2 Line Ferrite Common
Mode Power Chokes
COMMON MODE
Steward’s
common mode power/data filter products provide the most economi
cal EMI filtering available for common mode noise. They provide EMI suppres
sion for conductors such as power traces (tracks), and for high speed input/
output circuitry (including network and storage subsystems). They exhibit high
frequency impedance essentially independent of DC bias current.
Features:
Protected by one or more of the following US Patents: 5,455,552 and 5,568,111
·High
current capability (10 amps continuous operation)
·Up
to 170 ohms impedance @100MHz or 300 ohms @1GHz
·Parts
available in both thru-hole (B) and surface mount (R) versions
·Parts
available in broad band and high frequency materials
·Economical
common mode EMI filtering
·Compact
size
Applications:
·Filtering
DC power on PC boards, especially in applications of greater than 3.0 amperes
·Filtering
common mode EMI on high
speed differential lines such as network and SCSI subsystems
·Cost
sensitive designs
·Applications
where low DCR is needed
Part & Test Specifications:
·Maximum
current ratings (I MAX) are determined by testing to a maximum temperature rise of 40
o
C with continuous operating
current
·Board
level components are rated up to a maximum of 75 volts
·Part
performance is shown with curves for Common, Open
and Normal Mode Impedances measured along two conductors.
Common Mode
Impedance is the impedance of EMI noise
conducted in the same direction along two conductors.
Open Circuit
Impedance is the impedance measured across a single leg of
the common mode choke.
Normal Mode
Impedance is the total impedance to the differential circuit (both out and back).
Tested with:
·HP4396A
(100KHz - 1.8 GHz) or HP8753 (to 6 GHz) Network/Spectrum Analyzer
·HP43961A
Impedance Test Kit
·HP16192A
Test Fixture or Inter-Continental Microwave custom fixtures
·HP16200A
DC Bias Adapter
·Philips
PM2811 DC Power
Supply
·Ambient
Temperature 23.5
o
C + 2
o
·Bandwidth
3 kHz
·Sweep
Time 423 ms
·Impedance
is rated at + 25% @100MHz
PART NUMBERING SYSTEM
CM
PRODUCT
SERIES CODE
2545
PART
SIZE CODE
X
RATED
CURRENT CODE
111
IMPEDANCE
VALUE CODE
B
PACKAGING
CODE
-
00
ADDITIONAL
DESCRIPTION
Ambient Operating Temperature Range: -55° C to +125° C
PART
NUMBER
Fig
#
A
mm
(inches)
6.30 + 0.25
(0.248 + 0.010)
6.30 + 0.25
(0.248 + 0.010)
6.30 + 0.25
(0.248 + 0.010)
6.30 + 0.25
(0.248 + 0.010)
B
mm
(inches)
11.38 + 0.25
(0.448 + 0.010)
11.38 + 0.25
(0.448 + 0.010)
11.38 + 0.25
(0.448 + 0.010)
11.38 + 0.25
(0.448 + 0.010)
C
mm
(inches)
9.32 + 0.25
(0.367 + 0.010)
9.32 + 0.25
(0.367 + 0.010)
9.32 + 0.25
(0.367 + 0.010)
9.32 + 0.25
(0.367 + 0.010)
D
mm
(inches)
7.62 + 0.10
(0.300 + 0.004)
7.62 + 0.10
(0.300 + 0.004)
7.62 + 0.10
(0.300 + 0.004)
7.62 + 0.10
(0.300 + 0.004)
E
mm
(inches)
2.54 + 0.10
(0.100 + 0.004)
2.54 + 0.10
(0.100 + 0.004)
2.54 + 0.10
(0.100 + 0.004)
2.54 + 0.10
(0.100 + 0.004)
IMPEDANCE (Z)
TYPICAL OHMS @
100MHz 500MHz 1GHz
110
260
175
DCR
MAX
OHMS
0.003
RATED I MAX
(continuous)
mA
10,000
*
*
CM2545X111B-00
CM2545X111R-00
CM2545X171B-00
CM2545X171R-00
1
2
110
260
175
0.003
10,000
1
170
235
320
0.003
10,000
2
170
235
320
0.003
10,000
*
High Frequency Material
Figure 1
Figure 2
18
STEWARD
- U.S.A.
• Telephone: 423/867-4100 • Fax 423/867-4102 • Internet: http://www.steward.com
SCOTLAND
• Telephone: 44-(0)1-506-414200 • Fax 44-(0)1-506-410694
SINGAPORE
• Telephone: (65)337-9667 • Fax (65)337-9686
400
CM2545X171B&R-00
Z, R, X
L
vs. Frequency
Impedance, Resistance, Inductive Reactance
400
CM2545X171B&R-00
Z vs. Frequency
Open, Common and Normal Mode
300
300
COMMON MODE
Impedance (W)
Impedance (W)
Z
200
R
100
X
L
0
1
10
100
1000
10000
Common
200
Open
100
Normal
0
1
10
100
1000
10000
Frequency (MHz)
Frequency (MHz)
500
CM2545X111B&R-00
Z, R, X
L
vs. Frequency
Impedance, Resistance, Inductive
500
CM2545X111B&R-00
Z vs. Frequency
Open, Common and Normal Mode
400
400
Impedance (W)
300
Z
200
R
100
X
L
0
1
10
100
1000
10000
Impedance (W)
300
200
Normal
100
Open
Common
0
Frequency (MHz)
1
10
100
1000
10000
Frequency (MHz)
Equivalent Circuts
Recommended Soldering Conditions
Land Patterns for Reflow Soldering
STEWARD
- U.S.A.
• Telephone: 423/867-4100 • Fax 423/867-4102 • Internet: http://www.steward.com
SCOTLAND
• Telephone: 44-(0)1-506-414200 • Fax 44-(0)1-506-410694
SINGAPORE
• Telephone: (65)337-9667 • Fax (65)337-9686
19