ALSC I2811A-08TR Low-power emi reduction ic Datasheet

P2811/12/14
October 2003
rev
Low-Power EMI Reduction IC
Features
Deviation and Spread Option Selections section). These
combinations include Down Spread, Center Spread and
percentage deviation range from ±0.625% to -3.50%.
ƒ
FCC approved method of EMI attenuation
ƒ
Provides up to 15 dB EMI reduction
ƒ
Generates 1X, 2X, and 4X low EMI spread spectrum
ƒ
1X: P2811, 2X: P2812, 4X: P2814
ƒ
Optimized for input frequency range from 10 to 40
clock of the input frequency
MHz P2811: 10 to 40 MHz P2812: 10 to 40 MHz
P2814: 10 to 40 MHz
ƒ
Internal loop filter minimizes external components
and board space
ƒ
Selectable spread options: Down Spread and Center
Spread
Low inherent cycle-to-cycle jitter
ƒ
Eight spread % selections: ±0.625% to –3.5%
ƒ
3.3 V operating voltage
ƒ
CMOS/TTL compatible inputs and outputs
ƒ
Pinout
with
Cypress
The P28xx modulates the output of a single PLL in order to
“spread” the bandwidth of a synthesized clock, thereby
decreasing the peak amplitudes of its harmonics. This
results in significantly lower system EMI compared to the
ƒ
compatible
The P28xx reduces electromagnetic interference (EMI) at
the clock source, allowing a system wide EMI reduction for
all the down stream clocks and data dependent signals.
The P28xx allows significant system cost savings by
reducing the number of circuit board layers, ferrite beads,
shielding, and other passive components that are
traditionally required to pass EMI regulations.
typical narrow band signal produced by oscillators and
most clock generators.
Lowering EMI by increasing a
signal’s bandwidth is called “spread spectrum clock
CY25811,
CY25812, and CY25814
ƒ
Products available for industrial temperature range
ƒ
Available in 8-pin SOIC and TSSOP
generation”.
The P28xx uses the most efficient and optimized
modulation
profile
approved
by
the
FCC
and
is
implemented by using a proprietary all-digital method.
Applications
Product Description
The P28xx is a versatile spread spectrum frequency
modulator designed specifically for input clock frequencies
from 10 to 40 MHz (see Input/Output Frequency Range
Selections). The P28xx can generate an EMI reduced clock
from crystal, ceramic resonator, or system clock. The
P28xx-A and P28xx-B offer various combinations of spread
options and percentage deviations (see Output Frequency
The P28xx is targeted towards EMI management for
memory interfaces in mobile graphic chipsets and highspeed digital applications such as PC peripheral devices,
consumer electronics, and embedded controller systems.
Block Diagram
Alliance Semiconductor
2575, Augustine Drive • Santa Clara, CA • Tel: 408.855.4900 • Fax: 408.855.4999 • www.alsc.com
Notice: The information in this document is subject to change without notice.
P2811/12/14
October 2003
rev
Pin Configuration
Pin Description
Pin#
1
Pin Name
XIN
Type
I
2
VSS
P
Ground Connection. Connect to system ground.
D_C
I
SRS
I
ModOut
O
FRS
I
7
VDD
P
Digital logic input used to select Down (LOW) or Center (HIGH) Spread
Options (see Output Frequency Deviation and Spread Option Selections).
This pin has an internal pull-up resistor.
Spread Range Selection. Digital logic input used to select frequency
deviation (see Output Frequency Deviation and Spread Option Selections).
This pin has an internal pull-up resistor.
Spread Spectrum clock output (see Input/Output Frequency Range
Selections and Output Frequency Deviation and Spread Option Selections).
Frequency Range Selection. Digital logic input used to select input frequency range (see Input/Output Frequency Range Selections). This pin has
an internal pull-up resistor.
Connect to +3.3 V
8
XOUT
I
Connect to crystal. No connect if externally generated clock signal is used.
3
4
5
6
Description
Connect to externally generated clock signal or crystal.
