VIA PFM™ PFM4914xB6M48D0yzz ® S US C C NRTL US Isolated AC-DC Converter with PFC Features & Benefits Product Description • Universal input (85 to 264 VAC) The VIA PFM is a highly advanced 400 W AC-DC converter operating from a rectified universal AC input which delivers an isolated and regulated Safety Extra Low Voltage (SELV) 48 V secondary output. • 48 VOUT, regulated, isolated • 400 W maximum power • High efficiency This unique, ultra-low profile module incorporates AC-DC conversion, integrated filtering and transient surge protection in a chassis mount or PCB mount form factor. • Built-in EMI filtering • Chassis mount or board mount packaging options • Always-on, self-protecting converter control architecture • SELV Output The VIA PFM enables a versatile two-sided thermal strategy which greatly simplifies thermal design challenges. When combined with downstream Vicor DC-DC conversion components and regulators, the VIA PFM allows the Power Design Engineer to employ a simple, low-profile design which will differentiate his end-system without compromising on cost or performance metrics. • Two temperature grades including operation to -40°C • Robust package • Versatile thermal management • Safe and reliable secondary-side energy storage • High MTBF • 127 W/cubic inch power density • 4914 package • External rectification and transient protection required Typical Applications • Small cell base stations • Telecom switching equipment • LED lighting • Test and measurement equipment • 200 - 400 W Industrial power systems • Office equipment Size: 4.91 x 1.40 x .37 in 124.8 x 35.5 x 9.3 mm Part Ordering Information Product Function P F Package Length M PFM = Power Factor Module 4 9 Package Width 1 4 Package Type x Length in Width in B = Board VIA Inches x 10 Inches x 10 V = Chassis VIA Input Voltage B 6 Range Ratio M Output Voltage (Range) Max Output Current 4 D 8 Internal Reference VIA PFM™ Rev 1.3 vicorpower.com Page 1 of 24 07/2015 800 927.9474 0 Product Grade y Option Field z z 00 = Chassis/Always On C = -20 to 100°C 04 = Short Pin/Always On T = -40 to 100°C 08 = Long Pin/Always On PFM4914xB6M48D0yzz Typical PCB Mount Applications J1 48 V Filter ~ 85 264 Vac C4 + VIA PFM™ MOV ~ – + _ 48 V 3 A +OUT +IN D1 -IN PRM®/VTM® + _ 3.3 V 10 A PRM®/VTM® + _ 1.8 V 80 A + C1 -OUT The PCB terminal option allows mounting on an industry standard printed circuit board, with two different pin lengths. Vicor offers a variety of downstream DC-DC converters driven by the 48 V output of the VIA PFM. The 48 V output is usable directly by loads that are tolerant of the PFC line ripple, such as fans, motors, relays, and some types of lighting. Use downstream DC-DC Point of Load converters where more precise regulation is required. Parts List for Typical PCB Mount Applications J1 Delta 06AR2 EMI Filter Entry Module, C14 6 A 250 V 5 x 20 mm fuseholder F1 (mount in J1) Littelfuse 0216008.MXP 8 A 250 VAC 5 x 20 mm holder D1 Fairchild GBPC1210W 12 A 1000 V PTH Nichicon UVR1J472MRD 4700 µF 63 V 3.4 A 22 x 50 mm bent 90° x 2 pcs or C1 CDE 380LX472M063K022 4700 µF 63 V 4.9 A 30 x 30 mm snap x 2 pcs or Sic Safco Cubisic LP A712121 10,000 µF 63 V 6.4 A 45 x 75 x 12 mm rectangular C4 Panasonic ECQ-U2A474ML 0.47 µF 275 V MOV Littelfuse TMOV20RP300E VARISTOR 10 kA 300 V 250 J 20 mm VIA PFM™ Rev 1.3 vicorpower.com Page 2 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Typical Chassis Mount Applications J1 48 V Filter 85 264 Vac C4 +OUT +IN D1 ~ + ~ – Fan VIA PFM™ MOV C1 -OUT -IN 8 Relays 8 16 Dispensors Controller Coin Box The VIA PFM is available in Chassis Mount option, saving the cost of a PCB and allowing access to both sides of the power supply for cooling. The parts list below minimizes the number of interconnects required between necessary components, and selects components with terminals traditionally used for point to point chassis wiring. Parts List for Typical Chassis Mount Applications J1 Delta 06AR2 EMI Filter Entry Module, C14 6 A 250 V 5 x 20 mm fuseholder F1 (mount in J1) Littelfuse 0216008.MXP 8 A 250 VAC 5 x 20 mm holder D1 Fairchild GBPC1210FS 12 A 1000 V 0.25” QC TERMINAL C1 UCC E32D630HPN103MA67M 10,000 µF, 63 V 7.4 A, 35 x 67 mm screw terminal or Kemet ALS30A103DE063, 10,000 µF 63 V 10.8 A 36 x 84 mm screw terminal C4 Panasonic ECQ-U2A474ML 0.47 µF 275 V MOV Littelfuse TMOV20RP300E VARISTOR 10 kA 300 V 250 J 20 mm VIA PFM™ Rev 1.3 vicorpower.com Page 3 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Pin Configuration 1 2 TOP VIEW +IN A C +OUT –IN B D –OUT 4914 VIA PFM - Chassis Mount - Terminals Up 1 2 TOP VIEW –IN B D –OUT +IN A C +OUT 4914 VIA PFM - PCB Mount - Pins Down Please note that these Pin drawings are not to scale. Pin Descriptions Pin Number Signal Name Type Function A1 +IN INPUT POWER Positive input power terminal B1 –IN INPUT POWER RETURN Negative input power terminal C2 +OUT OUTPUT POWER Positive output power terminal D2 –OUT OUTPUT POWER RETURN Negative output power terminal VIA PFM™ Rev 1.3 vicorpower.com Page 4 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Absolute Maximum Ratings The absolute maximum ratings below are stress ratings only. Operation at or beyond these maximum ratings can cause permanent damage to the device. Parameter Comments Min Max Unit Input voltage +IN to –IN 1 ms max 0 600 Vpk Input voltage (+IN to -IN) Continuous, Rectified 0 275 VRMS -0.5 58 VDC Output voltage (+Out to -Out) Output current 0.0 12.4 A Operating junction temperature T-Grade -40 125 °C Storage temperature T-Grade -40 125 °C Dielectric Withstand* See note below Input-Case Basic Insulation 2121 Vdc Input-Output Reinforced Insulation 4242 Vdc Output-Case Functional Insulation 707 Vdc 10.00 500 8.00 400 6.00 300 