November 2006
rev 1.1
Peak Reducing EMI Solution
Features
•
•
•
•
P2180 / 81 / 82 / 83 / 84
FCC approved method of EMI attenuation.
Provides up to 15dB EMI reduction.
Generates a 1X low EMI spread spectrum clock
from the input frequency.
Optimized for frequency range:
•
•
•
•
•
•
•
•
•
Eight spread % selections:
•
± 0.625% to -3.5%.
3.3V operating voltage.
CMOS/TTL compatible inputs and outputs.
Low-power CMOS design.
Supports notebook VGA and other LCD timing
controller applications.
Drop-in replacement to Cypress W180/1.
Products are available for industrial temperature
range.
Available in 8-pin SOIC and TSSOP packages.
P2180 / 84: 20MHz to 40MHz
P2181: 60MHz to 160MHz
P2182 / 83: 10MHz to 20MHz
loop
filter
minimizes
external
•
•
•
Internal
•
•
components and board space.
Selectable spread options: Down Spread and
Center Spread.
Low inherent cycle-to-cycle jitter.
Product Description
The P2180/81X is a versatile spread spectrum
frequency modulator designed specifically for a
wide range of clock frequencies from 20MHz to
40MHz and 60MHz to 160MHz
(Refer Input
Frequency and Modulation Rate Table.)
The
P2180/81X can generate an EMI reduced clock
form an OSC or a system generated clock. The
P2180/81A
to
P2180/81D
offer
various
combinations of spread options and percentage
deviations.
(Refer Spread Deviation Selections
Table.)
These combinations include Down and
Center Spread and percentage deviation range
from ± 0.625% to –3.50%.
The
P2180/81X
reduces
electromagnetic
interference (EMI) at the clock source, allowing
system wide reduction of EMI of down stream clock
and data dependent signals. The P2180/81X allows
significant system cost savings by reducing the
number of circuit board layers and shielding that
are traditionally required to pass EMI regulations.
The P2180/81X modulates the output of a single
PLL in order to “spread” the bandwidth of a
synthesized clock, thereby decreasing 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 clock generators. Lowering EMI by
increasing a signal’s bandwidth is called spread
spectrum clock generation.
The P2180/81X uses the most efficient and
optimized modulation profile approved by the FCC
and is implemented by using a proprietary all-digital
method.
Applications
The P2180/81X is targeted towards EMI
management for memory and LVDS interfaces in
mobile graphic chipsets and high-speed digital
applications such as PC peripheral devices,
consumer electronics, and embedded controller
systems.
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.
November 2006
rev 1.1
Input Frequency and Modulation Rate
Part Number
P2180/P2184
P2181
P2182/P2183
Input Frequency Range (MHz)
20 to 40
60 to 160
10 to 20
P2180 / 81 / 82 / 83 / 84
Output Frequency Range (MHz)
20 to 40
60 to 160
10 to 20
Modulation Rate
Input frequency / 768
Input frequency / 2048
TBD
Spread Deviation Selections
Part Number
P2180/1/2/3/4
A
P2180/1/2/3/4
B
P2180/1/2/3/4
C
P2180/1/2/3/4
D
SRS
0
1
0
1
0
1
0
1
Spread Deviation
-1.25% (Down)
-1.75% (Down)
± 1.25% (Center)
± 1.75% (Center)
-2.50% (Down)
-3.50 (Down)
± 0.625%(Center)
± 0.875% (Center)
Absolute Maximum Ratings
Symbol
VDD, V
IN
T
STG
T
A
T
s
T
J
T
DV
Storage temperature
Operating temperature
Max. Soldering Temperature (10 sec)
Junction Temperature
Static Discharge Voltage (As per JEDEC STD22- A114-B)
Parameter
Voltage on any pin with respect to Ground
Rating
-0.5 to +4.6
-65 to +125
0 to +70
260
150
2
Unit
V
°C
°C
°C
°C
KV
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 EMI Clock for Mobile VGA
Notice: The information in this document is subject to change without notice.
3 of 9
November 2006
rev 1.1
DC Electrical Characteristics
Unless otherwise noted, V
DD
= 3.3V and T
A
=25°C
P2180 / 81 / 82 / 83 / 84
Symbol
V
IL
V
IH
I
IL
I
IH
I
XOL
I
XOH
V
OL
V
OH
I
CC
I
DD
V
DD
t
ON
Z
OUT
Input low voltage
Input high voltage
Parameter
Min
GND – 0.3
-
-60.0
-
2.00
-
-
2.8
8.6 f
IN
- min
-
-
-
-
Typ
-
-
-
-
-
-
-
-
-
4.5
3.3
-
-
Max
0.8
V
DD
+ 0.3
-20.0
1.00
12.00
12.00
0.4
-
27.0 f
IN
- max
-
-
-
-
Unit
V
V
µA
µA
mA
mA
V
V
mA
mA
V
mS
Ω
Input low current (input SRS)
Input high current
X
OUT
output low current (@ 0.4V, V
DD
= 3.3V)
X
OUT
output high current (@2.5V, V
DD
= 3.3V)
Output low voltage (V
DD
= 3.3V, I
OL
= 20mA)
Output high voltage (V
DD
= 3.3V, I
OH
= 20mA)
Dynamic supply current normal mode (3.3V and
10pF loading)
Static supply current standby mode
Operating voltage
Power up time (first locked clock cycle after power
up)
Clock output impedance
AC Electrical Characteristics
Symbol
f
IN
f
OUT
t
LH
*
t
HL
*
t
JC
t
D
Input frequency
Output frequency
Output rise time (measured at 0.8V to 2.0V)
Output fall time (measured at 2.0V to 0.8V)
Jitter (cycle to cycle)
Output duty cycle
Parameter
Min
10
10
-
-
-200
45
Typ
-
-
0.69
0.66
-
50
Max
160
160
-
-
200
55
Unit
MHz
MHz
ns
ns
ps
%
* t
LH
and t
HL
are measured into a capacitive load of 15pF
Low EMI Clock for Mobile VGA
Notice: The information in this document is subject to change without notice.
4 of 9
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