(Preliminary) Analog Frequency Multiplier

(Preliminary)
Analog Frequency Multiplier
PL565-78 for 491.52 MHz Wireless Base Station VCXO Family
PRODUCT DESCRIPTION
FEATURES
PhaseLink’s Analog Frequency Multiplier (AFM) is
the industry’s first ‘Balanced Oscillator’ utilizing
analog multiplication of the fundamental frequency
(at quadruple frequency), combined with an
attenuation of the fundamental of the reference
crystal, without the use of a phase-locked loop
(PLL), in CMOS technology.
•
•
•
•
•
PhaseLink’s world’s best performing AFM products
can achieve up to 800 MHz output frequency with
little jitter or phase noise deterioration.
•
•
•
•
•
•
•
PL565-78, however, is custom designed to meet the
stringent phase noise requirements of wireless base
station applications, operating at 491.52 MHz.
Non-PLL frequency multiplication by 4.
Input frequency: 122.88 MHz
Output frequency: 491.52 MHz
Low phase noise and jitter (equivalent to fundamental
crystal at the output frequency)
Ultra-low jitter
o RMS phase jitter < 100 fs (12kHz-20MHz)
o RMS random period jitter < 2 ps
Low phase noise
o -65 dBc/Hz @10Hz offset from the carrier
o -96 dBc/Hz @100Hz offset from the carrier
High linearity pull range (typ. 5%)
VCXO, set pullability ±100ppm ~ ±150ppm
Differential output levels: LVPECL
Single 3.3V, ±10% power supply
Operating temperature range: -40°C to +85°C
Available in 3x3mm QFN-16L package.
PL565-78 Block Diagram
L2X
VCON
OE
X IN
O s c illa to r
A m p lifie r
XOUT
F re q u e n c y
X2
F re q u e n c y
X4
QBAR
Q
L4X
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 1
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
Name
R-BIAS
GNDOSC
VCON
XIN
XOUT
OE
L4X
VDDOSC
GNDBUF
PECL
PECLB
VDDBUF
VDDANA
OESEL
VDDOSC
L2X
15
L2X
16
QFN
Pin #
Type
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
I
P
I
I
O
I
I
P
P
O
O
P
P
I
P
I
GNDBUF
PECL
10
9
P565565-78
1
2
3
4
XIN
VDDOSC
11
VCON
14
PECLB
OESEL
12
GNDOSC
13
R-BIAS
VDDANA
VDDBUF
PIN ASSIGNMENT AND DESCRIPTION
8
VDDOSC
7
L4X
6
OE
5
XOUT
Description
External bias resistor connection
GND connection
Control voltage input
Crystal Input pad
Crystal Output pad
Output Enable input
External inductor connection
VDD connection
GND connection
LVPECL output
LVPECL complementary output
VDD connection
VDD connection
OE style selection pin
VDD connection
External inductor connection
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 2
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
AFM Phase Noise at 491.52MHz, using 122.88MHz crystal
AFM Spectrum at 491.52MHz, using 122.88MHz crystal
The analog frequency multiplication preserves the low phase noise of the quartz crystal oscillator while keeping
unwanted sub harmonics from the multiplication at very low levels. Sub harmonics appear only at large distance
from the carrier, far outside the loop bandwidth of a PLL that uses the AFM signal to multiply up further to a
multiple GHz network clock. This means the impact of the sub harmonics on the application is negligible.
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 3
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
PHASE NOISE PERFORMANCE
Part
Number
Input
Freq.
(MHz)
Output
Freq.
(MHz)
Phase Noise at Frequency Offset From Carrier (dBc/Hz)
10Hz
PL565-78
122.88
491.52
-64
Phase noise was measured using Agilent E5052B.
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
-96
-123
-135
-141
-150
-155
Phase
Jitter
12KHz ~
20MHz
(ps)
0.05
SUB-HARMONIC PERFORMANCE
Output
Input
Part
Frequency Frequency
Number
(MHz)
(MHz)
Spectral Specifications / Sub-harmonic Content (dBc), Freq. (MHz)
@
-75%(Fc)
@
-50%(Fc)
-60
-40
PL565-78
122.88
491.52
Note: Spectral specifications were obtained using Agilent E7401A
@
-25%(Fc)
-70
@
@
@
+25%(Fc) +50%(Fc) +75%(Fc)
-70
-40
-70
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 only one
inductor per squarer is adequate for excellent performance.