4.00 200 2.00 100 0.00 0 -60 -40 -20 0 20 40 60 80 Case Temperature (°C) Current Power Safe Operating Area VIA PFM™ Rev 1.3 vicorpower.com Page 5 of 24 07/2015 800 927.9474 100 Output Power (W) Output Current (A) * Please see Dielectric Withstand section. See page 18. PFM4914xB6M48D0yzz Electrical Specifications Specifications apply over all line and load conditions, 50 Hz and 60 Hz line frequencies, TJ = 25°C, unless otherwise noted. Boldface specifications apply over the temperature range of the specified product grade. COUT is 10,000 µF +/- 20% unless otherwise specified. Attribute Symbol Conditions / Notes Min Typ Max Unit 264 VRMS 600 V 148 VRMS Power Input Specification Input voltage range, continuous operation VIN Input voltage range, transient, non-operational (peak) VIN Input voltage cell reconfiguration low-to-high threshold VIN-CR+ Input voltage cell reconfiguration high-to-low threshold VIN-CR- 85 1 ms 145 132 Input current (peak) IINRP Source line frequency range fline Power factor PF Input power >200 W Input inductance, maximum LIN Differential mode inductance, common mode inductance may be higher. See section "Source Inductance Considerations" on page 16. Input capacitance, maximum CIN After bridge rectifier, between +IN and - IN 135 See Figure 8, Startup Waveforms 47 VRMS 12 A 63 Hz 0.96 1 mH 1.5 µF 7 W 50 V No Load Specification Input power – no load, maximum PNL Power Output Specification Output voltage set point VOUT VIN = 230 Vrms, 100% Load 46 Output voltage, no load VOUT-NL Over all operating steady state line conditions 42 52 V Output voltage range (transient) VOUT Non-faulting abnormal line and load transient conditions 30 57.6 V Output power POUT See SOA on Page 4 400 W VIN = 230 V, full load, exclusive of input rectifier losses Efficiency h 90.5 48 92 % 85 V < VIN < 264 V, full load, exclusive of input rectifier losses 90 % 85 V < VIN < 264 V, 75% load, exclusive of input rectifier losses 90 % Output voltage ripple, switching frequency VOUT-PP-HF Over all operating steady-state line and load conditions, 20 MHz BW, measured at C3, Figure 5 200 2000 mV Output voltage ripple line frequency VOUT-PP-LF Over all operating steady-state line and load conditions, 20 MHz BW 3.0 7.0 V Output capacitance (external) COUT-EXT Allows for ±20% capacitor tolerance 15000 µF 6800 Output turn-on delay TON From VIN applied 500 1000 ms Start-up setpoint aquisition time TSS Full load 500 1000 ms Cell reconfiguration response time TCR Full load 5.5 11 ms 20 % 600 ms Voltage deviation (transient) %VOUT-TRANS -37.5 Recovery time TTRANS Line regulation %VOUT-LINE Full load 3 % Load regulation %VOUT-LOAD 10% to 100% load 3 % SOA 8.33 A 20 ms duration, average power ≤POUT, max 12.5 A Output current (continuous) Output current (transient) IOUT IOUT-PK 300 VIA PFM™ Rev 1.3 vicorpower.com Page 6 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Electrical Specifications (Cont.) Specifications apply over all line and load conditions, 50 Hz and 60 Hz line frequencies, TJ = 25°C, unless otherwise noted. Boldface specifications apply over the temperature range of the specified product grade. COUT is 10,000 µF +/- 20% unless otherwise specified. Attribute Symbol Conditions / Notes Min Typ Max Unit 74 83 VRMS Powertrain Protections Input undervoltage turn-on VIN-ULVO+ Input undervoltage turn-off VIN-ULVO- Input overvoltage turn-on VIN-ULVO- Input overvoltage turn-off VIN-ULVO+ Output overvoltage threshold VOUT-ULVO+ Upper start / restart temperature threshold (case) TCASE-OTP- See Timing Diagram See Timing Diagram Instantaneous, latched shutdown 65 71 VRMS 265 270 VRMS 58 273 287 VRMS 61 64 V 100 °C Overtemperature shutdown threshold (junction) TJ-OTP+ 125 °C Overtemperature shutdown threshold (case) TCASE-OTP+ 110 °C Overcurrent blanking time TOC Based on line frequency Input overvoltage response time TPOVP Input undervoltage response time TUVLO Output overvoltage response time TSOVP 400 460 550 ms 40 ms Based on line frequency 200 ms Powertrain on 30 ms Short circuit response time TSC Powertrain on, operational state 270 µs Fault retry delay time TOFF See Timing Diagram 10 s Output power limit PPROT 50% overload for 20 ms typ allowed VIA PFM™ Rev 1.3 vicorpower.com Page 7 of 24 07/2015 800 927.9474 400 W Output Input VIA PFM™ Rev 1.3 vicorpower.com Page 8 of 24 07/2015 800 927.9474 ILOAD VOUT EN VIN-RMS tON ≈30VRMS VIN-UVLO+ 1 Input Power On & UV Turn-on VOUT-NL VOUT 2 3 Full 10% Load Load Applied Applied tEN-DIS 4 EN Forced Low tON 5 EN High tSS VIN-CR+ tPOVP tON tSS VIN-OVLO- 7 8 Input Input OV OV Turn-off Turn-on VIN-OVLO+ tCR 6 Range Change LO to HI tCR VIN-CR- 9 Range Change HI to LO tUVLO VIN-UVLO- 11 12 Load Input Power Step Off & UV Turn-off tTRANS (2 places) 10 Load Dump PFM4914xB6M48D0yzz Timing diagram Output Input VIA PFM™ Rev 1.3 vicorpower.com Page 9 of 24 07/2015 800 927.9474 ILOAD VOUT EN VIN-RMS tSS tON VIN-UVLO+ 13 Input Power ON & UV Turn-on tOFF+tON tOC tOC 14 Output OC Fault tOFF+tON tOC 15 Output OC Recovery )) tSOVP )) )) * )) )) )) )) )) )) VOUT-OVLO+ * 18 Output OVP Fault )) tON 17 Toggle EN (Output OVP Recovery) )) )) 16 Output OVP Fault VIN-UVLO+ tON 19 Recycle Input Power (Output OVP Recovery) tSC tOFF+tON 20 Output SC Fault tOFF+tON 21 Output SC Recovery ≥tOFF+tON VIN-UVLO- 22 23 24 OT Fault Line Input & Drop-Out Power Recovery Off & UV Turn-off PFM4914xB6M48D0yzz Timing diagram (Cont.) PFM4914xB6M48D0yzz No Load Power Dissipation (W) Application Characteristics Typical characteristics at 20°C with 10,000 µF bulk electrolytic capacitor unless otherwise noted. 