Input/Output Frequency Range Selections
P2811 (1X)
Input
Output
(MHz)
(MHz)
Part number
P2812 (2X)
Input
Output
(MHz)
(MHz)
P2814 (4X)
Input
Output
(MHz)
(MHz)
0
10-20
10-20
10-20
20-40
10-20
40-80
1
20-40
20-40
20-40
40-80
20-40
80-160
Pin 6
FRS
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
Modulation
rate
Input frequency
/ 448
Input frequency
/ 896
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Output Frequency Deviation and Spread Option Selections
Part number
Pin 3 D_C
Pin 4 SRS
0
0
Output frequency deviation and
spread option
-2.50% (Down)
0
1
-3.50% (Down)
1
0
+/-1.25% (Center)
1
1
+/-1.75% (Center)
0
0
-1.25% (Down)
0
1
-1.75% (Down)
1
0
+/-0.625% (Center)
1
1
+/-0.875% (Center)
P2811/12/14A
P2811/12/14B
Absolute Maximum Ratings
Symbol
VDD, VIN
TSTG
TA
Parameter
Voltage on any pin with respect to GND
Rating
Unit
-0.5 to + 7.0
V
Storage temperature
-65 to +125
°C
0 to 70
°C
Operating temperature
DC Electrical Characteristics
3.3 V, 25° C
Symbol
Parameter
VIL
Input Low Voltage
VIH
Input High Voltage
Input low Current (inputs
D_C, SRS, and FRS)
Input High Current
XOUT Output Low Current
(@ 0.4V, VDD = 3.3V)
XOUT Output High Current
(@ 2.5V, VDD = 3.3V)
Output Low Voltage
(VDD=3.3V, IOL = 20 mA)
Output High Voltage
(VDD=3.3V, IOH = 20 mA)
Static Supply Current
Standby Mode
Dynamic Supply Current
Normal Mode (3.3V and 25
pF probe loading)
Operating Voltage
Power Up Time (First locked
clock cycle after power up)
Clock Output Impedance
IIL
IIH
IXOL
IXOH
VOL
VOH
IDD
ICC
VDD
tON
ZOUT
Min
Typ
Max
Unit
GND – 0.3
–
–
0.8
V
–
VDD + 0.3
V
-60.00
–
-20.00
µA
–
–
1.00
µA
2.00
–
12.00
mA
–
–
12.00
mA
–
–
0.4
V
–
–
2.8
V
–
4.5
–
mA
7.1 fIN-min
–
13.9 fIN-max
mA
–
3.3
–
V
–
0.18
–
mS
–
50
–
Ω
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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AC Electrical Characteristics
3.3 V, 25° C
Symbol
Parameter
fIN
Input frequency P2811/12/14
10
–
40
MHz
Output frequency P2811
10
–
40
MHz
Output frequency P2812
20
–
80
MHz
40
–
160
MHz
tJC
Output frequency P2814
Output rise time (measured at
0.8V to 2.0V)
Output fall time (measured at
2.0V to 0.8V)
Jitter (cycle to cycle)
tD
Output duty cycle
fOUT
tLH 1
tHL 1
Min
Typ
Max
Unit
0.69
ns
0.66
ns
-200
–
200
ps
45
50
55
%
1. tLH and tHL are measured into a capacitive load of 15 pF
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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Package Information
Mechanical Package Outline 8-Pin SOIC
Symbol
Dimensions in inches
Dimensions in millimeters
Min
Nor
Max
Min
Nor
Max
A
0.057
0.064
0.071
1.45
1.63
1.80
A1
0.004
0.007
0.010
0.10
0.18
0.25
A2
0.053
0.061
0.069
1.35
1.55
1.75
B
0.012
0.016
0.020
0.31
0.41
0.51
C
0.004
0.006
0.01
0.10
0.15
0.25
D
0.186
0.194
0.202
4.72
4.92
5.12
E
0.148
0.156
0.164
3.75
3.95
4.15
e
0.050 BSC
1.27 BSC
H
0.224
0.236
0.248
5.70
6.00
6.30
L
0.012
0.020
0.028
0.30
0.50
0.70
a
0°
5°
8°
0°
5°
8°
Note: Controlling dimensions are millimeters
SOIC – 0.074 grams unit weight
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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rev
Mechanical Package Outline 8-Pin TSSOP
Dimensions in inches
Symbol
Min
Nor
A
Max
Dimensions in millimeters
Min
Nor
0.047
A1
0.002
A2
0.031
B
Max
1.10
0.006
0.05
0.041
0.80
0.007
0.012
0.19
0.30
C
0.004
0.008
0.09
0.20
D
0.114
0.118
0.122
2.90
3.00
3.10