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 4
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
APPLICATION CIRCUIT
RECOMMENDED PCB LAYOUT
•
Avoid ground planes underneath the crystal
and inductor traces to limit parasitic
capacitance.
•
Add bypass capacitor close to VDDBUF pin.
•
Avoid bypass capacitors near VDDOSC pins to
lower cross-talk of unwanted frequencies.
•
L1X(a,b) can be used to increase the VCXO
pulling range. Using ferrite core inductors limits
the oscillation amplitude which can have a
positive effect on phase noise.
•
L2X and L4X tune the frequency multiplier tank
circuits. They need to be wire wound inductors
with high Q-factor, preferably >20.
•
The large center pad is the “thermal relief” pad
and can be connected to ground.
TYPICAL COMPONENT VALUES FOR 491.52MHz OPERATION:
L1Xa = L1Xb = 100nH for typical +140/-130ppm Frequency Pulling with Crystal C1=6fF and C0=2pF
L2X = 36 nH , Coilcraft 0402CS or 0402HP
L4X = 9.5 nH , Coilcraft 0402CS or 0402HP
R-BIAS = 300 Ω
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 5
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
INDUCTOR VALUE OPTIMIZATION
The required inductor values for the best performance depend on the operating frequency, and the board layout
or module specifications. The listed values in this datasheet are based on the calculated parasitic values from
PhaseLink’s evaluation board design. These inductor values provide the user with a starting point to determine
the optimum inductor values. Additional fine-tuning may be required to determine the optimal solution.
The inductor is recommended to be a high Q small size 0402 or 0603 SMD component, and must be placed
between L2X / L4X and adjacent VDDOSC pin. Place inductor as close to the IC as possible to minimize parasitic
effects and to maintain inductor Q.
To assist with the inductor value optimization, PhaseLink has developed AFM “Tuning Assistant” documents. You
can download these documents from PhaseLink’s web site (www.phaselink.com). The documents consist of
tables with recommended inductor values for certain output frequency ranges.
Figure 10: Diagram Representation of the Related System Inductance and Capacitance
DIE SIDE
- Cinternal at L2X = 7.625 pF , at L4X = 6.25 pF
- Cpad = 1.0 pF, Bond pad and its ESD circuitry
- C11 = 0.4 pF, The following amplifier stage
PCB side
- LWB1 = 2 nH, (2 places), Stray inductance
- Cstray = 0.5 pF, Stray capacitance
- L2X (L4X) = 2x or 4x inductor
- C2X (C4X) = range (0.1 to 2.7 pF), Fine tune
the tank, if used.
Work out the resonance of this network and you have a good first guess for the required inductor values for
optimum performance. Non-linear behavior at large signal amplitudes can shift the tank resonance significantly,
especially at the L2X side, to a lower frequency than the calculation suggests. The Tuning Assistant documents
are based upon actual lab tests and are corrected for the non-linear behavior.
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 6
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
ELECTRICAL SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
PARAMETERS
SYMBOL
Supply Voltage
MIN.
V DD
MAX.
UNITS
4.6
V
Input Voltage, DC
VI
GND-0.5
V DD +0.5
V
Output Voltage, DC
VO
GND-0.5
V DD +0.5
V
Storage Temperature
TS
-65
150
°C
Ambient Operating Temperature, Industrial
T A_I
-40
+85
°C
Ambient Operating Temperature, Commercial
T A_C
0
+70
°C
125
°C
260
°C
2
kV
Junction Temperature
TJ
Lead Temperature (soldering, 10s)
Input Static Discharge Voltage Protection (HBM)
Exposure of the device under conditions beyond the limits specified by Maximum Ratings for extended periods may cause permanent damage to the
device and affect product reliability. These conditions represent a stress rating only, and functional operations of the device at these or any other
conditions above the operational limits noted in this specification is not implied .