93.2 Efficiency (%) 93.0 92.8 92.6 92.4 92.2 92.0 91.8 91.6 85 105 125 145 165 185 205 225 245 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 85 265 105 125 Figure 1 — Full load efficiency vs. line voltage 165 185 205 225 245 265 Figure 2 — Typical no load power dissipation vs. VIN , module enabled 1.00 800 0.98 700 0.96 Power Factor Current (mA) 145 Input Line Voltage Input Line Voltage 600 500 400 300 0.94 0.92 0.90 0.88 0.86 200 0.84 100 0.82 0.80 0 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 0 100 200 300 400 Output Power (W) 230 V, 50 Hz 1/3x EN61000-3-2, Class A EN61000-3-2, Class D VIN: 120 V/60 Hz 230 V/50 Hz 100 V/50 Hz Figure 3 — Typical input current harmonics, full load vs. VIN using typical applications circuit on pages 2 & 3 Figure 4 — Typical power factor vs. VIN and IOUT using typical applications circuit on pages 2 & 3 Figure 5 — Typical switching frequency output voltage ripple waveform, TCASE = 30ºC, VIN = 230 V, IOUT = 8.3 A, no external ceramic capacitance, 20 MHZ BW Figure 6 — Typical line frequency output voltage ripple waveform, TCASE = 30ºC, VIN = 230 V, IOUT = 8.3 A, COUT = 10,000 µF. 20 MHZ BW VIA PFM™ Rev 1.3 vicorpower.com Page 10 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Application Characteristics (Cont.) Typical characteristics at 20°C with 10,000 µF bulk electrolytic capacitor unless otherwise noted. Figure 7 — Typical output voltage transient response, TCASE = 30ºC, VIN = 230 V, IOUT = 8.3 A, 2.1 A COUT = 10,000 µF Figure 8 — Typical startup waveform, application of VIN , RLOAD = 5.7 Ω, COUT = 10,000 µF Figure 9 — 230 V, 120 V range change transient response 16.7 A, IOUT = 8.3 A, COUT = 10,000 µF Figure 10 — Line drop out, 230 V 50 Hz, 0° phase, IOUT = 8.3 A, COUT = 10,000 µF Figure 11 — Line drop out, 230 V50 Hz, 90° phase, VIN = 230 V, 50 Hz, IOUT = 8.3 A, COUT = 10,000 µF Figure 12 — Typical line current waveform, VIN = 120 V, 60 HZ IOUT = 8.3 A, COUT = 10,000 µF VIA PFM™ Rev 1.3 vicorpower.com Page 11 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Application Characteristics (Cont.) Typical characteristics at 20°C with 10,000 µF bulk electrolytic capacitor unless otherwise noted. Marker 2 [T1] Det 61.80 dB V Att 20 dB 999.00000000 kHz INPUT 2 100 MA Trd Det 55022RED Att 20 dB ResBW 9 kHz Meas T 20 ms Unit dB V 10 MHz 2 [T1] 61.80 dB V 1 MHz INPUT 2 100 MA Trd 55022RED ResBW 9 kHz Meas T 20 ms Unit 1 MHz dB V 10 MHz 999.00000000 kHz 1 [T1] 90 80 76.61 dB V 198.00000000 kHz SGL 22QPA 1 90 SGL 80 1MA 22QPA 1MA 70 70 2 22QPB 22QPB 60 60 50 50 40 40 30 30 17.Mar 2015 08:49 20 Date: 150 kHz 30 MHz 17.MAR.2015 Date: 08:49:31 Figure 13 — Typical EMI Spectrum, Peak Scan, 90% load, 115 VIN, COUT = 10,000 µF, No Inlet Filter, C4 Marker 2 [T1] Det 61.57 dB V Att 20 dB 978.00000000 kHz INPUT 2 20.Mar 2015 14:59 20 150 kHz 100 MA Trd 14:59:08 Figure 14 — Typical EMI Spectrum, Peak Scan, 90% load, 115 VIN, COUT = 10,000 µF using Typical Chassis Mount Application Circuit 55022RED Det Marker 1 [T1] ResBW 9 kHz Meas T 20 ms Unit dB V 10 MHz 2 [T1] 61.57 dB V 1 MHz 30 MHz 20.MAR.2015 57.24 dB V Att 20 dB 158.00000000 kHz INPUT 2 100 MA Trd 9 kHz Meas T 20 ms Unit dB V 10 MHz 1 [T1] 57.24 dB V 1 MHz 978.00000000 kHz 1 [T1] 90 80 158.00000000 kHz 73.94 dB V 230.00000000 kHz SGL 22QPA 1 55022RED ResBW 2 [T1] 90 80 1MA 70 54.30 dB V 19.90300000 MHz SGL 22QPA 1MA 70 2 22QPB 22QPB 60 60 1 50 50 40 40 30 30 2 17.Mar 2015 09:21 30 MHz 150 kHz 09:21:58 Date: 94 50 92 45 90 40 88 35 86 30 84 25 PD 82 20 Power Dissipation (W) Efficiency (%) Figure 15 — Typical EMI Spectrum, Peak Scan, 90% load, 230 VIN, COUT = 10,000 µF, No Inlet Filter, C4 94 50 92 45 90 40 88 35 86 30 84 20 15 80 78 10 78 2 3 4 5 6 7 8 9 10 0 1 2 3 Load Current (A) VIN: 25 PD 82 15 1 15:36:59 Figure 16 — Typical EMI Spectrum, Peak Scan, 90% load, 230 VIN, COUT = 10,000 µF using Typical Chassis Mount Application Circuit 80 0 30 MHz 20.MAR.2015 4 5 6 7 8 9 Load Current (A) 85 V 115 V 230 V Eff 85 V 115 V 230 V P Diss Figure 17 — VIN to VOUT efficiency and power dissipation vs. VIN and IOUT , TCASE = -40ºC VIN: 85 V 115 V 230 V Eff 85 V 115 V 230 V P Diss Figure 18 — VIN to VOUT efficiency and power dissipation vs. VIN and IOUT , TCASE = 20ºC VIA PFM™ Rev 1.3 vicorpower.com Page 12 of 24 07/2015 800 927.9474 Power Dissipation (W) 17.MAR.2015 20.Mar 2015 15:36 20 150 kHz Efficiency (%) 20 Date: PFM4914xB6M48D0yzz 94 50 92 45 90 40 88 35 86 30 84 25 PD 82 20 80 Power Dissipation (W) Efficiency (%) Application Characteristics (Cont.) Typical characteristics at 20°C with 10,000 µF bulk electrolytic capacitor unless otherwise noted. 15 78 10 0 1 2 3 4 5 6 7 8 9 Load Current (A) VIN: 85 V 115 V 230 V Eff 85 V 115 V 230 V P Diss Figure 19 — VIN to VOUT efficiency and power dissipation vs. VIN and IOUT , TCASE = 85ºC VIA PFM™ Rev 1.3 vicorpower.com Page 13 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz General Characteristics Specifications apply over all line and load conditions, 50 Hz and 60 Hz line frequencies, TC = 25°C, unless otherwise noted. Boldface specifications apply over the temperature range of the specified Product Grade. Attribute Symbol Conditions / Notes Min Typ Max Unit Mechanical Length L 124.8 / [4.91] mm / [in] Width W 35.5 / [1.40] mm / [in] Height H Volume Vol Weight W Without heatsink 9.3 / [0.37] mm / [in] 42.0 / [2.56] cm3/ [in3] 156 / [5.5] g / [oz] Pin material C145 copper, half hard Underplate Low stress ductile nickel 50 100 µin Palladium 0.8 6 µin Soft Gold 0.12 2 µin C - Grade, see derating curve in SOA -20 100 °C T - Grade, see derating curve in SOA -40 100 °C Pin finish Thermal Operating case temperature TC Thermal resistance, junction to case, top RJC_TOP 1.04 °C/W Thermal resistance, junction to case, bottom RJC_BOT 1.83 °C/W RHOU 0.15 °C/W 32 J/K Coupling thermal resistance, top to bottom of case, internal