Picor Corporation www.picorpower.com QPI-1 Data Sheet Rev. 1.3 Page 1 of 4
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QPI-1L
QPI-1, 12 Amp Active EMI Filter
for DC-DC Converters
Description
The QPI-1 active EMI filter provides conducted
common-mode (CM) and differential-mode (DM)
attenuation from 150 kHz to 30 MHz. Active
filtering provides superior differential attenuation
at low frequencies. The product is designed for use
on a nominal 48 Vdc, (36-76 Vdc) bus. The QPI's 12A
rating supports multiple DC-DC converters drawing
up to 576W at nominal input voltage and 60C PCB
interface temperature.
Active filtering improves the transient response of
the filtered DC-DC converter(s) by virtually
eliminating ringing on the input in response to load
transients, as is often seen in passive filter solutions.
Units can be connected in series for higher
attenuation, or in parallel for higher current.
The QPI-1 is available in a 1.0" x 1.0"x 0.2" SiP
(System-in-Package) with LGA mounting. QPI-EVAL1
kits are available with a mounted QPI-1 and screw
or pin terminal options for vertical and a second
layer (mezzanine board) horizontal mounting.
Check www.picorpower.com for the evaluation
board data sheet.
Features QPI-1
>40 dB CM attenuation at 500 kHz
>80 dB DM attenuation at 500 kHz
80 Vdc (max input)
12 Amp rating
100 Vdc surge 100 ms
1,500 Vdc Hi-pot hold off to Shield Plane
1.0" x 1.0" x 0.2" SiP (System-in-Package)
SMT Land Grid Array
-40 to +100C PCB temperature (See Fig. 5)
Active filtering improves transient response
Efficiency 99%
Parallelable for higher currents
Connect in series for higher attenuation
Agency Approvals Pending
Typical Application
QPI Performance
QPI-
QPI+
BUS+
BUS-
QPI-1
SUPPLY-
SUPPLY+
Y-CAP/SHIELD PLANE
SHIELD PLANE
Converter
Cb*
Cc*
SAFETY COMMON
*NOTE: Cb REQUIRED FOR HIGH TRANSIENT LOADS
Cc IS CERAMIC, LOW ESR & ESL
47
F
10
F
TO CHASSIS OR
Figure 1 - QPI-1 circuit on input bus.
Figure 2 - Insertion loss curves showing common-mode and
differential -mode attenuation.
QuietPower
TM
Picor Corporation www.picorpower.com QPI-1 Data Sheet Rev. 1.3 Page 2 of 4
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Absolute Maximum Ratings
Exceeding these parameters may result in permanent damage to the product.
Electrical Characteristics
Parameter limits apply over the operating temp. range unless otherwise noted.
Pins
Parameter
Notes
Min
Max
Units
BUS+ to BUS-
Input voltage
Continuous
-0.5
80
Vdc
BUS+ to BUS-
Input voltage
100ms Transient
-0.5
100
Vdc
BUS+/BUS- to Shield Plane
BUS Inputs to Shield Hipot
Per test std
+/-1500
Vdc
QPI+ to QPI-
Input to output current
Continuous @ 25C
12
Adc
Package
Power Dissipation
VBUS = 48V, IBUS = 12 Adc, 25C
4.0
W
Package
Operating Temperature
PCB to QPI Interface
-40
100
C
Package
Thermal Resistance
Free Air
50
C/W
Package
Junction Temperature
Internal @ Pdmax and 15C/W
160
C
Package
Thermal Resistance
PCB Layout Fig. 6
15
C/W
Package
Storage Temperature
-40
125
C
Package
Re-flow Temperature
20 second exposure @
212
C
All Pins
ESD
HBM
+/-2
kV
Parameter
Notes
Min
Typ
Max
Units
BUS+ to BUS- Input Range
Measured at 10A (1)
30
80
Vdc
BUS+ to QPI+ Voltage Drop
Measured at 10A (1)
-300
mVdc
BUS- to QPI- Voltage Drop
Measured at 10A (1)
20
mVdc
Common Mode Insertion Loss
VBUS=48V Frequency=500kHz
45
dB
Differential Mode Insertion Loss
VBUS=48V Frequency=500kHz
90
dB
Input Bias Current at 80 Volts
Input current from BUS+ to BUS-
20
mA
Note 1: Refer to Figure 5 for current derating curve.
