PicoEMI Programmable Spread Spectrum Clock

(Preliminary)
PicoEMI T M Programmable Spread Spectrum Clock
FEATURES
PIN CONFIGURATION
 Accepts Crystal or Reference Clock input
o Crystal: 10MHz - 40MHz
o Reference Clock: 1MHz - 200MHz
 Output Frequency up to 200MHz
 Center and Down Spread Spectrum Modulation
 Two selectable pre-programmed configurations
 Max 100ps Cycle to Cycle jitter
 Single 2.5V ~ 3.3V, ± 10% power supply
 Operating temperature range from -40C to 85C
 Available in SOP-8L GREEN/RoHS compliant
package
XIN/FIN
1
8
XOUT
GND
2
7
VDD
CSEL^
3
6
PDB^
CLK0
4
5
REFOUT
SOP-8L
Note: ^ Denotes 60KΩ Pull-up resistor
DESCRIPTION
The PL671-23 is a high performance programmable spread spectrum clock. It allows for programming the
modulation type (Center or Down Spread) and 16 modulation magnitudes (±0.125% to ±2.0% or -0.25% to -4.0%).
The CSEL pin can switch between two pre-programmed configurations adding to the flexibility.
CSEL
0
1
Input
(MHz)
Spread
Spectrum Type
Spread Spectrum
Modulation Amplitude
Output
(MHz)
10 – 40 (Xtal)
1 – 200 (REF)
Configurable as
Center or Down
Configurable as
Center: ±0.125% to ±2.0%
Down: -0.25% to -4.0%
1 – 200
(Programmable Multiplier)
BLOCK DIAGRAM
REFOUT
SS
Modulation
XIN/FIN
XOUT
Xtal
Osc
RCounter
Phase
Detector
CSEL
Charge
Pump
Loop
Filter
VCO
MCounter
PDB
CLK0
Built-in Crystal load Capacitors
No external caps are required
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991 www.phaselink.com Rev 07/24/09 Page 1
(Preliminary)
PicoEMI T M Programmable Spread Spectrum Clock
PACKAGE PIN ASSIGNMENT
Name
SOP-8L
Type
Description
XIN/FIN
1
I
Crystal or Reference input pin
GND
2
P
CSEL
3
I
CLK0
4
O
GND connection
Selector pin used to toggle between two pre-programmed configurations.
This pin has a 60KΩ internal pull up resistor. There are two possible predefined configurations can be chosen from the following combination.
- Spread Spectrum modulation Type (Center or Down)
- Spread Spectrum modulation Amplitude
Center Spread - ±0.125% to ±2.0% in ±0.125% steps
Down Spread - -0.25% to -4.0% in 0.25% steps)
- Output Clock Drive Strength (4mA, 8mA, 16mA)
Spread Spectrum Clock Output
REFOUT
5
O
Reference Output. Equal to the input frequency, no spread spectrum
PDB
6
I
Power Down input. 60kΩ internal pull up, default High (1)
VDD
7
P
VDD connection (2.25~3.63V)
XOUT
8
O
Crystal output pin. Do Not Connect when using FIN.
LAYOUT RECOMMENDATIONS
The following guidelines are to assist you with a performance optimized PCB design:
Signal Integrity and Termination
Considerations
Decoupling and Power Supply
Considerations
- Keep traces as short as possible.
- Place decoupling capacitors as close as possible to
the VDD pin(s) to limit noise from the power supply
- Trace = Inductor. With a capacitive load this
equals ringing!
- Long trace = Transmission Line. Without proper
termination this will cause reflections ( looks like
ringing ).
- Design long traces (>1 inch) as “striplines” or
“microstrips” with defined impedance.
- Match trace at one side to avoid reflections
bouncing back and forth.
- Multiple VDD pins should be decoupled separately
for best performance.
- Addition of a ferrite bead in series with VDD can
help prevent noise from other board sources
- Value of decoupling capacitor is frequency
dependant. Typical values to use are 0.1F for
designs using frequencies < 50MHz and 0.01F for
designs using frequencies > 50MHz.
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991 www.phaselink.com Rev 07/24/09 Page 2
(Preliminary)
PicoEMI T M Programmable Spread Spectrum Clock
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991 www.phaselink.com Rev 07/24/09 Page 3
(Preliminary)
PicoEMI T M Programmable Spread Spectrum Clock
ELECTRICAL SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
PARAMETERS
SYMBOL
MIN.
MAX.
UNITS
V DD
-0.5
4.6
V
Input Voltage Range
VI
-0.5
V DD +0.5
V
Output Voltage Range
VO
-0.5
V DD +0.5
V
260
C
Supply Voltage Range
Soldering Temperature (Green package)
10
Data Retention @ 85C
Storage Temperature
TS
Ambient Operating Temperature*
Year
-65
150
C
-40
85
C
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. *Operating temperature is guaranteed by design. Parts are tested to commercial grade only.