Shell Thermal capacity Thermal design See Thermal Design on Page 17 Assembly ESD rating ESDHBM Human Body Model, JEDEC JESD 22-A114C.01 ESDMM Machine Model, JEDEC JESD 22-A115B N/A ESDCDM Charged Device Model, JEDEC JESD 22-C101D 200 1,000 V Safety cTÜVus; EN 60950-1 Agency approvals/standards cURus; UL 60950-1 CE Marked for Low Voltage Directive and RoHS Recast Directive, as applicable Touch Current measured in accordance with IEC 60990 using measuring network Figure 3 (VIA PFM only) EMI/EMC Compliance FCC Part 15, EN55022, CISPR22: 2006 + A1: 2007, Conducted Emissions Class B Limits - with –OUT connected to GND EN61000-3-2: 2009, Harmonic Current Emissions Class A VIA PFM™ Rev 1.3 vicorpower.com Page 14 of 24 07/2015 800 927.9474 0.5 mA PFM4914xB6M48D0yzz General Characteristics (Cont.) Specifications apply over all line and load conditions, 50 Hz and 60 Hz line frequencies, TC = 25°C, unless otherwise noted. Boldface specifications apply over the temperature range of the specified Product Grade. Attribute Symbol Conditions / Notes Min EMI/EMC Compliance (cont.) EN61000-3-3: 2005, Voltage Changes & Flicker PST <1.0; PLT <0.65; dc <3.3% dmax <6% EN61000-4-4: 2004, Electrical Fast Transients Level 2, Performance Criteria A EN61000-4-5: 2006, Surge Immunity Level 3, Immunity Criteria A, external TMOV required EN61000-4-6: 2009, Conducted RF Immunity Level 2, 130 dBµV (3.0 VRMS) EN61000-4-8: 1993 + A1 2001, Power Frequency H-Field 10A/m, continuous field Level 3, Performance Criteria A EN61000-4-11: 2004, Voltage Dips & Interrupts Class 2, Performance Criteria A Dips, Performance Criteria B Interrupts VIA PFM™ Rev 1.3 vicorpower.com Page 15 of 24 07/2015 800 927.9474 Typ Max Unit PFM4914xB6M48D0yzz Product Details and Design Guidelines Input Fuse Selection VI Brick products are not internally fused in order to provide flexibility in configuring power systems. Input line fusing is recommended at system level, in order to provide thermal protection in case of catastrophic failure. The fuse shall be selected by closely matching system requirements with the following characteristics: Building Blocks and System Designs +IN ~ + ~ – Recommended fuse: Change to 216 Series Littlefuse 8A or lower +OUT current rating (usually greater than the VIA PFM maximum current at lowest input voltage) Maximum voltage rating (usually greater than the maximum possible input voltage) VIA PFM™ MOV -IN -OUT Holdup Capacitor Ambient temperature Breaking capacity per application requirements Nominal melting I2t Figure 20 – 400 W Universal AC-to-DC Supply Source Inductance Considerations The VIA PFM is a high efficiency AC-to-DC converter, operating from a universal AC input to generate an isolated SELV 48 VDC output bus with power factor correction. It is the key component of an AC-to-DC power supply system such as the one shown in Figure 20 above. The input to the VIA PFM is a rectified sinusoidal AC source with a power factor maintained by the module with harmonics conforming to IEC 61000-3-2. Internal filtering enables compliance with the standards relevant to the application (Surge, EMI, etc.). See EMI/EMC Compliance standards on Page 13. The module uses secondary-side energy storage (at the SELV 48 V bus) to maintain output hold up through line dropouts and brownouts. Downstream regulators also provide tighter voltage regulation, if required. Traditional PFC Topology Full Wave Rectifier EMI/TVS Filter Isolated DC / DC 48 V Bus Converter Figure 21 – Traditional PFC AC-to-DC supply To cope with input voltages across worldwide AC mains (85 – 264 Vac), traditional AC-DC power supplies (Figure 21) use two power conversion stages: 1) a PFC boost stage to step up from a rectified input as low as 85 Vac to ~380 Vdc; and 2) a DC-DC down converter from 380 Vdc to a 48 V bus. The efficiency of the boost stage and of traditional power supplies is significantly compromised operating from worldwide AC lines as low as 85 Vac. Adaptive Cell™ Topology With its single stage Adaptive Cell™ topology, the VIA PFM enables consistently high efficiency conversion from worldwide AC mains to a 48 V bus and efficient secondary-side power distribution. The VIA PFM Powertrain uses a unique Adaptive Cell Topology that dynamically matches the powertrain architecture to the AC line voltage. In addition the VIA PFM uses a unique control algorithm to reduce the AC line harmonics yet still achieve rapid response to dynamic load conditions presented to it at the DC output terminals. Given these unique power processing features, the VIA PFM can expose deficiencies in the AC line source impedance that may result in unstable operation if ignored. It is recommended that for a single VIA PFM, the line source inductance should be no greater than 1 mH for a universal AC input of 100 - 240 V. If the VIA PFM will be operated at 240 V nominal only , the source impedance may be increased to 2 mH. For either of the preceding operating conditions it is best to be conservative and stay below the maximum source inductance values. When multiple VIA PFM’s are used on a single AC line, the inductance should be no greater than 1 mH/N, where N is the number of VIA PFM’s on the AC branch circuit, or 2 mH/N for 240 Vac operation. It is important to consider all potential sources of series inductance including and not limited to, AC power distribution transformers, structure wiring inductance, AC line reactors, and additional line filters. Non-linear behavior of power distribution devices ahead of the VIA PFM may further reduce the maximum inductance and require testing to ensure optimal performance. If the VIA PFM is to be utilized in large arrays, the VIA PFMs should be spread across