VOLTAGE CONTROL SPECIFICATION
PARAMETERS
VCXO Stabilization Time
SYMBOL
T VCXOSTB
CONDITIONS
MIN.
From power valid
VCXO Tuning Range*
XTAL C 0 /C 1 <300
200
CLK Output Pullability*
VCON= 1.65V, ± 1.65V
XTAL C 0 /C 1 <300
±100
Linearity
UNITS
10
ms
ppm
±120
130
0V < VCON < 3.3V, -3dB
MAX.
ppm
5
VCON Input Impedance
VCON Modulation BW
TYP.
10
%
kΩ
40
kHz
* Note: The VCXO Tuning Range and Pullability can be controlled with the value for inductor L1X. See Tuning Assistant document for a
guide to chose the L1X value based upon crystal frequency and motional parameters.
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 7
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
LVPECL ELECTRICAL CHARACTERISTICS
PARAMETERS
SYMBOL
CONDITIONS
Supply Current, loaded outputs
I DD
Fout = 491.52MHz
Operating Voltage
V DD
MIN.
TYP.
MAX.
UNITS
75
80
mA
3.63
V
55
%
2.97
Output Clock Duty Cycle
@V DD –1.3V
45
50
Short Circuit Current
mA
±50
Output High Voltage
V OH
Output Low Voltage
V OL
R L = 50Ω to
(V DD – 2V)
Clock Rise Time
tr
@ 20/80%
Clock Fall Time
tf
@ 80/20%
LVPECL Levels Test Circuit
V DD -1.025
V
V DD -1.620
V
0.25
0.45
ns
0.25
0.45
ns
LVPECL Transistion Time Waveform
DUTY CYCLE
OUT
VDD
50?
2.0V
45 - 55%
55 - 45%
OUT
80%
50%
50?
20%
OUT
OUT
tR
tF
OE LOGIC SELECTION
OESEL
0 (Default)
1
OE
Output State
0 (Default)
Enabled
1
Tri-state
0
Tri-state
1 (Default)
Enabled
0 (Default): Connect to GND or leave floating to set to “0”. Internal pull-down.
1 (Default): Connect to VDD or leave floating to set to “1”. Internal pull-up.
0: Connect to GND to set to “0”. 1: Connect to VDD to set to “1”.
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 8
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
PACKAGE INFORMATION
QFN-16L
Max
A
0.70
0.75
0.80
A1
0.00
-
0.05
D1
DED
Nom
0.20
A3
b
0.20
0.25
0.30
D
2.95
3.00
3.05
E
2.95
3.00
3.05
D1
1.65
1.70
1.75
E1
1.65
1.70
1.75
L
0.250
0.300
0.350
e
L
Dimension (mm)
Min
DDD
E1
Symbol
e
Pin1 Dot
b
A
A3
0.50BSC
SEATING
PLANE
A1
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 9
(Preliminary)
Analog Frequency Multiplier
PL565-78 AFM VCXO
ORDERING INFORMATION
For part ordering, please contact our Sales Department:
2880 Zanker Rd., San Jose, CA 95134, USA
Tel: (408) 571-1668 Fax: (408) 571-1688
PART NUMBER
The order number for this device is a combination of the following:
Part number, Package type and Operating temperature range
PL565-78 X X X
PART NUMBER
R= TAPE AND REEL
PACKAGE TYPE
Q= QFN
TEMPERATURE
C=COMMERCIAL
Order Number
PL565-78QC
Marking
P565
78
LLL
Package Option*
QFN – Tape & Reel
*Note: LLL represent the production lot number
PhaseLink Corporation, reserves the right to make changes in its products or specifications, or both at any time without notice. The information
furnished by Phaselink is believed to be accurate and reliable. However, PhaseLink makes no guarantee or warranty concerning the accuracy of said
information and shall not be responsible for any loss or damage of whatever nature resulting from the use of, or reliance upon this product.
LIFE SUPPORT POLICY: PhaseLink’s products are not authorized for use as critical components in life support devices or systems without the
express written approval of the President of PhaseLink Corporation.
2880 Zanker Rd., San Jose, California 95134 Tel (408) 571-1668 Fax (408) 571-1688 www.phaselink.com Rev 9/2/11 Page 10