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Электронный компонент: P1708C-08ST

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June 2004
P1708C

rev 1.1
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.
Low Power Notebook LCD Panel EMI Reduction IC

Features
FCC approved method of EMI attenuation.
Generates a low EMI spread spectrum clock of the
input frequency.
Optimized for frequency range from 50 to 110MHz.
Internal loop filter minimizes external components
and board space.
Four selectable spread ranges.
Low inherent cycle-to-cycle jitter.
3.3V operating voltage range.
TTL or CMOS compatible inputs and outputs.
Ultra-low power CMOS design.
8.46 mA @3.3V, 54MHz
9.79 mA @3.3V, 65MHz
12.06 mA @3.3V, 81MHz
16.51 mA @3.3V, 108MHz
Supports notebook VGA and other LCD timing
controller applications.
Pinout compatible to ICS MK1708 and Cypress
CY25560.
SSON/SBM pin for Spread Spectrum On/Off and
Standby Mode controls.
Available in 8-pin SOIC and TSSOP.

Product Description
The P1708C is a versatile spread spectrum frequency
modulator designed specifically for input clock frequencies.
The P1708C reduces electromagnetic interference (EMI) at
the clock source, allowing system wide reduction of EMI of
down stream clock and data dependent signals. The
P1708C 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.

The P1708C 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'.
The P1708C uses the most efficient and optimized
modulation profile approved by the FCC and is
implemented in a proprietary all digital method.

Applications
The P1708C is targeted towards notebook LCD displays,
and other displays using an LVDS interface, PC peripheral
devices, and embedded systems.



Block Diagram
VSS
CLKIN
Frequency
Divider
Feedback
Divider
Modulation
Phase
Detector
Loop
Filter
VCO
Output
Divider
ModOUT
PLL
VDD
SSON
SR0 SR1
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June 2004
P1708C

rev 1.1
Low Power Notebook LCD Panel EMI Reduction IC
2 of 10
Notice: The information in this document is subject to change without notice.
SSON/SBM
1
2
3
4
5
6
7
8
P1708C
CLKIN
VDD
VSS
ModOUT
SR1
SR0
NC


Pin Configuration














Pin Description

Pin#
Pin Name
Type
Description
1 CLKIN I
Connect to externally generated clock signal. To put the part into standby
mode, disable the input clock signal to this pin and pull SSON/SBM (pin 5)
low. Refer Standby Mode Selection Table.
2
VDD
P
Connect to +3.3V.
3
VSS
P
Ground Connection. Connect to system ground.
4
ModOUT
O
Spread spectrum clock output.
5 SSON/SBM I
Spread Spectrum On/Off and standby mode control. Refer Standby Mode
Selection Table.
This pin has an internal pull-up resistor.
6 SR1 I
Digital logic input used to select Spreading Range. Refer Spread Spectrum
Selection Table.
This pin has an internal pull-up resistor.
7 SR0 I
Digital logic input used to select Spreading Range. Refer Spread Spectrum
Selection Table.
This pin has an internal pull-up resistor.
8 NC -
No
connect.



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Low Power Notebook LCD Panel EMI Reduction IC
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Notice: The information in this document is subject to change without notice.

Standby Mode Selection
CLKIN
SSON/SBM
Spread
Spectrum
ModOUT
PLL
Mode
Disabled 0 N/A Disabled
Disabled
Standby
Disabled
1
N/A
Disabled
Free Running
Free Running
Enabled 0
Off
Reference
Disabled
Buffer
out
Enabled 1
On Normal Normal Normal



Spread Range Selection
SR1
SR0
Spreading Range
Modulation Rate
0 0
1.00%
(F
IN
/40) * 62.49 KHz
0 1
2.00%
(F
IN
/40) * 62.49 KHz
1 0
0.25%
(F
IN
/40) * 62.49 KHz
1 1
0.75%
(F
IN
/40) * 62.49 KHz
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Notice: The information in this document is subject to change without notice.



Schematic for Notebook VGA Application
































Note: To set the P1708C to standby mode, disable the input clock (pin 1 CLKIN) and pull SSON (pin 5) low. Refer Standby Mode Selection
Table.
Pin 8 can be tied either high or low,
or it can be left unconnected.
Tie SR0 and SR1 high/low
according to spread range desired.
External resistors are not needed to
pull these pins high.
Pin 5 SSON should be left unconnected to turn on
spread spectrum. Pull this pin low to turn spread
spectrum OFF and enable stand-by mode.
50MHz to 110MHz pixel clock input
from VGA chip
FB
VDD
0.1F
1
2
4
3
8
7
5
6
CLKIN
VDD
VSS
ModOUT
SSON
SR1
SR0
NC
P1708C
50MHz 110MHz Pixel Clock
Input from VGA Chip
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Low Power Notebook LCD Panel EMI Reduction IC
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Notice: The information in this document is subject to change without notice.

Absolute Maximum Ratings
Symbol
Parameter
Rating
Unit
V
DD
, V
IN
Voltage on any pin with respect to GND
-0.5 to + 7.0
V
T
STG
Storage
temperature
-65 to +125
C
T
A
Operating
temperature
0 to 70
C
Note: These are stress ratings only and functional operation is not implied. Exposure to absolute maximum
ratings for extended periods may affect device reliability.