multiple phases or sources thereby minimizing the source inductance requirements, or be operated at a line voltage close to 240 Vac. Vicor Applications should be contacted to assist in the review of the application when multiple devices are to be used in arrays. Fault Handling Input Undervoltage (UV) Fault Protection The input voltage is monitored by the micro-controller to detect an input under voltage condition. When the input voltage is less than the VIN-UVLO-, a fault is detected, the fault latch and reset logic disables the modulator, the modulator stops powertrain switching, and the output voltage of the unit falls. After a time tUVLO, the unit shuts down. Faults lasting less than tUVLO may not be detected. Such a fault does not go through an auto-restart cycle. Once the input voltage rises above VINUVLO+, the unit recovers from the input UV fault, the powertrain resumes normal switching after a time tON and the output voltage of the unit reaches the set-point voltage within a time tSS. VIA PFM™ Rev 1.3 vicorpower.com Page 16 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Overcurrent (OC) Fault Protection The unit’s output current, determined by VEAO, VIN_B and the primaryside sensed output voltage is monitored by the microcontroller to detect an output OC condition. If the output current exceeds its current limit, a fault is detected, the reset logic disables the modulator, the modulator stops powertrain switching, and the output voltage of the module falls after a time tOC. As long as the fault persists, the module goes through an auto-restart cycle with off time equal to tOFF + tON and on time equal to tOC. Faults shorter than a time tOC may not be detected. Once the fault is cleared, the module follows its normal start up sequence after a time tOFF. Short Circuit (SC) Fault Protection The microcontroller determines a short circuit on the output of the unit by measuring its primary sensed output voltage and EAO. Most commonly, a drop in the primary-sensed output voltage triggers a short circuit event. The module responds to a short circuit event within a time tSC. The module then goes through an auto restart cycle, with an off time equal to tOFF + tON and an on time equal to tSC, for as long as the short circuit fault condition persists. Once the fault is cleared, the unit follows its normal start up sequence after a time tOFF. Faults shorter than a time tSC may not be detected. Temperature Fault Protection The microcontroller monitors the temperature within the VIA PFM. If this temperature exceeds TJ-OTP+, an overtemperature fault is detected, the reset logic block disables the modulator, the modulator stops the powertrain switching and the output voltage of the VIA PFM falls. Once the case temperature falls below TCASE-OTP-, after a time greater than or equal to tOFF, the converter recovers and undergoes a normal restart. For the C-grade version of the converter, this temperature is 75°C. Faults shorter than a time tOTP may not be detected. If the temperature falls below TCASE-UTP-, an undertemperature fault is detected, the reset logic disables the modulator, the modulator stops powertrain switching and the output voltage of the unit falls. Once the case temperature rises above TCASEUTP, after a time greater than or equal to tOFF, the unit recovers and undergoes a normal restart. Output Filtering The VIA PFM requires an output bulk capacitor in the range of 6,800 μF 2 2 C = 2*POUT*(0.005+td) / (V2 – V1 ) where: C VIA PFM’s output bulk capacitance in farads td Hold-up time in seconds POUT VIA PFM’s output power in watts V2 Output voltage of VIA PFM’s converter in volts Downstream regulator undervoltage turn off (volts) V1 –OR– POUT / IOUT-PK, whichever is greater. to 15,000 μF for proper operation of the PFC front-end. A minimum 10,000 μF is recommended for full rated output. Capacitance can be reduced proportionally for lower maximum loads. The output voltage has the following two components of voltage ripple: 1) Line frequency voltage ripple: 2*fLINE Hz component 2) Switching frequency voltage ripple: 1 MHz module switching frequency component (see Figure 5). Line Frequency Filtering Output line frequency ripple depends upon output bulk capacitance. Output bulk capacitor values should be calculated based on line frequency voltage ripple. High-grade electrolytic capacitors with adequate ripple current ratings, low ESR and a minimum voltage rating of 63 V are recommended. lPK Output Overvoltage Protection (OVP) The microcontroller monitors the primary sensed output voltage to detect output OVP. If the primary sensed output voltage exceeds VOUTOVLO+, a fault is latched, the logic disables the modulator, the modulator stops powertrain switching, and the output voltage of the module falls after a time tSOVP. Faults shorter than a time tSOVP may not be detected. This type of fault is a latched fault and requires that 1) the EN pin be toggled or 2) the input power be recycled to recover from the fault. Hold-up Capacitance The VIA PFM uses secondary-side energy storage (at the SELV 48 V bus) and optional PRM® regulators to maintain output hold up through line dropouts and brownouts. The module’s output bulk capacitance can be sized to achieve the required hold up functionality. lPK/2 loutDC lfLINE Figure 22 – Output current waveform Hold-up time depends upon the output power drawn from the VIA PFM based AC-to-DC front end and the input voltage range of downstream DC-to-DC converters. The following formula can be used to calculate hold-up capacitance for a system comprised of VIA PFM and a downstream regulator: VIA PFM™ Rev 1.3 vicorpower.com Page 17 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Based on the output current waveform, as seen in Figure 22, the following formula can be used to determine peak-to-peak line frequency output voltage ripple: VPPl ~ = to simplify the thermal solution into a roughly equivalent circuit where power dissipation is modeled as a current source, isothermal surface temperatures are represented as voltage sources and the thermal resistances are represented as resistors. Figure 23 shows the “thermal circuit” for the VIA module. 