PL560-08_12 Datasheet, PDF (4/12 Pages) Micrel Semiconductor – Analog Frequency Multiplier

(Preliminary) Analog Frequency Multiplier
PL560/565-08 VCXO Family
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
PL560-08 62.5 - 150 250 - 600 491.52 -64 -96 -123 -135 -141 -150 -155
PL565-08 150 - 200 600 - 800 622.08
Phase noise was measured using Agilent E5052B.
-56 -87 -113 -134 -143 -149 -153
Phase
Jitter
12KHz ~
20MHz
(ps)
0.05
0.04
SUB-HARMONIC PERFORMANCE
Part
Number
Input
Output
Frequency Frequency
(MHz)
(MHz)
Spectral Specifications / Sub-harmonic Content (dBc), Freq. (MHz)
Carrier
Freq.
(Fc)
@
-75%
(Fc)
@
-50%
(Fc)
@
-25%
(Fc)
@
+25%
(Fc)
@
+50%
(Fc)
@
+75%
(Fc)
PL560-08
122.88
491.52
491.52
-60
-40
-70
-70
-40
-70
PL565-08
155.52
622.08
622.08
-60
-40
-40
-40
-40
-50
Note: Spectral specifications were obtained using 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 sine 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 o nly 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 6/22/11 Page 4