QPI-4L ® QuietPower ™ 7 Amp Active EMI Filter for 48 V DC Bus Description Features The QPI-4 active EMI filter attenuates conducted common-mode (CM) and differential-mode (DM) noise over the CISPR22 frequency range of 150 kHz to 30 MHz. The product is designed for use on a 48 Vdc bus (36-76 Vdc). The QPI-4’s 7 A rating supports multiple DC-DC converter loads up to a PCB temperature of 60°C. At a 100°C PCB temperature the QPI-4 supports 6 A loads. Designed for the telecom and ITE bus range, the QPI-4 supports the PICMG® 3.0 specification for filtering system boards to the EN55022 Class B limits. • >40 dB CM attenuation at 250 kHz In comparison to passive solutions, the use of active filtering reduces the volume of the common-mode choke, providing a low profile, surface mount device. Smaller size saves valuable board real estate and the reduced height enhances airflow in blade applications. The QPI-4 is available in a 1.0" x 1.0" x 0.2" SiP (System in Package) with LGA mounting. QPI-4-EVAL1 kits are available for testing the QPI-4. The evaluation board has a mounted QPI-4 with screw terminals for quick in-circuit testing. • >70 dB DM attenuation at 250 kHz • 80 Vdc (max input) • 7 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 (LGA) • -40° to +100°C PCB temperature (See Fig. 5) • Active filtering reduces volume and height • Efficiency >99% at full load • Connect in series for higher attenuation • TÜV approved Applications • ATCA blades • Telecom base stations Check picorpower.com for the QPI-4-EVAL1 evaluation board and the QPI-AN1 Application Note. • IBA & distributed power Typical Application QPI Performance 10 Ω, 1/4 W Figure 1 - QPI basic input bus filter circuit. Read important note on page 3 for Layout and Circuit Considerations. Picor Corporation • www.picorpower.com Figure 2 - Attenuation curves showing common-mode and differential-mode attenuation. QPI-4L Data Sheet Rev. 3.0 Page 1 of 8 Absolute Maximum Ratings – Exceeding these parameters may result in permanent damage to the product. Pins Parameter Notes BUS+ to BUS- Input voltage Continuous -80 80 Vdc BUS+ to BUS- Input voltage 100ms transient -100 100 Vdc BUS+/BUS- to Shield Plane BUS inputs to Shield Hipot Per test std. QPI+ to QPI- Input to output current 10 seconds @ 25°C Package Power dissipation VBUS = 48 V, IBUS = 7 Adc, 60°C Package Operating temperature PCB to QPI Interface Package Thermal resistance Package Junction temperature Package Thermal resistance Package Storage temperature Min Max Units +/-1500 Vdc 10 Adc 2.0 W 100 °C Free air 50 °C/W Internal @ Pdmax and 15°C/W 130 °C 15 °C/W 125 °C -40 PCB layout (see Figs. 9 & 10) 1 -40 Package Re-flow temperature 20 second exposure @ 212 °C All Pins ESD HBM +/-2 kV Note 1 - Refer to Figures 9 & 10 for PCB layout guidelines to achieve this thermal resistance when re-flowed onto the PCB. Electrical Characteristics – Parameter limits apply over the operating temp. range unless otherwise noted. Parameter Notes Min A2 Typ 30 Max Units BUS+ to BUS- input range Measured at 7 BUS+ to QPI+ voltage drop Measured at 7 A2 80 Vdc -120 mVdc BUS- to QPI- voltage drop Measured at 7 A2 Common-mode insertion loss VBUS = 48 V frequency = 500 kHz 42 30 mVdc Differential-mode insertion loss VBUS = 48 V frequency = 500 kHz 72 dB Input bias current at 80 Volts Input current from BUS+ to BUS- 8 mA dB Note 2 - Refer to Figure 5 for current derating curve. THERM 1 THERM 2 9 10 11 QPI-4: (bottom view) 12 8 13 7 14 6 15 5 16 QPI+ SHIELD BUS+ BUS- BUS+ 3 4 2 QPI+ QPISHIELD BUS- 12,13,14 1,15,16 7,8,9 2,3,4 5,6 THERM 1 10 THERM 2 11 1 Pad Designations QPI- Pad Description BUS- Negative bus potential BUS+ Positive bus voltage QPI- Negative input to the converter QPI+ Positive input to the converter Picor Corporation • www.picorpower.com THERM1 THERM2 Internal connection must be electrically floating but maximize copper landing for heat sinking. Shield The shield connects to the converter shield and Y capacitor common point through RY. QPI-4L Data Sheet Rev. 3.0 Page 2 of 8 Applications Information The QPI-4 is an active EMI filter providing conducted common-mode and differential-mode