DC Electrical Characteristics
Symbol
Parameter
Min
Typ
Max
Unit
V
IL
Input low voltage
GND 0.3
-
0.8
V
V
IH
Input high voltage
2.0
-
V
DD
+ 0.3
V
I
IL
Input low current (pull-up resistors on inputs SR0, SR1
and SSON/SBM)
- -
-35
A
I
IH
Input high current
-
-
35
A
I
XOL
X
OUT
output low current @ 0.4V, V
DD
= 3.3V
-
3
-
mA
I
XOH
X
OUT
output high current @ 2.5V, V
DD
= 3.3V
-
3
-
mA
V
OL
Output low voltage V
DD
= 3.3V, I
OL
= 20mA
-
-
0.4
V
V
OH
Output high voltage V
DD
= 3.3V, I
OH
= 20mA
2.5
-
-
V
I
CC
Dynamic supply current normal mode
3.3V and 10pF loading
7.90 9.79
17.53
f
IN
-max
mA
I
DD
Static supply current standby mode
-
0.6
-
mA
V
DD
Operating
voltage
2.7 3.3 3.7 V
t
ON
Power up time (first locked clock cycle after power up)
-
0.18
-
mS
Z
OUT
Clock output impedance
-
50
-

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Low Power Notebook LCD Panel EMI Reduction IC
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Notice: The information in this document is subject to change without notice.


AC Electrical Characteristics
Symbol
Parameter
Min
Typ
Max
Unit
f
IN
Input frequency
50
-
110
MHz
f
OUT
Output
frequency
50
-
110
MHz
t
LH
*
Output rise time
Measured at 0.8V to 2.0V
0.7 0.9
1.1
ns
t
HL
*
Output fall time
Measured at 0.8V to 2.0V
0.6 0.8
1.0
ns
t
JC
Jitter (cycle to cycle)
-
-
360
ps
t
D
Output duty cycle
45
50
55
%
*t
LH
and t
HL
are measured into a capacitive load of 15pF

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June 2004
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rev 1.1
Low Power Notebook LCD Panel EMI Reduction IC
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Notice: The information in this document is subject to change without notice.
D
E
H
D
A1
A2
A
L
C
B
e


Package Information
Mechanical Package Outline 8-Pin SOIC




















Symbol Dimensions in inches Dimensions in millimeters
Min
Max
Min
Max
A 0.057 0.071 1.45
1.80
A1 0.004 0.010 0.10
0.25
A2 0.053 0.069 1.35
1.75
B 0.012 0.020 0.31
0.51
C 0.004 0.01 0.10
0.25
D 0.186 0.202 4.72
5.12
E 0.148 0.164 3.75
4.15
e
0.050 BSC
1.27 BSC
H 0.224 0.248 5.70
6.30
L 0.012 0.028 0.30
0.70
0 8 0
8
Note: Controlling dimensions are millimeters
SOIC 0.074 grams unit weight


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June 2004
P1708C

rev 1.1
Low Power Notebook LCD Panel EMI Reduction IC
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Notice: The information in this document is subject to change without notice.
E
H
A
A1
A2
D
B
C
L
e



Mechanical Package Outline 8-Pin TSSOP









Dimensions in inches
Dimensions in millimeters
Symbol
Min
Max
Min
Max
A
0.047
1.10
A1
0.002
0.006
0.05
0.15
A2
0.031
0.041
0.80
1.05
B
0.007
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
0.244
0.260
6.20
6.60
L
0.018
0.030
0.45
0.75
0 8 0 8
Note: Controlling dimensions are millimeters
TSSOP 0.034 grams unit weight
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June 2004
P1708C

rev 1.1
Low Power Notebook LCD Panel EMI Reduction IC
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Notice: The information in this document is subject to change without notice.

Ordering Codes
Part Number
Marking
Package Type
Qty per reel
Temperature
(C)
P1708C-08ST
P1708C
8-pin SOIC, tube
0 to 70
P1708C-08SR
P1708C
8-pin SOIC, tape & reel
2500
0 to 70
P1708C-08TT
P1708C
8-pin TSSOP, tube
0 to 70
P1708C-08TR
P1708C
8-pin TSSOP, tape and reel
2500
0 to 70
P1708CF-08ST
P1708CF
8-pin SOIC, tube
0 to 70
P1708CF-08SR
P1708CF
8-pin SOIC, tape & reel
2500
0 to 70
P1708CF-08TT
P1708CF
8-pin TSSOP, tube
0 to 70
P1708CF-08TR
P1708CF
8-pin TSSOP, tape and reel
2500
0 to 70

Device Ordering Information

P 1 7 0 8 C F - 0 8 X X


















Licensed under US patent #5,488,627, #6,646,463 and #5,631,920.
OR - SOT23/T/R
SR - SOIC, T/R
TT TSSOP, TUBE
QR QFN, T/R
TR - TSSOP, T/R
QT - QFN, TUBE
VT TVSOP, TUBE
BT - BGA, TUBE
VR TVSOP, T/R
BR BGA, T/R
ST SOIC, TUBE
DEVICE NUMBER
Flow:
P = Commercial Temperature Range (0C to 70C)
I = Industrial Temperature Range (-25C to 85C)
Pin Count
Pb FREE
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June 2004
P1708C

rev 1.1
Low Power Notebook LCD Panel EMI Reduction IC
10 of 10
Notice: The information in this document is subject to change without notice.


































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