Soft dB SPM PLL User Guide User Manual
Page 6
SPM - PLL User’s Manual
6
1.5
PLL Performance
PLL Module Specifications
Input Range
+-10V
Output Range
+-10V (external 1/100 and 1/1000 attenuators provided)
Frequency Range
3.2 kHz to 75 kHz
Resonator Test Board
An active resonator board is included with the SPM controller for easy testing and
setup of the PLL module
PLL Output Signal Ranges
(Stand-Alone Operation)
Excitation Frequency:
+-2.85 mHz
to +-23.9 kHz
Excitation Amplitude:
+-1.19 µV
to +-10 V
Resonator Phase:
+-6.83 µDeg
to +-57.3 Deg
Resonator Amplitude:
+-1.19 µV
to +-10 V
Phase Controller
Bandwidth: 1kHz
Phase Controller
Bandwidth: 5Hz
Excitation Frequency
60mHz RMS
20µHz RMS
Resonator Phase
4mDeg RMS
200µDeg RMS
Amplitude Controller
Bandwidth: 7.5Hz
Amplitude Controller
Bandwidth: 1.5Hz
Excitation Amplitude
400µV RMS
50µV RMS
PLL Signal Noise Levels*
Resonator Amplitude
5µV RMS
2µV RMS
Phase/Amplitude (PAC)
Detector Bandwidth
100Hz to 10kHz. The bandwidth is automatically adjusted when the loop auto-set
function is used
Software Features
1) Resonator frequency sweep for automatic measurement of resonator
frequency characteristics
2) Loop-gain auto-set for amplitude and phase controllers. Gains are set
according to desired closed-loop bandwidth
3) In-circuit closed-loop step response measurement function validates the setup
of both controllers
4) Adjustable low-pass filter on PLL signals: Excitation amplitude/frequency and
Resonator phase/amplitude. These filters can be adjusted from 1.5 Hz to 16 kHz
or bypassed
5) Real time monitoring of all PLL signals.
6) Long term monitoring of PLL signals to assess the low frequency stability and
noise
Temperature Coefficient
TCXO Stability:
140 ppb over a temperature range from -20 °C to 70°C
TCXO Precision:
2 ppm
*
Note: Noise levels are measured using the resonator board included with the SPM controller (gain –13 dB at the
resonance) and the auto-set of loop gains for both controllers. The new PLL technique ensures that the noise levels are
independent of measurement ranges.