This tool converts from crystal oscillator stability in terms of Parts Per Million (PPM) to the equivalent Frequency variation (Hz/kHz/MHz/GHz)
Enter
- PPM value
- Center Frequency (use the dropdown menu to select units)
The tool will provide the frequency variation and min and max values of frequency
🔁 Frequency to PPM
Formula
The frequency variation df on either side of the center frequency F is given by
df = F*ppm*10-6
The maximum and minimum frequency are given by
Fmax = F + df
Fmin = F – df
Example Calculation
The following 10 MHz oscillator has a frequency stability of +/- 0.1 PPM
The oscillator can be used as a reference clock with a phase locked loop to generate a frequency of 1 GHz.
Enter these numbers (0.1 PPM and 1 GHz) into the calculator above to calculate a frequency variation of +/- 25 kHz. The minimum and maximum frequencies generated are 999.975 MHz and 1000.025 MHz, respectively.
What is PPM?
PPM, or parts per million, is a unit of measure used to describe small values of dimensionless quantities, such as the relative change in frequency or the concentration of a particular substance in a solution. In the context of frequency, PPM is used to describe the deviation or stability of a frequency source relative to its nominal value.
The Importance of PPM in Frequency Measurements
Frequency stability is essential in many applications, particularly in communications, where the accuracy of signal transmission and reception can critically impact performance. A frequency source might be specified with a stability of, for example, ±10 PPM, meaning it can vary by 10 parts per million from the nominal frequency. This variation can affect how systems synchronize or how accurately signals are modulated or demodulated.
Applications of PPM to Frequency Conversion
Understanding and applying PPM to frequency conversion is vital in several technical fields:
- Telecommunications: Ensures compatibility and synchronization in networks and communication systems.
- Broadcasting: Maintains frequency standards for clear and reliable transmission.
- Satellite Communications: Helps in precise navigation and data transmission.
- Scientific Instruments: Ensures accuracy in measurements and operations that depend on stable frequency references.