PulseCore ASM3I2531AF-08TR Low frequency emi reduction Datasheet

ASM3P2531A
February 2007
rev 1.4
Low Frequency EMI Reduction
Features
dependent signals. It allows significant system cost
•
FCC approved method of EMI attenuation.
savings by reducing the number of circuit board layers
•
Generates a low EMI spread spectrum of the
and
input clock frequency.
regulations.
•
•
traditionally
required
to
pass
EMI
Optimized for input frequency range between
27MHz – 55MHz.
The ASM3P2531A modulates the output of a single PLL
Internal loop filter minimizes external
in order to spread the bandwidth of a synthesized clock,
thereby decreasing the peak amplitudes of its harmonics.
components and board space.
This result in significantly lower system EMI compared to
•
Frequency Deviation: ±1.7%.
•
Low inherent Cycle-to-cycle jitter.
•
3.3 V ± 0.3V Operating Voltage.
•
Ultra low power CMOS design:3.0 mA @ 3.3 V.
•
Supports notebook VGA and other LCD timing
the typical narrow band signal produced by oscillators
and most clock generators. Lowering EMI by increasing
controller applications.
•
shielding
Available in 8-pin SOIC and TSSOP Packages.
a signal’s bandwidth is called spread spectrum clock
generation.
The ASM3P2531A uses the most efficient and optimized
modulation profile approved by the FCC and is
implemented by using a proprietary all-digital method.
Product Description
The ASM3P2531A is a versatile spread spectrum
frequency modulator designed specifically for a wide
range of clock frequencies. It reduces electromagnetic
interference (EMI) at the clock source allowing systemwide reduction of EMI of downstream clock and data
Applications
The ASM3P2531A is targeted toward the notebook VGA
chip and other displays using an LVDS interface, PC
peripheral devices, and embedded systems.
Block Diagram
VDD
STOP
PLL
Modulation
CLKIN
Crystal
Oscillator
Frequency
Divider
Feedback
Divider
Phase
Detector
Loop
Filter
VCO
Output
Divider
ModOUT
VSS
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200, Campbell, CA 95008 • Tel: 408-879-9077 • Fax: 408-879-9018
www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice.
ASM3P2531A
February 2007
rev 1.4
Pin Configuration (8-pin SOIC and TSSOP Packages)
CLKIN
1
VDD
2
8
NC
7
NC
ASM3P2531A
VSS
3
6
NC
ModOUT
4
5
STOP
Spread Range Selection, VDD = 3.3 V
CLKIN frequency
Spreading range
Modulation rate
27MHz – 55MHz
± 1.7%
(CLKIN/1280) KHz
Pin Description
Pin#
Pin Name
Type
Description
1
CLKIN
I
External reference frequency input.
2
VDD
P
Power supply for the entire chip.
3
VSS
P
Ground to entire chip.
4
ModOUT
O
Spread spectrum clock output or reference output.( Refer Standby Mode Selection.)
5
STOP
I
Active LOW signal. When HIGH, enables ModOUT and when LOW, ModOUT would be
LOW.
6
NC
-
No connect.
7
NC
-
No connect.
8
NC
-
No connect.
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
2 of 8
ASM3P2531A
February 2007
rev 1.4
Schematic for a Typical Application
Input clock 27MHz – 55MHz
VDD
FB : Optional ferrite bead
FB
0.1uF
1
CLKIN
NC
8
2
VDD
NC
ASM3P2531A
7
3
VSS
NC
6
4
ModOUT
GND
EMI reduced clock output
27MHz – 55MHz
STOP
5
VDD
0Ω
0Ω
Use either pull-up or pull-down
resistors with 0Ω
Absolute Maximum Ratings
Symbol
Parameter
VDD, VIN
TSTG
TA
Rating
Unit
Voltage on any pin with respect to Ground
-0.5 to +4.6
V
Storage temperature
-65 to +125
°C
Operating temperature
-40 to +85
°C
Ts
Max. Soldering Temperature (10 sec)
260
°C
TJ
Junction Temperature
150
°C
2
KV
TDV
Static Discharge Voltage
(As per JEDEC STD22- A114-B)
Note: These are stress ratings only and are not implied for functional use. Exposure to absolute maximum ratings for prolonged periods of time may affect
device reliability.
