CD4521 DATASHEET PDF
CD Datasheet, CD Stage Frequency Divider Datasheet, buy CD Data sheet acquired from Harris Semiconductor. SCHS Page 2. Page 3. Page 4. Page 5. Page 6. Page 7. Page 8. IMPORTANT NOTICE. Texas Instruments. all relevant TOSHIBA information, including without limitation, this document, the specifications, the data sheets and application notes.
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I have a peculiar problem involving the CD frequency divider of which I use two in a redundant configuration as shown cd451 my schematic snippet below: Another solution is a If the code is adjusted for the particular RC oscillator on chip, the accuracy can be very very good and be stable at room temperature too with only a tiny variation for plus and minus say 10 degrees C.
Below is the relevant part of my PCB layout – your wisdom will be much appreciated! Not everyone likes or wants to use microcontrollers and i understand this, so another solution is to use an LM and a capacitor and a few resistors to make a 1Hz oscillator. Or you can use an external source. It’s a very fatasheet circuit and is not too sensitive to voltage variations, and accuracy can be adjusted to very very close to perfect if you have a frequency counter available.
Boncuk New Member May 18, Could I just not purchase an oscillator? Again, kudos to brhans for spotting the problem first. Electro Tech is an online community with overmembers who enjoy talking about and building electronic circuits, projects and gadgets. I agree and would like to use your suggested circuit. Slightly clearer internal logic diagrams datasheeg the IC are available in the datasheets from: Could you please post the component values?
I have to admit that I like that crusty old scan quite a bit. Is this a different ? Just saying hello Started by MichaelaJoy Yesterday at 6: You shouldn’t be grounding it. Also, as I mentioned, these ICs might already have been partially damaged, and require replacement if you want to be confident of their future behaviour and reliability.
I do have a good scope once I learn to use it. I do want one pulse per second. It cdd4521 normal to leave unused outputs unconnected, not connect them to Gnd. The Maxim part is expensive because it is Temperature Compensated, so it has circuitry that is probably individually calibrated at several temperatures.
I have a peculiar problem involving the CD frequency divider of which Datqsheet use two in a redundant configuration as shown in dtaasheet schematic snippet below:. Hi there Jack, I would like to ask you an important question, but i’ll save that for later. The difference is, if the oscillator is going to be used as a 1Hz time base for say a frequency counter, the frequency really needs to be one half Hertz, not 1Hz, because the period of time the 1Hz wave is high is only one have second and they really want 1 full second.
Thread starter jack Start date May 17, Maybe they did not update their datasheet. I was thinking the cd421 may not be accurate enough and failed to realize that it could simply serve as a counter running off a crystal. I’ve edited the original image from the TI datasheet that you linked, to datashset extraneous parts. Calibrate with that maybe? One Second Time Base. That’s cheap and low power compared to a Rubidium oscillator.
One Second Time Base
Media New media New comments Search media. I wasn’t born with CD-series logic in hand so maybe I’m missing out something obvious Can I use the 3 volt type in a five volt circuit? With a 12F and a Hz watch crystal you could have a pretty accurate 1Hz timebase. The simplist way I know of is to use a CD and a 4. Ok, now for the important question: Since the logic Low driven on pin 7 is not exactly zero volts, there will be datasgeet extra unplanned current from pin 7 to Gnd.
Also, I varnished over the cut with nail polish to prevent accidental contact due to oxide growth.
Home Questions Tags Users Unanswered. No, it’s 2Hz only, to get 1Hz you need another divider. Then i have to ask, why the problem?