PulseCore I2784AG-08TT General purpose emi reduction ic Datasheet

P2781/82/84
October 2006
rev 1.6
General Purpose EMI Reduction IC
Features
•
•
•
•
•
•
•
•
•
•
•
•
Provides up to 15dB of EMI suppression
FCC approved method of EMI attenuation
Generates a 1X, 2X, and 4X low EMI spread
spectrum clock of the input frequency
Input frequency range from 3 to 78MHz
External loop filter for spread % adjustment
Spreading ranges from ±0.25% to ±5.0%
Ultra low cycle-to-cycle jitter
Zero-cycle slip
3.3V operating voltage range
Ultra-low power CMOS design
P278xA is available in 8 pin SOIC and TSSOP
Packages
Available for industrial and automotive
temperature ranges.
reduces electromagnetic interference (EMI) at the clock
source, which provides system wide reduction of EMI of
all clock dependent signals. The P278xA allows
significant system cost savings by reducing the number of
circuit board layers and shielding that are traditionally
required to pass EMI regulations.
The P278xA uses the most efficient and optimized
modulation profile approved by the FCC. The P278xA
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 result 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.
Product Description
Applications
The P278xA is a versatile spread spectrum frequency
modulator designed specifically for digital camera and
other digital video and imaging applications. The P278xA
The P278xA is targeted towards MFP, xDSL, fax modem,
set-top box, USB controller, DSC, and embedded systems.
Block Diagram
FS0
FS1
LF
VDD
PLL
Modulation
XIN /CLKIN
XOUT
Crystal
Oscillator
Frequency
Divider
Feedback
Divider
Phase
Detector
Output
Divider
VCO
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.
P2781/82/84
October 2006
rev 1.6
Pin Configuration
XIN / CLKIN
1
XOUT
2
8
VDD
7
FS0
P278xA
FS1
3
6
ModOUT
LF
4
5
VSS
Standard pin Configuration offered in both
8 pin SOIC and TSSOP Packages
Pin Description (P278xA)
Pin#
Pin Name
Type
Description
Connect to crystal or clock input. This pin has dual functions. It can be connected
either to an external crystal or an external reference clock.
Crystal connection. If using an external reference, this pin must be left
unconnected.
Digital logic input used to select input frequency range
(see the Input Frequency Selection Table). This pin has an internal pull-up
resistor.
External Loop Filter for the PLL. By changing the value of the CRC circuit, the
percentage spread can be adjusted accordingly. See the Loop Filter Selection
Table for detail value.
1
XIN/CLKIN
I
2
XOUT
O
3
FS1
I
4
LF
I
5
VSS
I
Ground Connection. Connect to system ground.
6
ModOUT
O
Spread Spectrum Clock Output.
7
FS0
I
Digital logic input used to select input frequency range
(see the Input Frequency Selection Table). This pin has an internal pull-up
resistor.
8
VDD
P
Connect to +3.3 V
Input Frequency Selection Table
FS1
FS0
Input (MHz)
0
0
0
Output Frequency Scaling (MHz)
Modulation Rate (KHz)
P2781A
P2782A
P2784A
3 to 9
3 to 9
6 to 18
12 to 36
Fin / 128
1
10 to 19
10 to 19
20 to 38
40 to 76
Fin / 256
1
0
20 to 38
20 to 38
40 to 76
80 to 152
Fin / 512
1
1
39 to 78
39 to 78
78 to 156
156 to 312
Fin / 1024
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
2 of 11
P2781/82/84
October 2006
rev 1.6
Loop Filter Selection Table VDD 3.3V
Contact PulseCore for loop values that are not listed in the table and for
component selection values for industrial and automotive temperatures.
