NF corporation

Lecture for Measurement

Posted 26/02/2020

DC Power Supply (AC-DC Power Supply)

Examples of Improved Measurement and Evaluation by Using a Low-noise DC Power Supply

2. Stability Improvement of Voltage-controlled Crystal Oscillator

For voltage-controlled high-precision devices, such as crystal oscillators, the noise and stability of the control voltage affect directly to the performance of the device.
For product inspection and evaluation of such voltage-controlled devices, it is important to use a low-noise and highly stable voltage source.
Measured how much the noise of control voltage source affects the output with the measurement system shown in Figure 3.

Figure 3: Evaluation system for output frequency of a voltage controlled crystal oscillator.

TCVCXO center frequency: about 30 MHz; measurement period: 1 Hz; number of measurements: 40,000; total measurement time: about 11 hours; ambient temperature: 23 ±5°C.

As shown in Figure 4, when using our low-noise power supply LP5394, the variation of output frequency is lower than half comparing when using a general linear regulator type power supply.

Thus, even if the device is same, the quality of the power supply causes a difference in the variation of output frequency.
Therefore, it is necessary to pay attention to the quality of the power supply when evaluating the devices which requires voltage-control.

Figure 4: Difference due to control voltage source for TCVCXO output frequency variation.

Prev page: Improvement of S/N Ratio of Photodiode Output

Related Product

Low-noise DC Voltage Source LP6016-01/P

Bias-voltage and control-voltage source for sensors and devices.

Low noise: 10 µV/√Hz (Bandwidth: 10 Hz to 20 MHz)
High stability: ±10 ppm/°C
Setting accuracy: ±(0.03%+250µ V)
Output voltage: 0 to +16.1 V (LP6016-01)
0 to +16.1 V x 2ch (LP6016-01P)
Output current: 100 mA
External control interface: USB, RS-232, LAN

Details

Related keywords : Low Noise DC Voltage Source