0.2 * POUT / (VOUT * fLINE * C) where: VPPl Output voltage ripple Peak-to-peak line frequency POUT Average output power – Output voltage set point, nominally 48 V fLINE Frequency of line voltage C Output bulk capacitance IDC Maximum average output current IPK Peak-to-peak line frequency output current ripple – + Switching Frequency Filtering This is included within the VIA PFM. No external filtering is necessary for most applications. For the most noise sensitive applications, a common mode choke followed by two caps to PE GND will reduce switching noise further. s Figure 23 – Double sided cooling VIA thermal model In this case, the internal power dissipation is PDISS, RJC_TOP and RJC_BOT are thermal resistance characteristics of the VIA module and the top and bottom surface temperatures are represented as TC_TOP, and TC_BOT. It interesting to notice that the package itself provides a high degree of thermal coupling between the top and bottom case surfaces (represented in the model by the resistor RHOU). This feature enables two main options regarding thermal designs: Single side cooling: the model of Figure 23 can be simplified by calculating the parallel resistor network and using one simple thermal resistance number and the internal power dissipation curves; an example for bottom side cooling only is shown in Figure 24. EMI Filtering and Transient Voltage Suppression EMI Filtering The VIA PFM with PFC is designed such that it will comply with EN55022 Class B for Conducted Emissions with a commercially available off-the-shelf EM filter. The emissions spectrum is shown in Figures 13 - 16. If one of the outputs is connected to earth ground, a small output common mode choke is also recommended. RJC + TC_BOT EMI performance is subject to a wide variety of external influences such as PCB construction, circuit layout etc. As such, external components in addition to those listed herein may be required in specific instances to gain full compliance to the standards specified. Transient Voltage Suppression The VIA PFM contains line transient suppression circuitry to meet specifications for surge (i.e. EN61000-4-5) and fast transient conditions (i.e. EN61000-4-4 fast transient/“burst”). Thermal Considerations The VIA™ package provides effective conduction cooling from either of the two module surfaces. Heat may be removed from the top surface, the bottom surface or both. The extent to which these two surfaces are cooled is a key component for determining the maximum power that can be processed by a VIA, as can be seen from specified thermal operating area on Page 4. Since the VIA has a maximum internal temperature rating, it is necessary to estimate this internal temperature based on a system-level thermal solution. To this purpose, it is helpful – 0.8 * POUT / VOUT s TC_BOT RJC_BOT PDISS In certain applications, the choice of bulk capacitance may be determined by hold-up requirements and low frequency output voltage filtering requirements. Such applications may use the greater capacitance value determined from these requirements. The ripple current rating for the bulk capacitors can be determined from the following equation: ~ = TC_TOP RHOU VOUT Iripple + RJC_TOP PDISS s Figure 24 – Single-sided cooling VIA thermal model In this case, RJC can be derived as following: RJC = (RJC_TOP + RHOU) • RJC_BOT RJC_TOP + RHOU + RJC_BOT VIA PFM™ Rev 1.3 vicorpower.com Page 18 of 24 07/2015 800 927.9474 s PFM4914xB6M48D0yzz Double side cooling: while this option might bring limited advantage to the module internal components (given the surfaceto-surface coupling provided), it might be appealing in cases where the external thermal system requires allocating power to two different elements, like for example heatsinks with independent airflows or a combination of chassis/air cooling. Powering a Constant Power Load When the output voltage of the VIA PFM module is applied to the input of the downstream regulator, the regulator turns on and acts as a constant-power load. When the module’s output voltage reaches the input undervoltage turn on of the regulator, the regulator will attempt to start. However, the current demand of the downstream regulator at the undervoltage turn-on point and the hold-up capacitor charging current may force the VIA PFM into current limit. In this case, the unit may shut down and restart repeatedly. In order to prevent this multiple restart scenario, it is necessary to delay enabling a constant-power load when powered up by the upstream VIA PFM until after the output set point of the VIA PFM is reached. This can be achieved by 1. keeping the downstream constant-power load off during power up sequence and 2. turning the downstream constant-power load on after the output voltage of the module reaches 48 V steady state After the initial startup, the output of the VIA PFM can be allowed to fall to 30 V during a line dropout at full load. In this case, the circuit should not disable the downstream regulator if the input voltage falls after it is turned on; therefore, some form of hysteresis or latching is needed on the enable signal for the constant power load. The output capacitance of the VIA PFM should also be sized appropriately for a constant power load