1
1
BW = ±0.50%
Input
MHz
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21-22
23-24
25-26
27-28
29-30
31-32
33-34
35-36
37-38
39-42
43-46
47-50
51-54
55-58
59-62
63-66
67-70
71-74
75-78
FS1 FS0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
BW = ±0.75%
1
BW = ±1.00%
C1
(pF)
C2
(pF)
R1
(ohm)
C1
(pF)
C2
(pF)
R1
(ohm)
C1
(pF)
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
330,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
220
270
390
510
620
820
1,000
330
390
510
560
620
750
820
910
1,000
1,200
330
390
510
560
620
750
820
910
1,000
1,200
330
390
510
560
620
750
820
910
1,000
1,200
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
330,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
100,000
300
390
560
750
1,000
1,200
1,500
510
560
750
820
1,000
1,100
1,200
1,300
1,500
1,600
560
620
750
820
1,000
1,100
1,200
1,300
1,500
1,600
560
620
750
820
1,000
1,100
1,200
1,300
1,600
1,800
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
270
C2
(pF)
R1
(ohm)
100,000
390
100,000
560
100,000
750
10,000
1,000
5,600
1,200
12,000
2,200
5,600
2,200
100,000
750
100,000 866(1%)
10,000
1,000
12,000
1,200
5,600
1,200
3,900
1,200
12,000
2,200
10,000
2,200
5,600
2,200
3,300
2,200
100,000
750
100,000 866 (1%)
10,000
1,000
12,000
1,200
6,800
1,200
3,900
1,200
12,000
2,200
10,000
2,200
5,600
2,200
3,300
2,200
100,000
750
100,000 866 (1%)
10,000
1,000
12,000
1,200
6,800
1,200
3,900
1,200
12,000
2,200
8,200
2,200
5,600
2,200
3,300
2,200
BW = ±1.25%
C1
(pF)
C2
(pF)
R1
(ohm)
560
560
560
680
330
680
270
560
560
680
470
330
330
680
390
270
270
560
560
680
470
330
330
680
390
270
270
560
560
680
470
330
330
680
390
270
270
100,000
100,000
100,000
6,800
3,300
6,800
2,700
100,000
100,000
6,800
4,700
3,300
3,300
6,800
3,900
2,700
2,700
100,000
100,000
6,800
4,700
3,300
3,300
6,800
3,900
2,700
2,700
100,000
100,000
6,800
4,700
3,300
3,300
6,800
3,900
2,700
2,700
510
680
910
1,200
1,200
2,200
2,200
910
1,100
1,200
1,200
1,200
1,500
2,200
2,200
2,200
2,700
910
1,100
1,200
1,200
1,200
1,500
2,200
2,200
2,200
2,700
910
1,100
1,200
1,200
1,200
1,500
2,200
2,200
2,200
2,700
1 The BW value is representative of typical conditions
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
3 of 11
P2781/82/84
October 2006
rev 1.6
Spread Spectrum Selection
The P278xA performs Zero Cycle Slip when set at low percentage spreading. This allows no occurrence of system timing
error. The optimal setting should minimize system EMI to the fullest without affecting system performance. The spreading is
described as a percentage deviation of the center frequency.
(Note: the center frequency is the frequency of the external reference input on CLKIN, Pin 1.)
The P2781A is designed for PC peripheral, networking, notebook PC, and LCD monitor applications. It is optimized for
operation between 3 to 78MHz range. In the following application schematic example, the P2781A spread percentage
selection is determined by the external LF value specified in the Loop Filter Selection Table. The Input Frequency Selection
Table specifies the input frequency range. The external LF allows the user to fine tune the spread percentage to optimize the
EMI reduction benefits of the spread spectrum.
+3.3V
16 MHz
1 XIN/CLKIN VDD 8
2 XOUT
3 FS1
C2
R1
C1
4 LF
0 Ohm
FS0 7
2.2 K
0.1µF
ModOUT 6
Modulated 16MHz Clock
To target Chip
VSS 5
P278xA
Note: Both logic input pins FS1 and FS0 have to be connected to either VDD or VSS. Do not leave them floating.
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
4 of 11
P2781/82/84
October 2006
rev 1.6
Absolute Maximum Ratings
Symbol
Parameter
Rating
Unit
VDD, VIN
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
TSTG
TA
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.
DC Electrical Characteristics
(Test condition: All parameters are measured at room temperature (+25°C) unless otherwise stated)
Symbol
Parameter
VIL
Input low voltage
VIH
Min
Typ
Max
Unit
VSS – 0.3
-
0.8
V
2.0
-
VDD +0.3
V
-
60
-
µA
-
60
-
µA
IXOL
Input high voltage
Input low current
(internal input pull-up resistor on FS0 and FS1)
Input high current
(internal input pull-up resistor on FS0 and FS1)
XOUT output low current
-
10
-
mA
IXOH
XOUT output high current
-
10
-
mA
VOL
Output low voltage (VDD = 3.3V, IOL = 20mA)
-
-
0.4
V
VOH
Output high voltage (VDD = 3.3V, IOH = 20mA)
2.5
-
-
V
IDD
Static supply current
Typical dynamic supply current
(25pF scope probe loading)
Operating voltage
-
3
-
mA
5.2 at 3MHz
-
21.2 at 82MHz
mA
3.0
3.3
3.6
V
IIL
IIH
ICC
VDD
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
5 of 11
P2781/82/84
October 2006
rev 1.6
AC Electrical Characteristics