AC SPECIFICATIONS
PARAMETERS
Crystal Input Frequency(XIN)
Input (FIN) Frequency
Input (FIN) Signal Amplitude
Input (FIN) Signal Amplitude
Output Frequency
CONDITIONS
Fundamental Crystal
@ V DD =3.3V
@ V DD =2.5V
Internally AC coupled (High Frequency)
MIN.
TYP.
10
MAX.
UNITS
40
MHz
200
1
166
MHz
0.9
V DD
Vpp
0.1
V DD
Vpp
@ V DD =3.3V
200
MHz
@ V DD =2.5V
166
MHz
Internally AC coupled (Low Frequency)
3.3V <50MHz, 2.5V <40MHz
Settling Time
At power-up (after V DD increases over
2.25V)
2
ms
Output Enable Time
PDB Function; Ta=25º C, 15pF Load
2
ms
Output Rise Time
Output Fall Time
15pF Load, 10/90% V DD , Standard Drive
2.0
3.0
ns
15pF Load, 10/90% V DD , High Drive
1.2
1.7
ns
15pF Load, 90/10% V DD , Standard Drive
2.0
3.0
ns
15pF Load, 90/10% V DD , High Drive
1.2
1.7
ns
50
55
%
100
ps
Duty Cycle
At V DD /2
Cycle to Cycle Jitter*
T CYC - CYC Over output frequency range @
3.3V
45
* Note: Jitter performance depends on the programming parameters.
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991 www.phaselink.com Rev 07/24/09 Page 4
(Preliminary)
PicoEMI T M Programmable Spread Spectrum Clock
DC SPECIFICATIONS
PARAMETERS
SYMBOL
Supply Current, Dynamic, with
Loaded Outputs
I DD
CONDITIONS
MIN.
TYP.
MAX.
UNITS
At 25MHz, 3.3V,
load=15pF, (PDB=1)
15
mA
PDB=0 [with reference
10
A
3.63
V
0.4
V
input pin (FIN) pulled down]
Operating Voltage
V DD
2.25
Output Low Voltage
V OL
I OL = +4mA (Std. Drive)
Output High Voltage
V OH
I OH = -4mA (Std. Drive)
V DD – 0.4
V
Output Current, Low Drive
I OSD
V OL = 0.4V, V OH = 2.4V
4
mA
Output Current, Standard Drive
I OSD
V OL = 0.4V, V OH = 2.4V
8
mA
Output Current, High Drive
I OHD
V OL = 0.4V, V OH = 2.4V
16
mA
CRYSTAL SPECIFICATIONS
PARAMETERS
Fundamental Crystal Resonator Frequency
Crystal Loading Rating
SYMBOL
MIN.
F XIN
10
TYP.
C L (xtal)
40
MHz
pF
100
Operating Drive Level
Small SMD Crystal
UNITS
15
Maximum Sustainable Drive Level
Metal Can Crystal
MAX.
W
30
Shunt Capacitance
ESR Max
C0
5.5
pF
ESR
50
Ω
C0
2.5
pF
ESR
80
Ω
Shunt Capacitance
ESR Max
W
PACKAGE DRAWINGS (GREEN PACKAGE COMPLIANT)
SOP-8L
Symbol
A
A1
A2
B
C
D
E
H
L
e
Dimension in MM
Min.
Max.
1.35
1.75
0.10
0.25
1.25
1.50
0.33
0.53
0.19
0.27
4.80
5.00
3.80
4.00
5.80
6.20
0.40
0.89
1.27 BSC
E
H
D
A2 A
A1
C
e
b
L
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991 www.phaselink.com Rev 07/24/09 Page 5
(Preliminary)
PicoEMI T M Programmable Spread Spectrum Clock
ORDERING INFORMATION (GREEN PACKAGE COMPLIANT)
For part ordering, please contact our Sales Department:
47745 Fremont Blvd., Fremont, CA 94538, USA
Tel: (510) 492-0990 Fax: (510) 492-0991
PART NUMBER
The order number for this device is a combination of the following:
Part Number, Package Type and Operating Temperature Range
PL671-23-XXX
X X-R
PART NUMBER
NONE= TUBE
R=TAPE and REEL
3 DIGIT ID Code *
PACKAGE TYPE
S=SOP-8L
TEMPERATURE
C=COMMERCIAL (0°C to 70°C)
I = INDUSTRIAL (-40°C to 85°C)
* PhaseLink will assign a unique 3-digit ID code for each approved programmed part number.
Part/Order Number
PL671-23-XXXSC
PL671-23-XXXSC-R
†
Marking†
P671-23
XXX
P671-23
XXX
Package Option
8-Pin SOP (Tube)
8-Pin SOP (Tape and Reel)
Note: ‘XXX’ designates marking identifier that, at times, could be independent of the part number.
Please consult your PhaseLink sales representative for marking information.
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.
Solder reflow profile available at www.phaselink.com/QA/solderingGreen.pdf
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991 www.phaselink.com Rev 07/24/09 Page 6