to prevent collapse of the output voltage of the module during line dropout (see Hold up Capacitance on Page 17). A constant-power load can be turned off after completion of the required hold up time during the power-down sequence or can be allowed to turn off when it reaches its own undervoltage shutdown point. The timing diagram in Figure 25 shows the output voltage of the VIA PFM and the downstream regulator’s enable pin voltage and output voltage of the PRM regulator for the power up and power down sequence. It is recommended to keep the time delay approximately 10 to 20 ms. Special care should be taken when enabling the constant-power load near the auto-ranger threshold, especially with an inductive source upstream of the VIA PFM. A load current spike may cause a large input voltage transient, resulting in a range change which could temporarily reduce the available power (see Adaptive Cell™ Topology below). Adaptive Cell™ Topology The Adaptive Cell topology utilizes magnetically coupled “top” and “bottom” primary cells that are adaptively configured in series or parallel by a configuration controller comprised of an array of switches. A microcontroller monitors operating conditions and defines the configuration of the top and bottom cells through a range control signal. A comparator inside the microcontroller monitors the line voltage and compares it to an internal voltage reference. If the input voltage of the VIA PFM crosses above the positive going cell reconfiguration threshold voltage, the top cell and bottom cell configure in series and the unit operates in “high” range. If the peak of input voltage of the unit falls below the negative-going range threshold voltage for two line cycles, the cell configuration controller configures the top cell and bottom cell in parallel, the unit operates in “low” range. Power processing is held off while transitioning between ranges and the output voltage of the unit may temporarily droop. External output hold up capacitance should be sized to support power delivery to the load during cell reconfiguration. The minimum specified external output capacitance is sufficient to provide adequate ride-through during cell reconfiguration for typical applications. Waveforms showing active cell reconfiguration can be seen in Figure 9. Dielectric Withstand The chassis of the VIA PFM is required to be connected to Protective Earth when installed in the end application and must satisfy the requirements of IEC 60950-1 for Class I products. Both sides of the housing are required to be connected to Protective Earth to satisfy safety and EMI requirements. Protective earthing can be accomplished through dedicated wiring harness (example: ring terminal clamped by mounting screw) or surface contact (example: pressure contact on bare conductive chassis or PCB copper layer with no solder mask). The VIA PFM contains an internal safety approved isolating component (VI ChiP) that provides the Reinforced Insulation from Input to Output. The isolating component is individually tested for Reinforced Insulation from Input to Output at 3000 Vac or 4242 Vdc prior to the final assembly of the VIA™. When the VIA assembly is complete the Reinforced Insulation can only be tested at Basic Insulation values as specified in the electric strength Test Procedure noted in clause 5.2.2 of IEC 60950-1. VIA PFM 48V – 3% VOUT Test Procedure Note from IEC 60950-1 PRM UV Turn on Downstream Regulator “For equipment incorporating both REINFORCED INSULATION and lower grades of insulation, care is taken that the voltage applied to the REINFORCED INSULATION does not overstress BASIC INSULATION or SUPPLEMENTARY INSULATION.” tDELAY Enable Downstream Regulator VOUT tHOLD-UP Figure 25 – PRM Enable Hold off Waveforms VIA PFM™ Rev 1.3 vicorpower.com Page 19 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Summary The final VIA assembly contains basic insulation from input to case, reinforced insulation from input to output, and functional insulation from output to case. The output of the VIA complies with the requirements of SELV circuits so only functional insulation is required from the output (SELV) to case (PE) because the case is required to be connected to protective earth in the final installation. The construction of the VIA can be summarized by describing it as a “Class II” component installed in a “Class I” subassembly. The reinforced insulation from input to output can only be tested at a basic insulation value of 2121 Vdc on the completely assembled VIA product. VI ChiP Isolation Input Output SELV RI Figure 26 – VI Chip before final assembly in the VIA VIA PFM Isolation VI ChiP Input Output VIA Input Circuit SELV VIA Output Circuit RI BI PE FI Figure 27 – PFM VIA after final assembly VIA PFM™ Rev 1.3 vicorpower.com Page 20 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz VIA PFM Chassis Mount Package Mechanical Drawing C .37 9.30 A .152 3.861 THRU TYP B .11 2.90 3 1 OUTPUT INSERT (41817) TO BE REMOVED PRIOR TO USE INPUT INSERT (41816) TO BE REMOVED PRIOR TO USE 2 1.171 29.750 4 86(7<&2/8*25 (48,9)25287387&211(&7,21 86(7<&2/8*25 (48,9)25,1387&211(&7,21 NOTES: 1- RoHS COMPLIANT PER CST-0001 LATEST REVISION. 2- SEE PRODUCT DATA SHEET FOR PIN DESIGNATIONS. PRODUCT 4914 VIA PFM DIM 'A' >@ DIM 'B' >@ DIM 'C' >@ Product outline drawing; Product outline drawings are available in .pdf and .dxf formats. 