E
0.169
0.173
0.177
4.30
4.40
4.50
e
0.039
0.026 BSC
0.15
1.00
1.05
0.65 BSC
H
0.244
0.252
0.260
6.20
6.40
6.60
L
0.018
0.024
0.030
0.45
0.60
0.75
a
0°
5°
8°
0°
5°
8°
Note: Controlling dimensions are millimeters
TSSOP – 0.034 grams unit weight
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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Ordering Codes
Part Number
Marking
Package Type
Qty per reel
P2811A-08ST
P2811A
8-pin SOIC, tube
0 to 70
P2812A-08ST
P2812A
8-pin SOIC, tube
0 to 70
P2814A-08ST
P2814A
8-pin SOIC, tube
0 to 70
P2811A-08SR
P2811A
8-pin SOIC, tape reel
2,500
0 to 70
P2812A-08SR
P2812A
8-pin SOIC, tape reel
2,500
0 to 70
P2814A-08SR
P2814A
8-pin SOIC, tape reel
2,500
0 to 70
P2811A-08TT
P2811A
8-pin TSSOP, tube
0 to 70
P2812A-08TT
P2812A
8-pin TSSOP, tube
0 to 70
P2814A-08TT
P2814A
8-pin TSSOP, tube
0 to 70
P2811A-08TR
P2811A
8-pin TSSOP, tape reel
2,500
0 to 70
P2812A-08TR
P2812A
8-pin TSSOP, tape reel
2,500
0 to 70
P2814A-08TR
P2814A
8-pin TSSOP, tape reel
2,500
0 to 70
Device Ordering Information
X
2 8 X X
X -
0 8 X X
Package:
ST – SOIC, TUBE
SR - SOIC, T/R
TT – TSSOP, TUBE
TR - TSSOP, T/R
Pin Count
F = Pb FREE
DEVICE NUMBER
Flow:
P = Commercial Temperature Range (0°C to 70°C)
I = Industrial Temperature Range (-25°C to 85°C)
A = Automotive Temperature Range (-40°C to 125°C)
Licensed under US patent Nos 5,488,627 and 5,631,920.
Preliminary datasheet. Specification subject to change without notice.
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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Temperature
P2811/12/14
October 2003
rev
Alliance Semiconductor Corporation
2595, Augustine Drive,
Santa Clara, CA 95054
Tel# 408-855-4900
Fax: 408-855-4999
www.alsc.com
Copyright © Alliance Semiconductor
All Rights Reserved
Preliminary Information
Part Number: P2811/12/14
Document Version:
© Copyright 2003 Alliance Semiconductor Corporation. All rights reserved. Our three-point logo, our name and Intelliwatt are
trademarks or registered trademarks of Alliance. All other brand and product names may be the trademarks of their
respective companies. Alliance reserves the right to make changes to this document and its products at any time without
notice. Alliance assumes no responsibility for any errors that may appear in this document. The data contained herein
represents Alliance's best data and/or estimates at the time of issuance. Alliance reserves the right to change or correct this
data at any time, without notice. If the product described herein is under development, significant changes to these
specifications are possible. The information in this product data sheet is intended to be general descriptive information for
potential customers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or
customer. Alliance does not assume any responsibility or liability arising out of the application or use of any product
described herein, and disclaims any express or implied warranties related to the sale and/or use of Alliance products
including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual
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assumes all risk of such use and agrees to indemnify Alliance against all claims arising from such use.
Low Power EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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