attenuation from 150 kHz to 30 MHz. The QPI-4 attenuates noise at all frequencies covered by EN55022. Designers should be aware that to select and qualify an EMI filter they must test the filter in their equipment under the set up and conditions specified in the EMI standards that they are trying to meet. Filter performance is highly dependent on several factors and cannot be derived from the attenuation curves shown in Figure 2 alone. Performance is a complex function of filter element impedances and noise source impedances, which vary in magnitude and phase over the frequency spectrum. Measurements should be made in consultation with in-house compliance testing or an independent EMI test facility. Test Example Figures 3 and 4 show the before and after plots of a DC-DC converter noise profile to demonstrate the performance of the QPI-4. The plots were taken using the standard measurement technique and set up defined in CISPR22. The results show the total noise spectrum for a standard DC-DC converter under load compared to the EN55022 Class B Quasi-peak detection limit. Figure 3 – Conducted EMI profile of a DC-DC Converter without filter. The resulting plot in Figure 4 shows the QPI-4 is effective in reducing the total conducted noise spectrum measured pre-filter to well below the EN55022 Class B Quasi-peak detection limit. Picor Corporation • www.picorpower.com Figure 4 – Conducted EMI profile of a DC-DC Converter with QPI-4. Layout and Circuit Application of the QPI-4 requires PCB layout practices similar to those used with passive EMI filters. The circuit in Figure 6 and the PCB layout in Figures 9 & 10 should be used as a design guide to ensure successful application of the QPI-4. Refer to the application note QPI- AN1 for additional PCB layout recommendations. Note: For optimum performance of the QPI-1 it is critical to connect the QPI-1 Shield Plane (pins 5 & 6) to the converter EMI Shield Plane (common point of C1-C4 "Y" capacitors) thru RY as shown in Figure 6. If the safety earth-ground connection (chassis or case) is connected in the power conversion section of the PCB it should be at the input bus of the QPI-1 Shield Plane, shown as the optional connection in Figure 6. Connecting the converter EMI shield plane directly to chassis ground may degrade the QPI-1 attenuation performance. The typical value for RY is 10 Ohms. The recommended part is a 5% tolerance SMT1206 or similarly rated 0.25 W through-hole resistor. Some systems may require the converter positive or negative input or an output "terminal" to be connected to PE (Protective Earth) ground for safety or other considerations. When using the QPI in this situation this "terminal" must be connected to the converter shield plane created in the PCB layout under the converter. Because the PE earth path may pass excessive current under a fault condition the resistance of this path may be limited to a low resistance value. To meet the resistance requirement without degrading filter performance Ry can be replaced by a 4.7uH inductor rated for the fault current condition maintaining low power dissipation during a fault until the protection device clears. QPI-4L Data Sheet Rev. 3.0 Page 3 of 8 QPIs will filter multiple DC-DC converters up to the maximum current rating. The schematic in Figure 7 shows the required circuit for multiple DC-DC converters. The Shield Plane should be added under each converter as a common EMI Shield. Note that only a single RY is required in a multiple converter configuration. Thermal Considerations The current derating curve shown in Figure 5 should be used when the PCB temperature in close proximity of the QPI-4 exceeds 60°C. For example, the QPI-4 will support up to 6.5 A of current or 312 W from a 48 Vdc bus at an 80°C interface temperature. Temperature should be measured at the PCB interface to the QPI-4 on the Bus +/- pads or the QPI+/- pads. Refer to Figures 9, 10 & 12 for PCB layout recommendation. If higher attenuation is required, QPIs can be connected in series. Figure 8 shows the proper schematic for QPIs in series. Note that only one RY is required in this configuration. 