ALSC ASM3I2872AF-08ST Low power peak emi reducing solution Datasheet

ASM3P2872A
October 2005
rev 1.6
Low Power Peak EMI Reducing Solution
Features
The ASM3P2872A uses the most efficient and optimized
modulation profile approved by the FCC and is
Generates an EMI optimized clock signal at the
ƒ
implemented by using a proprietary all digital method.
output
ƒ
Integrated loop filter components
ƒ
Operates with a 3.3V / 2.5V supply
ƒ
Operating current less than 6mA
ƒ
Low power CMOS design
ƒ
Input frequency range: 13MHz to 30MHz for 2.5V
The ASM3P2872A modulates the output of a single PLL
in order to “spread” the bandwidth of a synthesized clock,
and more importantly, decreases the peak amplitudes of
its harmonics. This results in significantly lower system
EMI compared to the typical narrow band signal produced
: 13MHz to 30MHz for 3.3V
Generates a 1X low EMI spread spectrum clock of
ƒ
the input frequency
by oscillators and most frequency generators. Lowering
EMI by increasing a signal’s bandwidth is called ‘spread
spectrum clock generation’.
ƒ
Frequency deviation: -1.25% @ 30MHz
ƒ
Available in 6-pin TSOT-23, 8-pin SOIC and 8-pin
Applications
TSSOP packages.
The ASM3P2872A is targeted towards all portable
Product Description
devices with very low power requirements like MP3
The ASM3P2872A is a versatile spread spectrum
frequency modulator designed specifically for a wide
range of clock frequencies. The ASM3P2872A reduces
electromagnetic interference (EMI) at the clock source,
allowing system wide reduction of EMI of
all clock
players, Notebooks and digital still cameras.
Key Specifications
Description
Specification
Supply voltages
VDD = 3.3V /2.5V
system cost savings by reducing the number of circuit
Cycle-to-Cycle Jitter
200pS (Max)
board layers ferrite beads, shielding that are traditionally
Output Duty Cycle
45/55% (worst case)
required to pass EMI regulations.
Modulation Rate Equation
FIN/640
Frequency Deviation
-1.25% @ 30MHz
dependent signals. The ASM3P2872A allows significant
Block Diagram
VDD
PLL
Modulation
XIN
XOUT
Crystal
Oscillator
Frequency
Divider
Feedback
Divider
Phase
Detector
Loop
Filter
VCO
Output
Divider
REFOUT
VSS
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.
ModOUT
ASM3P2872A
October 2005
rev 1.6
Pin Configuration (6-pin TSOT-23 Package)
REFOUT
1
XOUT
2
ASM3P2872A
XIN/CLKIN 3
6
VSS
5
ModOUT
4
VDD
Pin Description
Pin#
Pin Name
Type
Description
1
REFOUT
O
Buffered output of the input frequency.
2
XOUT
O
Crystal connection. If using an external reference, this pin must be left unconnected.
3
XIN/CLKIN
I
Crystal connection or external reference frequency input. This pin has dual functions. It
can be connected either to an external crystal or an external reference clock.
4
VDD
P
Power supply for the entire chip
5
ModOUT
O
Spread spectrum clock output.
6
VSS
P
Ground connection.
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
2 of 12
ASM3P2872A
October 2005
rev 1.6
Pin Configuration (8-pin SOIC and TSSOP Packages)
XIN/CLKIN
1
XOUT
2
ASM3P2872A
REFOUT 3
NC
8
VDD
7
NC
6
ModOUT
5 VSS
4
Pin Description
Pin#
Pin Name
Type
Description
1
XIN/CLKIN
I
Crystal connection or external reference frequency input. This pin has dual functions. It
can be connected either to an external crystal or an external reference clock.
2
XOUT
O
Crystal connection. If using an external reference, this pin must be left unconnected.
3
REFOUT
O
Buffered output of the input frequency.
4
NC
-
No connect.
5
VSS
P
Ground connection.
6
ModOUT
O
Spread spectrum clock output.
7
NC
-
No connect.
8
VDD
P
Power supply for the entire chip
Modulation Profile
Specifications
Description
Frequency Range
For 2.5V Supply
For 3.3V Supply
Specification
13MHz < CLKIN < 30MHz
13MHz < CLKIN < 30MHz
Modulation Equation
FIN/640
Frequency Deviation
-1.25% @ 30MHz
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
3 of 12
ASM3P2872A
October 2005
rev 1.6
Absolute Maximum Ratings
Symbol
VDD, VIN
TSTG
Parameter
Rating
Unit
Voltage on any pin with respect to Ground
-0.5 to +7.0
V
Storage temperature
-65 to +125
°C
0 to 70
°C
TA
Operating temperature
Ts
Max. Soldering Temperature (10 sec)
260
°C
Junction Temperature
150
°C
2
KV
TJ
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.
