© Semiconductor Components Industries, LLC, 2011
August, 2011 − Rev. 3
1Publication Order Number:
ASM3P2759A/D
ASM3P2759A
Low Power Peak EMI
Reducing Solution
Description
The ASM3P2759A is a versatile spread spectrum frequency
modulator designed specifically for a wide range of clock frequencies.
The ASM3P2759A reduces electromagnetic interference (EMI) at the
clock source, allowing system wide reduction of EMI of all clock
dependent signals. The ASM3P2759A allows significant system cost
savings by reducing the number of circuit board layers, ferrite beads
and shielding that are traditionally required to pass EMI regulations.
The ASM3P2759A uses the most efficient and optimized
modulation profile approved by the FCC and is implemented by using
a proprietary all digital method.
The ASM3P2759A 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 by oscillators and most frequency generators.
Lowering EMI by increasing a signal’s bandwidth is called ‘spread
spectrum clock generation.’
Applications
The ASM3P2759A is targeted towards all portable devices with
very low power requirements like MP3 players and digital still
cameras.
Features
•Generates an EMI Optimized Clock Signal at the Output
•Integrated Loop Filter Components
•Operates with a 3.3 V / 2.5 V Supply
•Operating Current less than 4 mA
•Low Power CMOS Design
•Input Frequency Range:
3 MHz to 5 MHz for 2.5 V
3 MHz to 6 MHz for 3.3 V
•Generates a 1X Low EMI Spread Spectrum Clock of the Input
Frequency
•Frequency Deviation: ±1% @ 3 MHz
•Available in 6−pin TSOT−23, 8−pin SOIC and 8−pin TSSOP
Packages
•These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS
Compliant
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TSOT−6
O SUFFIX
CASE 419AF
PIN CONFIGURATIONS
6−Pin TSOT−23 Package
(Top View)
See detailed ordering and shipping information in the package
dimensions section on page 9 of this data sheet.
ORDERING INFORMATION
VSS
ModOUT
VDD
XOUT
PD
1
XIN / CLKIN
VDD = 3.3 V / 2.5 VSupply Voltages
200 pS (Max)
Cycle−to−Cycle Jitter
45/55%Output Duty Cycle
FIN/128Modulation Rate Equation
±1% @ 3 MHzFrequency Deviation
Description Specification
KEY SPECIFICATIONS
SOIC−8
S SUFFIX
CASE 751BD
TSSOP−8
T SUFFIX
CASE 948AL
8−Pin SOIC and TSSOP Packages
(Top View)
1
VSS
ModOUT
VDD
XOUT
PD
XIN / CLKIN
NC
NC
ASM3P2759A
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Figure 1. Block Diagram
XOUT
XIN
VSS
Crystal
Oscillator
VDD
Frequency
Divider
Feedback
Divider
PD
Modulation
Phase
Detector
Loop
Filter
PLL
VCO
ModOUT
Output
Divider
Table 1. PIN DESCRIPTION (6−Pin TSOT−23 Package)
Pin# Pin Name Type Description
1 PD I Power−down control pin. Pull low to enable power−down mode. Connect to VDD if not used.
2 XOUT O Crystal connection. If using an external reference, this pin must be left unconnected.
3XIN / CLKIN ICrystal 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.
Table 2. PIN DESCRIPTION (8−Pin SOIC and TSSOP Packages)
Pin# Pin Name Type Description
1XIN / CLKIN ICrystal 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 PD I Power−down control pin. Pull low to enable power−down mode. Connect to VDD if not used.
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.
