PL565-68 Datasheet, PDF (4/12 Pages) Micrel Semiconductor – Analog Frequency Multiplier

(Preliminary) Analog Frequency Multiplier
PL565-68 VCXO
PHASE NOISE PERFORMANCE
Part
Number
Input
Freq.
Range
(MHz)
Output
Freq.
Range
(MHz)
Phase Noise at Frequency Offset From Carrier (dBc/Hz)
Carrier
Freq.
(MHz)
10 100 1 10 100 1 10
Hz Hz kHz kHz kHz MHz MHz
PL565-68 62.5 - 160 125 - 320 311.04 -59 -93 -122 -137 -143 -149 -155
Phase noise was measured using Agilent E5052B.
Phase
Jitter
12KHz ~
20MHz
(ps)
0.07
SUB-HARMONIC PERFORMANCE
Part
Number
Input
Output
Frequency Frequency
(MHz)
(MHz)
Spectral Specifications / Sub-harmonic Content (dBc), Freq. (MHz)
Carrier Frequency
(Fc)
@ -50%
(Fc)
@ +50%
(Fc)
PL565-68
155.52
311.04
311.04
-60
-60
Note: Spectral specifications were obtained usin g Agilent E7401A
AFM MULTIPLYING TECHNIQUE
The analog frequency multiplication is achieved through a “squaring” operation.
The math is as follows: SIN²(x) = 0.5 - 0.5×COS(2x)
A very important property of this processing is that the result is a pure sin e wave with double frequency. In theory
there are no sub harmonics but in practice the squaring operation is not perfect and a low level of sub harmonics
is present anyway. The key is that the resulting sub harmonics are very low and simple filtering with only one
inductor per squarer is adequate for excellent performance.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax [phone] • www.micrel.com Rev 12/08/11 Page 4