DC Electrical Characteristics for 2.5V Supply
(Test condition: All parameters are measured at room temperature (+25°C) unless otherwise stated)
Symbol
Parameter
Min
Typ
Max
Unit
VIL
Input low voltage
VSS - 0.3
-
0.8
V
VIH
Input high voltage
2.0
-
VDD + 0.3
V
IIL
Input low current
-
-
-35
µA
IIH
Input high current
-
-
35
µA
IXOL
XOUT output low current (@0.5V, VDD=2.5V)
-
3
-
mA
IXOH
XOUT output high current (@1.8V, VDD=2.5V)
-
3
-
mA
VOL
Output low voltage (VDD = 2.5 V, IOL = 8 mA)
-
-
0.6
V
VOH
Output high voltage (VDD = 2.5 V, IOH = 8 mA)
1.8
-
-
V
IDD
Static supply current *
-
1.1
-
mA
ICC
Dynamic supply current (2.5V, 30MHz and with no load)
-
4.0
-
mA
2.375
2.5
2.625
V
VDD
tON
ZOUT
Operating voltage
Power-up time (first locked cycle after power-up)
-
-
5
mS
Output impedance
-
50
-
Ω
Min
Typ
Max
Unit
* XIN/CLKIN pin is pulled low
AC Electrical Characteristics for 2.5V Supply
Symbol
Parameter
CLKIN
Input frequency
13
-
30
MHz
ModOUT
Output frequency
13
-
30
MHz
fd
Frequency Deviation
Input Frequency = 13MHz
-
-1.85
-
Input Frequency = 30MHz
-
-0.9
-
tLH*
Output rise time (measured from 0.7V to 1.7V)
0.7
1.5
1.7
nS
tHL*
Output fall time (measured from 1.7V to 0.7V)
0.5
0.9
1.1
nS
tJC
Jitter (cycle to cycle)
-
-
200
pS
tD
Output duty cycle
45
50
55
%
%
* tLH and tHL are measured into a capacitive load of 15pF
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
4 of 12
ASM3P2872A
October 2005
rev 1.6
DC Electrical Characteristics for 3.3V Supply
(Test condition: All parameters are measured at room temperature (+
Symbol
25°C) unless otherwise stated)
Parameter
Min
Typ
Max
Unit
VIL
Input low voltage
VSS - 0.3
-
0.8
V
VIH
Input high voltage
2.0
-
VDD + 0.3
V
IIL
Input low current
-
-
-35
µA
IIH
Input high current
-
-
35
µA
IXOL
XOUT output low current (@0.4V, VDD=3.3V)
-
3
-
mA
IXOH
XOUT output high current (@2.5V, VDD=3.3V)
-
3
-
mA
VOL
Output low voltage (VDD = 3.3 V, IOL = 8 mA)
-
-
0.4
V
VOH
Output high voltage (VDD = 3.3 V, IOH = 8 mA)
2.5
-
-
V
IDD
Static supply current*
-
1.2
-
mA
ICC
VDD
tON
ZOUT
Dynamic supply current (3.3V, 30MHz and with no load)
-
5.5
-
mA
2.7
3.3
3.6
V
Power-up time (first locked cycle after power-up)**
-
-
5
mS
Output impedance
-
45
-
Ω
Operating voltage
* XIN/CLKIN pin is pulled low
AC Electrical Characteristics for 3.3V Supply
Symbol
Parameter
Min
Typ
Max
Unit
CLKIN
Input frequency
13
-
30
MHz
ModOUT
Output frequency
13
-
30
MHz
fd
Frequency Deviation
Input Frequency = 13MHz
-
-1.85
-
Input Frequency = 30MHz
-
-0.9
-
tLH*
Output rise time (measured from 0.8 to 2.0V)
0.5
1.4
1.7
nS
tHL*
Output fall time (measured at 2.0V to 0.8V)
0.4
0.9
1.1
nS
tJC
Jitter (cycle to cycle)
-
-
200
pS
tD
Output duty cycle
45
50
55
%
%
*tLH and tHL are measured into a capacitive load of 15pF
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
5 of 12
ASM3P2872A
October 2005
rev 1.6
Typical Crystal Oscillator Circuit
R1 = 510Ω
Crystal
C1 = 27 pF
C2 = 27 pF
Typical Crystal Specifications
Fundamental AT cut parallel resonant crystal
Nominal frequency
14.31818MHz
Frequency tolerance
± 50 ppm or better at 25°C
Operating temperature range
-25°C to +85°C
Storage temperature
-40°C to +85°C
Load capacitance
18pF
Shunt capacitance
7pF maximum
ESR
25Ω
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
6 of 12
ASM3P2872A
October 2005
rev 1.6
Package Information
6-pin TSOT-23 Package
Dimensions
Symbol
Inches
Min
A
Max
Millimeters
Min
Max
0.04
1.00
A1
0.00
0.004
0.00
0.10
A2
0.033
0.036
0.84
0.90
b
0.012
0.02
0.30
0.50
H
0.005 BSC
0.127 BSC
D
0.114 BSC
2.90 BSC
B
0.06 BSC
1.60 BSC
e
0.0374 BSC
0.950 BSC
C
0.11 BSC
2.80 BSC
L
0.0118
0.02
0.30
0.50