3D mechanical models are available in .pdf and .step formats. VIA PFM™ Rev 1.3 vicorpower.com Page 21 of 24 07/2015 800 927.9474 1.40 35.54 PFM4914xB6M48D0yzz VIA PFM PCB Mount Package Mechanical Drawing and Recommended Land Pattern DIM 'A' .120±.003 3.048±.076 PLATED THRU .030 [.762] ANNULAR RING (2) PL .15 3.86 (4) PL. DIM 'B' DIM 'F' ±.003 [.076] .112±.003 2.846±.076 .190±.003 4.826±.076 PLATED THRU .030 [.762] ANNULAR RING (2) PL DIM 'B'' ±.003 [.076] D2 B1 .156±.003 3.970±.076 0 1.171±.003 29.750±.076 .947±.003 24.058±.076 .859±.003 21.810±.076 C2 A1 .172±.003 4.369±.076 PLATED THRU .064 [1.626] ANNULAR RING (4) PL. TOP VIEW (COMPONENT SIDE) DIM 'D'' ±.003 [.076] RECOMMENDED HOLE PATTERN (COMPONENT SIDE) DIM 'C' DIM 'L' ±.010 [.254] .366±.010 9.300±.254 SEATING PLANE .080 2.032 (2) PL. .150 3.810 (2) PL. DIM 'L' SHORT .103 [2.607] LONG .182 [4.613] NOTES: 1- RoHS COMPLIANT PER CST-0001 LATEST REVISION. 2- SEE PRODUCT DATA SHEET FOR PIN DESIGNATIONS. DIM 'D' ±.010 [.254] DIM 'F' ±.010 [.254] A1 C2 1.171 29.750 .859±.010 21.810±.254 .947±.010 24.058±.254 .112±.010 2.846±.254 .11 2.90 B1 1.40 35.54 .156 3.970 D2 BOTTOM VEW PRODUCT DIM 'A' DIM 'B' DIM 'C' DIM 'D' DIM 'F' 4914 VIA PFM 2.17 [55.15] 1.757 [44.625] 4.91 [124.77] 4.517 [114.741] 1.999 [50.777] VIA PFM™ Rev 1.3 vicorpower.com Page 22 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Revision History Revision Date 1.0 05/15/15 1.1 05/15 1.2 1.3 Description Page Number(s) Intital release n/a Mechanical Drawing change 20 06/10/15 Revised typical application part numbers SOA Voltage changes Grounding note added Pin name change 2, 3 4 16 18 20 07/16/15 Added Pin Configuration and Description page Added Source Inductor Consideration note Added Safety Approvals Added Source Inductor Consideration section Updated Mechanical drawing 4 6 14 16 21 VIA PFM™ Rev 1.3 vicorpower.com Page 23 of 24 07/2015 800 927.9474 PFM4914xB6M48D0yzz Vicor’s comprehensive line of power solutions includes high density AC-DC and DC-DC modules and accessory components, fully configurable AC-DC and 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. Vicor makes no representations or warranties with respect to the accuracy or completeness of the contents of this publication. Vicor reserves the right to make changes to any products, specifications, and product descriptions at any time without notice. Information published by Vicor has been checked and is believed to be accurate at the time it was printed; however, Vicor assumes no responsibility for inaccuracies. Testing and other quality controls are used to the extent Vicor deems necessary to support Vicor’s product warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. Specifications are subject to change without notice. Vicor’s Standard Terms and Conditions All sales are subject to Vicor’s Standard Terms and Conditions of Sale, which are available on Vicor’s webpage or upon request. Product Warranty In Vicor’s standard terms and conditions of sale, Vicor warrants that its products are free from non-conformity to its Standard Specifications (the “Express Limited Warranty”). This warranty is extended only to the original Buyer for the period expiring two (2) years after the date of shipment and is not transferable. UNLESS OTHERWISE EXPRESSLY STATED IN A WRITTEN SALES AGREEMENT SIGNED BY A DULY AUTHORIZED VICOR SIGNATORY, VICOR DISCLAIMS ALL REPRESENTATIONS, LIABILITIES, AND WARRANTIES OF ANY KIND (WHETHER ARISING BY IMPLICATION OR BY OPERATION OF LAW) WITH RESPECT TO THE PRODUCTS, INCLUDING, WITHOUT LIMITATION, ANY WARRANTIES OR REPRESENTATIONS AS TO MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE, INFRINGEMENT OF ANY PATENT, COPYRIGHT, OR OTHER INTELLECTUAL PROPERTY RIGHT, OR ANY OTHER MATTER. This warranty does not extend to products subjected to misuse, accident, or improper application, maintenance, or storage. Vicor shall not be liable for collateral or consequential damage. Vicor disclaims any and all liability arising out of the application or use of any product or circuit and assumes no liability for applications assistance or buyer product design. Buyers are responsible for their products and applications using Vicor products and components. Prior to using or distributing any products that include Vicor components, buyers should provide adequate design, testing and operating safeguards. Vicor will repair or replace defective products in accordance with its own best judgment. For service under this warranty, the buyer must contact Vicor to obtain a Return Material Authorization (RMA) number and shipping instructions. Products returned without prior authorization will be returned to the buyer. The buyer will pay all charges incurred in returning the product to the factory. Vicor will pay all reshipment charges if the product was defective within the terms of this warranty. Life Support Policy VICOR’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL COUNSEL OF VICOR CORPORATION. As used herein, life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness. Per Vicor Terms and Conditions of Sale, the user of Vicor products and components in life support applications assumes all risks of such use and indemnifies Vicor against all liability and damages. Intellectual Property Notice Vicor and its subsidiaries own Intellectual Property (including issued U.S. and Foreign Patents and pending patent applications) relating to the products described in this data sheet. No license, whether express, implied, or arising by estoppel or otherwise, to any intellectual property rights is granted by this document. Interested parties should contact Vicor's Intellectual Property Department. The products described on this data sheet are protected by the following U.S. Patents Numbers: Patents Pending. Vicor Corporation 25 Frontage Road Andover, MA, USA 01810 Tel: 800-735-6200 Fax: 978-475-6715 email Customer Service: [email protected] Technical Support: [email protected] VIA PFM™ Rev 1.3 vicorpower.com Page 24 of 24 07/2015 800 927.9474