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Figure 2. Modulation Profile
Table 3. SPECIFICATION
Description Specification
Frequency Range For 2.5 V Supply 3 MHz < CLKIN < 5 MHz
For 3.3 V Supply 3 MHz < CLKIN < 6 MHz
Modulation Equation FIN/128
Frequency Deviation ±1% @ 3 MHz
Table 4. ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Rating Unit
VDD, VIN Voltage on any pin with respect to Ground −0.5 to +4.6 V
TSTG Storage temperature −65 to +125 °C
TAOperating temperature −40 to +85 °C
TsMax. Soldering Temperature (10 sec) 260 °C
TJJunction Temperature 150 °C
TDV Static Discharge Voltage (As per JEDEC STD22− A114−B) 2 KV
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
Table 5. DC ELECTRICAL CHARACTERISTICS FOR 2.5 V 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 mA
IIH Input high current − − 35 mA
IXOL XOUT output low current (@ 0.5 V, VDD = 2.5 V) −3−mA
IXOH XOUT output high current (@ 1.8 V, VDD = 2.5 V) −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 (Note 1) − − 10 mA
ICC Dynamic supply current (2.5 V, 3 MHz and with no load) −2.0 −mA
VDD Operating Voltage 2.375 2.5 2.625 V
tON Power−up time (first locked cycle after power−up) (Note 2) − − 5 mS
ZOUT Output impedance −50 −W
1. XIN / CLKIN and PD pin are pulled low.
2. VDD and XIN / CLKIN input are stable, PD pin is made high from low.
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Table 6. AC ELECTRICAL CHARACTERISTICS FOR 2.5 V SUPPLY
Symbol Parameter Min Typ Max Unit
CLKIN Input frequency 3−5 MHz
ModOUT Output frequency 3−5 MHz
fdFrequency Deviation Input Frequency = 3 MHz −±1−%
Input Frequency = 5 MHz −±0.6 −
tLH (Note 3) Output rise time (measured from 0.7 V to 1.7 V) 0.5 1.0 1.2 nS
tHL (Note 3) Output fall time (measured from 1.7 V to 0.7 V) 0.4 0.9 1.1 nS
tJC Jitter (cycle−to−cycle) − − 200 pS
tDOutput duty cycle 45 50 55 %
3. tLH and tHL are measured into a capacitive load of 15 pF.
Table 7. DC ELECTRICAL CHARACTERISTICS FOR 3.3 V 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 mA
IIH Input high current − − 35 mA
IXOL XOUT output low current (@ 0.4 V, VDD = 3.3 V) −3−mA
IXOH XOUT output high current (@ 2.5 V, VDD = 3.3 V) −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 (Note 4) −10 mA
ICC Dynamic supply current (3.3 V, 3 MHz and with no load) −2.5 −mA
VDD Operating Voltage 2.7 3.3 3.6 V
tON Power−up time (first locked cycle after power−up) (Note 5) − − 5 mS
ZOUT Output impedance −45 −W
4. XIN / CLKIN and PD pin are pulled low.
5. VDD and XIN / CLKIN input are stable; PD pin is made high from low.
Table 8. AC ELECTRICAL CHARACTERISTICS FOR 3.3 V SUPPLY
Symbol Parameter Min Typ Max Unit
CLKIN Input frequency 3−6 MHz
ModOUT Output frequency 3−6 MHz
fdFrequency Deviation Input Frequency = 3 MHz −±1−%
Input Frequency = 6 MHz −±0.55 −
tLH (Note 6) Output rise time (measured from 0.8 to 2.0 V) 0.4 1.0 1.2 nS
tHL (Note 6) Output fall time (measured at 2.0 V to 0.8 V) 0.4 0.9 1.0 nS
tJC Jitter (cycle−to−cycle) − − 200 pS
tDOutput duty cycle 45 50 55 %
6. tLH and tHL are measured into a capacitive load of 15 pF.
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Figure 3. Typical Crystal Oscillator Circuit
R1 = 510 W
Crystal
C2 = 27 pF
C1 = 27 pF
Table 9. TYPICAL CRYSTAL SPECIFICATIONS
Fundamental AT Cut Parallel Resonant Crystal
Nominal frequency 4.800 MHz
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 18 pF
Shunt capacitance 7 pF maximum
ESR 25 W
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PACKAGE DIMENSIONS
TSOT−23, 6 LEAD
CASE 419AF−01
ISSUE O
E1 E
A2
A1
e
b
D
c
A
TOP VIEW
SIDE VIEW END VIEW
L1
LL2
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC MO-193.