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
3 of 8
ASM3P2531A
February 2007
rev 1.4
DC Electrical Characteristics
Symbol
Parameter
Min
Typ
Max
Unit
V
VIL
Input low voltage
VSS - 0.3
0.8
VIH
Input high voltage
2.0
VDD + 0.3
V
IIL
Input low current
-35
µA
IIH
Input high current
35
µA
VOL
Output low voltage
VDD = 3.3V, IOL = 6 mA
0.4
V
VOH
Output high voltage
VDD = 3.3V, IOH = 15 mA
IDD
Static supply current standby mode
ICC
Dynamic supply current
VDD
Operating voltage
tON
Power-up time (first locked cycle after power up)
ZOUT
3.3V and 15pF loading
2.5
V
3.0
10
3.0
Clock output impedance
3.3
mA
14
mA
3.6
V
0.18
mS
50
Ω
AC Electrical Characteristics
Symbol
fIN
Parameter
Input frequency
Min
Typ
27
Unit
55
MHz
fOUT
Output frequency
55
MHz
tLH 1
Output rise time
Measured from 0.8 V to 2.0 V
0.4
0.6
1.2
nS
Output fall time
Measured from 2.0 V to 0.8 V
0.4
0.6
1.2
nS
360
pS
55
%
tHL
1
27
Max
tJC
Jitter (Cycle to cycle)
TD
Output duty cycle
45
50
Note 1: tLH and tHL are measured into a capacitive load of 15pF
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
4 of 8
ASM3P2531A
February 2007
rev 1.4
Package Information
8-lead (150-mil) SOIC Package
H
E
D
A2
A
C
A1
D
θ
e
L
B
Dimensions
Symbol
Inches
Min
Max
Millimeters
Min
Max
A1
0.004
0.010
0.10
0.25
A
0.053
0.069
1.35
1.75
A2
0.049
0.059
1.25
1.50
B
0.012
0.020
0.31
0.51
C
0.007
0.010
0.18
0.25
D
0.193 BSC
4.90 BSC
E
0.154 BSC
3.91 BSC
e
0.050 BSC
1.27 BSC
H
0.236 BSC
6.00 BSC
L
0.016
0.050
0.41
1.27
θ
0°
8°
0°
8°
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
5 of 8
ASM3P2531A
February 2007
rev 1.4
8-lead Thin Shrunk Small Outline Package (4.40-MM Body)
H
E
D
A2
A
C
θ
e
A1
L
B
Dimensions
Symbol
Inches
Min
Millimeters
Max
A
Min
Max
0.043
1.10
A1
0.002
0.006
0.05
0.15
A2
0.033
0.037
0.85
0.95
B
0.008
0.012
0.19
0.30
c
0.004
0.008
0.09
0.20
D
0.114
0.122
2.90
3.10
E
0.169
0.177
4.30
4.50
e
0.026 BSC
0.65 BSC
H
0.252 BSC
6.40 BSC
L
0.020
0.028
0.50
0.70
θ
0°
8°
0°
8°
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
6 of 8
ASM3P2531A
February 2007
rev 1.4
Ordering Information
Ordering Code
Marking
Package Type
Operating Range
ASM3P2531AF-08ST
3P2531AF
8-pin 150mil SOIC –TUBE, Pb free
Commercial
ASM3P2531AF-08SR
3P2531AF
8-pin 150-mil SOIC -TAPE & REEL, Pb free
Commercial
ASM3I2531AF-08ST
3P2531AF
8-pin 150mil SOIC -TUBE, Pb free
Industrial
ASM3I2531AF-08SR
3P2531AF
8-pin 150-mil SOIC -TAPE & REEL, Pb free
Industrial
ASM3P2531AF-08TT
3P2531AF
8-pin 4.4mm TSSOP -TUBE, Pb free
Commercial
ASM3P2531AF-08TR
3P2531AF
8-pin 4.4mm TSSOP -TAPE & REEL, Pb free
Commercial
ASM3I2531AF-08TT
3P2531AF
8-pin 4.4mm TSSOP -TUBE, Pb free
ASM3I2531AF-08TR
3P2531AF
8-pin 4.4mm TSSOP - TAPE & REEL, Pb free
ASM3P2531AG-08ST
3P2531AG
8-pin 150mil SOIC –TUBE, Green
Commercial
ASM3P2531AG-08SR
3P2531AG
8-pin 150-mil SOIC -TAPE & REEL, Green
Commercial
ASM3I2531AG-08ST
3P2531AG
8-pin 150mil SOIC -TUBE, Green
Industrial
ASM3I2531AG-08SR
3P2531AG
8-pin 150-mil SOIC -TAPE & REEL, Green
Industrial
ASM3P2531AG-08TT
3P2531AG
8-pin 4.4mm TSSOP -TUBE, Green