Symbol
fIN
fOUT
Parameter
Min
Typ
Max
3
-
78
P2781A
3
-
78
P2782A
6
-
156
P2784A
12
-
312
Input frequency: P278xA
Output frequency:
Unit
MHz
tLH
P278xA
Output rise time (measured at 0.8 V to 2.0 V,
25pF scope probe loading)
-
1
-
nS
tHL
P278xA
Output fall time (measured at 2.0 V to 0.8 V,
25 pF scope probe loading)
-
1
-
nS
tJC
P2781A
Jitter (cycle to cycle, ± 6sigma, 1000 sweeps,
± 0.5% spread, I/O frequency = 16MHz)
-
±250
-
pS
tD
P2781A
Output duty cycle deviation (error from 50%
duty cycle, 25pF scope probe loading)
±1 @ 3MHz
-
±2 @ 82MHz
%
∆F
P278xA
Frequency deviation tolerance from BW%
stated in the Loop Filter Selection Table
-20
0
+20
%
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
6 of 11
P2781/82/84
October 2006
rev 1.6
Package Information
8-Pin SOIC Package
H
E
D
A2
A
C
A1
D
θ
e
L
B
Dimensions
Symbol
Inches
Millimeters
Min
Max
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°
Note: Controlling dimensions are millimeters
SOIC - 0.074 grams unit weight
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
7 of 11
P2781/82/84
October 2006
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°
Note: Controlling dimensions are millimeters
TSSOP - 0.0325 grams unit weight
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
8 of 11
P2781/82/84
October 2006
rev 1.6
Ordering Codes
Ordering #
P278xAF-08ST
Top Marking
P278xAF
Package Type
Temperature
8 PIN SOIC, TUBE, Pb Free
Commercial
P278xAF-08SR
P278xAF
8 PIN SOIC, TAPE AND REEL,Pb Free
Commercial
P278xAF-08TT
P278xAF
8 PIN TSSOP, TUBE, Pb Free
Commercial
P278xAF-08TR
P278xAF
8 PIN TSSOP, TAPE AND REEL, Pb Free
Commercial
P278xAG-08ST
P278xAG
8 PIN SOIC, TUBE, Green
Commercial
P278xAG-08SR
P278xAG
8 PIN SOIC, TAPE AND REEL, Green
Commercial
P278xAG-08TT
P278xAG
8 PIN TSSOP, TUBE, Green
Commercial
P278xAG-08TR
P278xAG
8 PIN TSSOP, TAPE AND REEL, Green
Commercial
I278xAF-08ST
I278xAF
8 PIN SOIC, TUBE, Pb Free
Industrial
I278xAF-08SR
I278xAF
8 PIN SOIC, TAPE AND REEL,Pb Free
Industrial
I278xAF-08TT
I278xAF
8 PIN TSSOP, TUBE, Pb Free
Industrial
I278xAF-08TR
I278xAF
8 PIN TSSOP, TAPE AND REEL, Pb Free
Industrial
I278xAG-08ST
I278xAG
8 PIN SOIC, TUBE, Green
Industrial
I278xAG-08SR
I278xAG
8 PIN SOIC, TAPE AND REEL, Green
Industrial
I278xAG-08TT
I278xAG
8 PIN TSSOP, TUBE, Green
Industrial
I278xAG-08TR
I278xAG
8 PIN TSSOP, TAPE AND REEL, Green
X278xAF-08ST
X278xAF
8 PIN SOIC, TUBE, Pb Free
Automotive
X278xAF-08SR
X278xAF
8 PIN SOIC, TAPE AND REEL, Pb Free
Automotive
X278xAF-08TT
X278xAF
8 PIN TSSOP, TUBE, Pb Free
Automotive
X278xAF-08TR
X278xAF
8 PIN TSSOP, TAPE AND REEL, Pb Free
Automotive
Industrial
X278xAG-08ST
X278xAG
8 PIN SOIC, TUBE, Green
Automotive
X278xAG-08SR
X278xAG
8 PIN SOIC, TAPE AND REEL, Green
Automotive
X278xAG-08TT
X278xAG
8 PIN TSSOP, TUBE, Green
Automotive
X278xAG-08TR
X278xAG
8 PIN TSSOP, TAPE AND REEL, Green
Automotive
Note: x=1/2/4
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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P2781/82/84
October 2006
rev 1.6
Device Ordering Information
P 2 7 8 x A
F
0 8 X X
Package:
ST – SOIC, TUBE
SR - SOIC, T/R
TT – TSSOP, TUBE
TR - TSSOP, T/R
Pin Count
F = LEAD FREE or RoHS COMPLIANT PART
G = GREEN PACKAGE, LEAD FREE, and RoHS
DEVICE NUMBER
Flow:
P = Commercial Temperature Range (0°C to 70°C)
I = Industrial Temperature Range (-40°C to 85°C)
X = Automotive Temperature Range (-40°C to +125°C)
Note: x=1/2/4
Licensed under US patent #5,488,627, #6,646,463 and #5,631,920
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
10 of 11
P2781/82/84
October 2006
rev 1.6
PulseCore Semiconductor Corporation
1715 S. Bascom Avenue Suite 200,
Campbell, CA 95008
Tel # - 408-879-9077
Fax # - 408-879-9018
www.pulsecoresemi.com
Copyright © PulseCore Semiconductor
All Rights Reserved
Part Number: P2781/82/84
Document Version: 1.6
Note: This product utilizes US Patent # 6,646,463 Impedance Emulator Patent issued to PulseCore Semiconductor, dated 11-11-2003
© Copyright 2006 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
PulseCore). All sales of PulseCore products are made exclusively according to PulseCore’s Terms and Conditions of Sale.
The purchase of products from PulseCore does not convey a license under any patent rights, copyrights; mask works rights,
trademarks, or any other intellectual property rights of PulseCore or third parties. PulseCore 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 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.
General Purpose EMI Reduction IC
Notice: The information in this document is subject to change without notice.
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