SYMBOL
θ
MIN NOM MAX
q
A
A1
A2
b
c
D
E
E1
e
L
0º 8º
L1
L2
0.01
0.80
0.30
0.12
0.30
0.05
0.87
0.15
2.90 BSC
2.80 BSC
1.60 BSC
0.95 TYP
0.40
0.60 REF
0.25 BSC
1.00
0.10
0.90
0.45
0.20
0.50
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PACKAGE DIMENSIONS
SOIC 8, 150 mils
CASE 751BD−01
ISSUE O
E1 E
A
A1
h
θ
L
c
eb
D
PIN # 1
IDENTIFICATION
TOP VIEW
SIDE VIEW END VIEW
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC MS-012.
SYMBOL MIN NOM MAX
θ
A
A1
b
c
D
E
E1
e
h
0º 8º
0.10
0.33
0.19
0.25
4.80
5.80
3.80
1.27 BSC
1.75
0.25
0.51
0.25
0.50
5.00
6.20
4.00
L0.40 1.27
1.35
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PACKAGE DIMENSIONS
TSSOP8, 4.4x3
CASE 948AL−01
ISSUE O
E1 E
A2
A1
e
b
D
c
A
TOP VIEW
SIDE VIEW END VIEW
q1
L1 L
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC MO-153.
SYMBOL
θ
MIN NOM MAX
A
A1
A2
b
c
D
E
E1
e
L1
0º 8º
L
0.05
0.80
0.19
0.09
0.50
2.90
6.30
4.30
0.65 BSC
1.00 REF
1.20
0.15
1.05
0.30
0.20
0.75
3.10
6.50
4.50
0.90
0.60
3.00
6.40
4.40
ASM3P2759A
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Table 10. ORDERING INFORMATION
Part Number Marking Package Type Temperature
ASM3P2759AF−06OR O4LL 6−Pin TSOT−23, TAPE & REEL, Pb Free Commercial
ASM3P2759AF−08TT 3P2759AF 8−Pin TSSOP, TUBE, Pb Free Commercial
ASM3P2759AF−08TR 3P2759AF 8−Pin TSSOP, TAPE & REEL, Pb Free Commercial
ASM3P2759AF−08ST 3P2759AF 8−Pin SOIC, TUBE, Pb Free Commercial
ASM3P2759AF−08SR 3P2759AF 8−Pin SOIC, TAPE & REEL, Pb Free Commercial
ASM3P2759AG−06OR O3LL 6−Pin TSOT−23, TAPE & REEL, Green Commercial
ASM3P2759AG−08TT 3P2759AG 8−Pin TSSOP, TUBE, Green Commercial
ASM3P2759AG−08TR 3P2759AG 8−Pin TSSOP, TAPE & REEL, Green Commercial
ASM3P2759AG−08ST 3P2759AG 8−Pin SOIC, TUBE, Green Commercial
ASM3P2759AG−08SR 3P2759AG 8−Pin SOIC, TAPE & REEL, Green Commercial
ASM3I2759AF−06OR O5LL 6−Pin TSOT−23, TAPE & REEL, Pb Free Industrial
ASM3I2759AF−08TT 3I2759AF 8−Pin TSSOP, TUBE, Pb Free Industrial
ASM3I2759AF−08TR 3I2759AF 8−Pin TSSOP, TAPE & REEL, Pb Free Industrial
ASM3I2759AF−08ST 3I2759AF 8−Pin SOIC, TUBE, Pb Free Industrial
ASM3I2759AF−08SR 3I2759AF 8−Pin SOIC, TAPE & REEL, Pb Free Industrial
ASM3I2759AG−06OR O6LL 6−Pin TSOT−23, TAPE & REEL, Green Industrial
ASM3I2759AG−08TT 3I2759AG 8−Pin TSSOP, TUBE, Green Industrial
ASM3I2759AG−08TR 3I2759AG 8−Pin TSSOP, TAPE & REEL, Green Industrial
ASM3I2759AG−08ST 3I2759AG 8−Pin SOIC, TUBE, Green Industrial
ASM3I2759AG−08SR 3I2759AG 8−Pin SOIC, TAPE & REEL, Green Industrial
ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice
to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should
Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates,
and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death
associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal
Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
ASM3P2759A/D
PUBLICATION ORDERING INFORMATION
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USA/Canada
Europe, Middle East and Africa Technical Support:
Phone: 421 33 790 2910
Japan Customer Focus Center
Phone: 81−3−5773−3850
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