QPI-1: (bottom view)
Pad Designations
BUS+
BUS-
QPI+
QPI-
THERM1
SHIELD
THERM2
12,13,14
1,16,17
7,8,9
2,3,4
10
5,6
11
BUS-
BUS+
QPI+
SHIELD
QPI-
THERM1
THERM2
7
8
9
11
12
13
16
10
14
15
1
2
3
4
5
6
1, 15, 16 BUS- Negative bus voltage
2 - 4 QPI-
Negative input to the converter
5, 6 Shield
The shield connects to the
converter shield and Y capacitor common point
7- 9 QPI+
Positive input to the converter
10 THERM1
Internal connection must be
electrically floating but maximize copper
landing for heat sinking
11 THERM2
Internal connection must be
electrically floating but maximize copper
landing for heat sinking
12 - 14 BUS+ Positive bus voltage
Pin Description
QPI-IL (LGA)
Picor Corporation www.picorpower.com QPI-1 Data Sheet Rev. 1.3 Page 3 of 4
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Description
The QPI-1 is an active EMI filter providing common-
mode and differential-mode noise attenuation from
150 kHz to 30 MHz. Designed for the telecom bus
voltage range, the QPI supports the PICMG 3.0
specification for filtering system boards to the
EN 55022 limits.
The surface mount LGA, 1.0" x1.0" x 0.2"package
saves board space and eases manufacturing by
eliminating through-hole assembly.
The input of the converter will not exhibit the step-
load ringing associated with a passive design's
resonant frequencies and Qs. The QPI-1 attenuates
noise at all frequencies in the EN55022 band,
eliminating the empirical design work of passive
approaches and the uncertainty of whether a
passive design will actually work with the
converters.
The QPI-EVAL1 board allows vertical through-hole
mounting, freeing up additional PCB real estate as
well as providing horizontal mounting pins and
screw terminal connection options. The evaluation
board offers a plug-in board-level solution to
evaluate the QPI-1 in a power system to solve EMI
problems at the board and system level.
Test Example
Figure 3 shows the noise spectrum for a typical
converter compared the EN 55022 quasi-peak
detection limit taken using the standard
measurement conditions in the peak detect mode
for a conducted EMI test.
Figure 4 shows the effect of inserting the QPI-1 filter
between the DC bus and the converter input under
the same test conditions used in Figure 3.
The results show the QPI-1 is effective in reducing
the noise spectrum well below the EN 55022 quasi-
peak detection limit. Using the quasi-peak detection
measurement mode would lower the amplitudes by
the error factor this method introduces.
Thermal Considerations
The current derating curve shown in Figure 5 should
be used when the PCB temperature to which the
QPI-1 is mounted exceeds 60C. Refer to Figure 6 for
a PCB layout recommendation.
For example, the QPI-1, will filter 10A or up to 480W
of power from a 48 Vdc bus with an 80C PCB
interface temperature. It will provide filtering for
more than twice the 200W per board limit in the
PICMG 3.0 specification.
0
2
4
6
8
10
12
14
0
10
20
30
40
50
60
70
80
90
100
PCB to QPI Interface Temperature (Deg. C)
QPI Current (A)
Figure 3 Conducted EMI profile of a DC-DC Converter
without filter.
Figure 4 Conducted EMI profile of a DC-DC Converter
with QPI-1.
Figure 5 QPI-1 Current derating curve.
Picor Corporation www.picorpower.com QPI-1 Data Sheet P/N 26863 Rev. 1.3 11/03/10M
Vicor's comprehensive line of power solutions includes high-density AC-DC & DC-DC modules and accessory
components, fully configurable AC-DC & DC-DC power supplies, and complete custom power systems.
Information furnished by Vicor is believed to be accurate and reliable. However, no responsibility is assumed by Vicor for its
use. No license is granted by implication or otherwise under any patent or patent rights of Vicor. Vicor components are not
designed to be used in applications, such as life support systems, wherein a failure or malfunction could result in injury or
death. All sales are subject to Vicor's Terms and Conditions of Sale, which are available upon request.
Specifications are subject to change without notice.
Vicor Corporation
25 Frontage Road, Andover, MA, USA 01810
Tel: 800-735-6200 Fax: 978-475-6715
Email
Vicor Express: vicorexp@vicr.com
Technical Support: apps@vicr.com
0.175
0.135
0.135
0.113
0.135
0.125
0.135
0.125
R0.046
Pin 1
0.000
0.100
0.300
0.492
0.100
0.300
0.492
0.000
0.100
0.300
0.492
0.100
0.300
0.492
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Figure 6 Recommended LGA PCB Layout Pattern
Figure 7 LGA Pad Position Dimensions - inches
0.125
0.092
0.088
Edge Pad 1
0.125
0.046
0.092
2 Rounded Edge Pads
0.125
0.092
13 Edge Pads
Figure 8 LGA Pad Dimensions - inches
Files for PCB layouts available at picorpower.com.
Part Number
Description
QPI-1L
QPI-1 Land Grid Array
Ordering Information
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