: >>>>> >>>>>>On Fri, 12 Mar 2010 16:28:07 -0800, John Larkin wrote: >>>>>> >>>>>>> I never buy crystals for things like this. They have a high >>>>>>> probability of >>>>>>> not working, and you wind up fiddling with capacitors and such. >>>>>>> It's >>>>>>> easier to but a packaged, working crystal oscillator, already tuned >>>>>>> to a >>>>>>> couple PPM, guaranteed to oscillate, for $1.50 or thereabouts. >>>>>> >>>>>>Me, too. Amplifiers oscillate, oscillators don't ;-) >>>>> >>>>>We've just started using silicon oscillators, in SOT-23 sized >>>>>packages, for things where 1% is good enough. We're using one part >>>>>that's pin strappable for 8-4-2-1 MHz. >>>> >>>> A seven pin SOT-23? >>> >>>I think its this Linear part >>><http://cds.linear.com/docs/Datasheet/6900fa.pdf> >>>There are others tho. >> >>Neat (but sloppy - 1/5% to 2% error). That's a trinary input (1/10/100) in a >>SOT-23-5. John was suggesting 1-2-4-8 binary inputs. I've never seen a >>SOT-23-7. Up to six pins on a "SOT-23" I can understand, but where does the >>seventh pin go? > >Probably an SOT-23-8. Didn't know there was a SOT-23-8. I retract my question. ;-) >There are some 32-bit microcontrollers in 33 pin packages. The thermal >pad is the ONLY ground pin IIRC. Codecs, too. I hate QFNs. |