8 QPI Current (A) The QPI can also be used to filter embedded or “down” converters made up of discrete components. Where ever possible a Shield Plane and Y-capacitor decoupling should be included in the embedded converter design. Follow the circuit and layout recommendations for a brick converter shown in Figures 7, 9 & 10. 6 4 2 0 0 10 20 30 40 50 60 70 80 90 100 PCB to QPI Interface Temperature (Deg. C) Figure 5 – QPI-4 current derating curve. PCB plane under converter VIN+ QPI+ BUS+ VOUT+ C1 BUS SUPPLY CB CIN QPI CONVERTER 47µF SHIELD BUS- QPI- VIN- VOUTC3 C2 C4 SHIELD RY Optional Connection Figure 6 – Recommended schematic for QPI. Values of CIN and C1-C4 should be the values recommended by the converter manufacturer. If the manufacturer does not specify a value for the Y-capacitors use 4.7nF. Ry=10Ω, 1/4 W. Picor Corporation • www.picorpower.com QPI-4L Data Sheet Rev. 3.0 Page 4 of 8 PCB plane under converter BUS+ BUS SUPPLY QPI+ VIN+ VOUT+ CIN1 CB QPI CONVERTER 47µF SHIELD BUS- QPI- VINC1 VOUT- C2 C3 C4 C7 C8 SHIELD RY Optional Connection 10 Ω, 1/4 W PCB plane under converter VIN+ VOUT+ CIN2 CONVERTER VINC5 VOUT- C6 SHIELD Additional Converters Figure 7 – Schematic for supporting multiple DC-DC converters. Note only a single RY is required. Use values recommended by converter manufacturer for CIN and Y-capacitors C1-C8. PCB plane under converter BUS+ BUS SUPPLY QPI+ BUS+ QPI+ VIN+ CB VOUT+ CIN QPI QPI CONVERTER 47 µF QPI- BUS- SHIELD SHIELD BUS- QPI- VINC1 VOUTC3 C2 C4 SHIELD RY Optional Connection 10 Ω, 1/4 W Figure 8 – Series connection of QPI for higher attenuation. Picor Corporation • www.picorpower.com QPI-4L Data Sheet Rev. 3.0 Page 5 of 8 Top Layer - Top View See note A Thermal 2 Thermal 1 Earth CB * * + CIN + * * * 5mm (0.200") Converter Shield Plane 5mm (0.200") Recommended Component Clearance (See note B) Figure 9 – Recommended layout for top layer of PCB. Pattern shows optional pins (*) dependent on converter used in design. (Actual size with half brick footprint) Note A: Some converters may radiate energy past the QPI into the input bus degrading noise reduction of the filter. To minimize the potential for this effect use a maximum feasible distance between the QPI and the converter in the layout. The input filter and any bulk hold up capacitors should be placed in this area. Note B: Hako de-soldering nozzle model no. A1137 and appropriated temperature controller can be used for removing and re-soldering SiP packages. Clearance around the SiP is a keep out zone for components as noted by the dashed line to use this tool. Components taller than 10mm (0.400") require 15mm (0.600") clearance from the SiP package edge. Thermal 2 Thermal 1 C1 QPI Shield C3 Shield Plane RY Bottom Layer - Top View C2 C4 Figure 10 – Recommended layout for bottom layer of PCB. Note location of RY. Picor Corporation • www.picorpower.com QPI-4L Data Sheet Rev. 3.0 Page 6 of 8 0.9843 0.1773 0.8000 45.000° 0.0625 0.492 0.441 0.400 0.0820 0.300 QPI SIP Package (Bottom View) 0.0820 0.9843 0.100 13 places 0.000 0.100 R0.0410 0.441 0.492 0.300 0.100 0.000 0.0200 0.100 0.492 0.441 0.1250 0.300 0.300 0.400 0.441 0.492 0.0820 2 places Figure 11 – QPI package dimensions and pad locations. QPI Package Outline THERM 2 0.4850 0.4410 0.3970 13 places THERM 1 0.050 0.050 0.0880 0.3000 QPI PCB Pad Pattern (Top View) 0.1000 R0.0440 0.492 BUS+ 0.0440 0.4410 0.4410 QPI+ 2 places 0.0000 0.0440 0.1000 0.050 0.050 0.0655 0.3000 SHIELD BUS- 0.3970 0.4850 0.3970 0.4410 0.4850 0.3000 0.1000 0.0000 0.1000 0.3000 0.4850 0.4410 0.3970 0.0880 0.050 0.1310 QPI- 0.050 Figure 12 – Recommended PCB solder mask dimensions and layout. Use 1.3mm clearance around shield pads 5 & 6 to adjacent lands. See Figures 9 & 10 for recommended connection layouts. Ordering Information Part Number Description QPI-4L QPI-4 Land Grid Array Picor Corporation • www.picorpower.com QPI-4L Data Sheet Rev. 3.0 Page 7 of 8 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 Picor Corporation • www.picorpower.com • QPI-4L Data Sheet Email Vicor Express: [email protected] Technical Support: [email protected] P/N 28050 Rev. 3.0 4/05