Commercial
ASM3P2531AG-08TR
3P2531AG
8-pin 4.4mm TSSOP -TAPE & REEL, Green
Commercial
ASM3I2531AG-08TT
3P2531AG
8-pin 4.4mm TSSOP -TUBE, Green
Industrial
ASM3I2531AG-08TR
3P2531AG
8-pin 4.4mm TSSOP - TAPE & REEL, Green
Industrial
Industrial
Industrial
Device Ordering Information
A S M 3 P 2 5 3 1 A F - 0 8 T R
R = Tape & Reel, T = Tube or Tray
O = SOT
S = SOIC
T = TSSOP
A = SSOP
V = TVSOP
B = BGA
Q = QFN
U = MSOP
E = TQFP
L = LQFP
U = MSOP
P = PDIP
D = QSOP
X = SC-70
DEVICE PIN COUNT
F = LEAD FREE AND RoHS COMPLIANT PART
G = GREEN PACKAGE, LEAD FREE, and RoHS
DEVICE NUMBER
X= Automotive
I= Industrial
P or n/c = Commercial
(-40C to +125C) (-40C to +85C)
(0C to +70C)
1 = Reserved
2 = Non PLL based
3 = EMI Reduction
4 = DDR support products
5 = STD Zero Delay Buffer
6 = Power Management
7 = Power Management
8 = Power Management
9 = Hi Performance
0 = Reserved
PulseCore Semiconductor Mixed Signal Product
Licensed under US patent #5,488,627, #6,646,463 and #5,631,920.
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
7 of 8
ASM3P2531A
February 2007
rev 1.4
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200
Campbell, CA 95008
Tel: 408-879-9077
Fax: 408-879-9018
www.pulsecoresemi.com
Copyright © PulseCore Semiconductor
All Rights Reserved
Part Number: ASM3P2531A
Document Version: v1.4
Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to PulseCore Semiconductor, dated 11-11-2003
© Copyright 2007 PulseCore Semiconductor Corporation. All rights reserved. Our logo and name are trademarks or
registered trademarks of PulseCore Semiconductor. All other brand and product names may be the trademarks of their
respective companies. PulseCore reserves the right to make changes to this document and its products at any time without
notice. PulseCore assumes no responsibility for any errors that may appear in this document. The data contained herein
represents PulseCore’s best data and/or estimates at the time of issuance. PulseCore 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. PulseCore 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 PulseCore products
including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual
property rights, except as express agreed to in PulseCore’s Terms and Conditions of Sale (which are available from
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The purchase of products from PulseCore does not convey a license under any patent rights, copyrights; mask works rights,
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for use as critical components in life-supporting systems where a malfunction or failure may reasonably be expected to result
in significant injury to the user, and the inclusion of PulseCore products in such life-supporting systems implies that the
manufacturer assumes all risk of such use and agrees to indemnify PulseCore against all claims arising from such use.
Low Frequency EMI Reduction
Notice: The information in this document is subject to change without notice.
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