Parts Per Million Frequency Error
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or Generation Accuracy Hardware: Multifunction DAQ (MIO), Digital I/O (DIO), Counter/Timers (TIO), Modular Instruments>>Dynamic Signal Acquisition and ppm error calculator Analysis (DSA)>>PXI-4462, Modular Instruments>>Dynamic Signal Acquisition and Analysis (DSA)>>PXIe-4497,
Frequency Stability Ppm Definition
Modular Instruments>>Dynamic Signal Acquisition and Analysis (DSA)>>PXIe-4496, Modular Instruments>>Dynamic Signal Acquisition and Analysis (DSA)>>PXIe-4492, ppm accuracy definition Modular Instruments>>Dynamic Signal Acquisition and Analysis (DSA)>>PXIe-4499, Modular Instruments>>Dynamic Signal Acquisition and Analysis (DSA)>>PXI-4461, Modular Instruments>>Dynamic Signal Acquisition and Analysis (DSA)>>PXIe-4498 Problem: How ppm to seconds can I determine frequency error and frequency measurement or generation accuracy? Solution: Frequency accuracy (sometimes called timing accuracy) is usually given in parts per million (ppm) of the sample rate. This value depends on the device that you are using and can be found in the device's
What Is Frequency Error
specifications. In addition to frequency accuracy (fa), frequency error (fe) is also something that you can calculate, using the equations below:Measured frequency (fm) = signal frequency (fs) ± frequency error (fe). Rearranging the above equation to solve for frequency error: Frequency error (fe) = signal frequency (fs) * frequency accuracy (fa). Examples:Consider a case in which you are measuring a precise 100kHz sine wave, using a device with a frequency accuracy of 25 ppm. The frequency error will be 100,000Hz * 25/1,000,000 = 2.5Hz. Therefore, the frequency accuracy is 100kHz ± 2.5Hz.Consider a case in which you are generating a 1kHz sine wave, using a device with a frequency accuracy of 50 ppm. The frequency error will be 1,000Hz * 50/1,000,000 = 50mHz. Therefore, the frequency accuracy is 1kHz ± 50mHz. Related Links: KnowledgeBase 1F5DD5KD: What I
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Ppm To Frequency Nmr
Users Badges Unanswered Ask Question _ Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. Join them; it only takes http://digital.ni.com/public.nsf/allkb/2A0B9D3F365DEDEF86256BDB007354ED a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top What is the ppm in the crystal oscillator? up vote 15 down vote favorite 6 I'm a student and I'm working on a low power communication project. I am trying to design http://electronics.stackexchange.com/questions/15851/what-is-the-ppm-in-the-crystal-oscillator a PCB using the TI CC2540 sample design. There is a MC-306 (32.768kHz, 12.5pf, and 20/50ppm). I don't know what the 20/50ppm rating is. For me, the size is very important, so I decided to replace it with the FX135A, but its ppm is -20/+20. Will it cause a problem if I use this one instead? What is the ppm rating in the crystal oscillator? oscillator share|improve this question edited Aug 9 '14 at 13:37 Ricardo 3,898102956 asked Jun 23 '11 at 13:16 OHLÁLÁ 4432716 add a comment| 2 Answers 2 active oldest votes up vote 24 down vote accepted Like Olin said, ppm stands for parts per million, and it indicates how much your crystal's frequency may deviate from the nominal value. The MC-306 exists in a 20 ppm and a 50 ppm version. For the 20 ppm version this means that the frequency will be between 32.7673 kHz (32.768 - 20 ppm, or x 0.999980) and 32.7687 kHz (32.768 + 20 ppm, or x 1.000020). These numbers may give you a comfortable feeling, but rem
& Techniques PIC Tutorials Microcontroller Blog Site map. PIC C Course - 25% Off 18F Training Become a subscriber (Free) Join 29,000 other subscribers to receive subscriber sale discounts and other free resources. Name: E-Mail: Don't worry -- your e-mail address http://www.best-microcontroller-projects.com/ppm.html is totally secure. I promise to use it only to send you MicroZine. Clock accuracy in ppm Crystal Clock accuracy is defined in terms of ppm or parts per million and it gives a convenient way of comparing accuracies of different crystal specifications. Note: ppm parts per million. ppb parts per billion. The following headings give practical calculations showing the typical errors you will encounter when using a clock of a specific type frequency error with a specific accuracy. How good is a 1% accurate clock ? If you look at a day's worth of timekeeping then you have 24 x 60 x 60 = 86400 seconds in a day. So the maximum error after a day has passed is 1% of 86400 = 864 seconds = 14.4 minutes! Error: 14.4 minutes error per day. How good is a typical crystal ? A typical crystal has an error of 100ppm (ish) parts per million this translates as 100/1e6 or (1e-4) So the total error on a day is 86400 x 1e-4= 8.64 seconds per day. In a month you would loose 30x8.64 = 259 seconds or 4.32 minutes per month. Error: 8.64 seconds per day How good is a watch crystal ? A watch crystal has an error of 20ppm (ish), but you have to design the board layout well, this translates as 20/1e6 (2e-5) which gives an error over a day of 86400 * 2e-5 = 1.73 seconds per day so in a month it looses 30x1.72 = 51 seconds or 1 minute a month (approx). Error: 1.73 seconds per day. One of the other factors in a wrist watch is that you wear it on your wrist - and the human body is at a constant temperature. Crystals have a temperature coefficient graph meaning that another source of error is temperature (This is why you can buy an OCXO or Oven Controlled Crystal Oscillator - that generates heat and keeps a constant temperature). The watch crystal will be better because you keep it at a constant temperature! How good is an oven controller crystal oscillator OCXO ? A typical spec might be ±1 x 10-9 (1ppb) so the error after a day would be 86.4us and after a month 2.6ms (2.6e-3 seconds or 2.6 thousandths of a second!).