θ
0°
4°
0°
4°
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
7 of 12
ASM3P2872A
October 2005
rev 1.6
8-Pin 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 Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
8 of 12
ASM3P2872A
October 2005
rev 1.6
8-Pin TSSOP Package
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 Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
9 of 12
ASM3P2872A
October 2005
rev 1.6
Ordering Information
Part Number
Marking
ASM3P2872AF-06OR
B4LL
ASM3P2872AF-08TT
Package Type
Temperature
6-Pin TSOT-23, TAPE & REEL, Pb Free
Commercial
3P2872AF
8-Pin TSSOP, TUBE, Pb Free
Commercial
ASM3P2872AF-08TR
3P2872AF
8-Pin TSSOP, TAPE & REEL, Pb Free
Commercial
ASM3P2872AF-08ST
3P2872AF
8-Pin SOIC, TUBE, Pb Free
Commercial
ASM3P2872AF-08SR
3P2872AF
ASM3P2872AG-06OR
B3LL
ASM3P2872AG-08TT
8-Pin SOIC, TAPE & REEL, Pb Free
Commercial
6-Pin TSOT-23, TAPE & REEL, Green
Commercial
3P2872AG
8-Pin TSSOP, TUBE, Green
Commercial
ASM3P2872AG-08TR
3P2872AG
8-Pin TSSOP, TAPE & REEL, Green
Commercial
ASM3P2872AG-08ST
3P2872AG
8-Pin SOIC, TUBE, Green
Commercial
ASM3P2872AG-08SR
3P2872AG
8-Pin SOIC, TAPE & REEL, Green
Commercial
6-Pin TSOT-23, TAPE & REEL
Commercial
ASM3P2872A-06OR
B1LL
ASM3P2872A-08TT
3P2872A
8-Pin TSSOP, TUBE
Commercial
ASM3P2872A-08TR
3P2872A
8-Pin TSSOP, TAPE & REEL
Commercial
ASM3P2872A-08ST
3P2872A
8-Pin SOIC, TUBE
Commercial
ASM3P2872A-08SR
3P2872A
8-Pin SOIC, TAPE & REEL
Commercial
ASM3I2872AF-06OR
B5LL
ASM3I2872AF-08TT
ASM3I2872AF-08TR
6-Pin TSOT-23, TAPE & REEL, Pb Free
Industrial
3I2872AF
8-Pin TSSOP, TUBE, Pb Free
Industrial
3I2872AF
8-Pin TSSOP, TAPE & REEL, Pb Free
Industrial
ASM3I2872AF-08ST
3I2872AF
8-Pin SOIC, TUBE, Pb Free
Industrial
ASM3I2872AF-08SR
3I2872AF
8-Pin SOIC, TAPE & REEL, Pb Free
Industrial
ASM3I2872AG-06OR
B6LL
6-Pin TSOT-23, TAPE & REEL, Green
Industrial
ASM3I2872AG-08TT
3I2872AG
8-Pin TSSOP, TUBE, Green
Industrial
ASM3I2872AG-08TR
3I2872AG
8-Pin TSSOP, TAPE & REEL, Green
Industrial
ASM3I2872AG-08ST
3I2872AG
8-Pin SOIC, TUBE, Green
Industrial
ASM3I2872AG-08SR
3I2872AG
8-Pin SOIC, TAPE & REEL, Green
Industrial
6-Pin TSOT-23, TAPE & REEL
Industrial
Industrial
ASM3I2872A-06OR
B2LL
ASM3I2872A-08TT
3I2872A
8-Pin TSSOP, TUBE
ASM3I2872A-08TR
3I2872A
8-Pin TSSOP, TAPE & REEL
Industrial
ASM3I2872A-08ST
3I2872A
8-Pin SOIC, TUBE
Industrial
ASM3I2872A-08SR
3I2872A
8-Pin SOIC, TAPE & REEL
Industrial
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
10 of 12
ASM3P2872A
October 2005
rev 1.6
Device Ordering Information
A S M 3 P 2 8 7 2 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
PART 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
ALLIANCE SEMICONDUCTOR MIXED SIGNAL PRODUCT
Licensed under U.S Patent Nos 5,488,627 and 5,631,921
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
11 of 12
ASM3P2872A
October 2005
rev 1.6
Alliance Semiconductor Corporation
2575 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: ASM3P2872A
Document Version: v1.6
Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to Alliance Semiconductor, dated 11-11-2003
© 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 property rights, except as express agreed to in Alliance's
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parties. Alliance does not authorize its products 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 Alliance products in such
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claims arising from such use.
Low Power Peak EMI Reducing Solution
Notice: The information in this document is subject to change without notice.
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