Technical Specification BQ55120QEx50 35-55V 12.0V 50A 2000V dc Quarter-brick Continuous Input Output Max Current Isolation DC-DC Converter The BusQor BQ55120QEx50 bus converter is a nextgeneration, board-mountable, isolated, fixed switching frequency dc/dc converter that uses synchronous rectification to achieve extremely high conversion efficiency. The power dissipated by the converter is so low that a heatsink is not required, which saves cost, weight, height, and application effort. The BusQor series provides an isolated step down voltage from 48V to 12 or 9.6V intermediate bus with no regulation in a standard “quarter-brick” module. BusQor converters are ideal for creating the mid-bus voltage required to drive point-of-load (non-isolated) converters in intermediate bus architectures. Bus High efficiency, 96.8 % at full rated load current at full load Delivers full power with minimal derating - no heatsink required Operating input voltage range: 35-55V dc Fixed frequency switching provides predictable EMI No minimum load requirement Control Features • On/Off control referenced to input side • Inherent current share (by droop method) for high current and parallel applications. Mechanical Features • • • • • Bus Converter BQ55120QEA50NRS-G Operational Features • • • • • ® Safety Features • UL 60950-1:2007 Industry standard size: 1.45” x 2.3” (36.8x58.4mm) Total OF height: 0.467” (11.86mm) Total open frame weight: 1.5 oz (42 g) Total Baseplate height: 0.517" (13.13mm) Total Baseplate weight: 2.7 oz (78 g) • EN60950-1/A11:2009/A1:2010 • CAN/CSA-C22.2 No. 60950-1:2007 • IEC 61000-4-2 Contents Page No. Protection Features • Input under-voltage lockout and over-voltage shutdown protects against abnormal input voltages • Output current limit and short circuit protection (auto recovery) • Output over-voltage protection • Thermal shutdown Product # BQ55120QEx50 Phone 1-888-567-9596 Open Frame Mechanical Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Baseplated Mechanical Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Standards and Qualifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Technical Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Application Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Ordering Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 1 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Open Frame Mechanical 1.450 [ 36.83] .600 [15.24 ] 5 4 .467 ±.020 [ 11.86 ±0.5] OVERALL HEIGHT .056 ±.010 [ 1.42 ±0.25 ] BOTTOMSIDE CLEARANCE 2.300 [ 58.42 ] 2.000 [ 50.8 ] .143 [ 3.63 ] 1 2 3 .425 [ 10.8 ] .110 [ 2.79 ] SEE NOTE 3 .300 [ 7.62 ] .600 [ 15.24 ] NOTES PIN DESIGNATIONS 1) Pins 1-3 are 0.040” (1.02mm) diameter with 0.080” (2.03 mm) diameter standoff shoulders. 2) Pins 4-5 are 0.062” (1.57 mm) diameter with 0.100” (2.54 mm) diameter standoff shoulders. 3) Other pin lengths available. Recommended pin length is 0.03” (0.76mm) greater than the PCB thickness. 4) All Pins: Material - Copper Alloy Finish: Matte Tin over Nickel plate 5) Undimensioned components are shown for visual reference only. 6) All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm) x.xxx +/-0.010 in. (x.xx +/-0.25mm) Pin Name Function 1 Vin(+) Positive input voltage 2 ON/OFF Logic control input to turn converter on/off. 3 Vin(–) Negative input 4 Vout(–) Negative output 5 Vout(+) Positive output 7) Weight: 1.5 oz (42 g) typical 8) Workmanship: Meets or exceeds IPC-A-610C Class II 9) UL/TUV standards require a clearance of 0.04” (1.02mm) around primary areas of the module. 10) The flanged pins are designed to permit surface mount soldering (allowing to avoid the wave soldering process) through the use of the flanged pin-in-paste technique. Product # BQ55120QEx50 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 2 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Baseplated Mechanical Diagram 1.510[38,35] 1.100[27,94] .517±.030 [ 13,13±0,76 ] OVERALL HEIGHT .600 [15,24] .053±.030 [ 1,35±0,76 ] BOTTOMSIDE CLEARANCE 4 5 2.340 [59,44] 1.900 [48,26] 2.000 [50,8] .750 [19,05] 1 2 3 .060 [1,52] .160±.0154,06±0,38[] .455±.01511,56±0,38[] .110 [2,79] SEE NOTE 4 M3 INSERTS (3 PLACES) (SEE NOTES 1&2 .300[7,62] .600[15,24] .850[21,59] NOTES PIN DESIGNATIONS 1) M3 screws used to bolt unit's baseplate to other surfaces such as heatsinks must not exceed 0.10" (2.54mm) depth below the surface of the baseplate. 2) 3) 4) 5) Applied torque per screw should not exceed 6in-lb (0.7nm) Baseplate flatness tolerance is 0.004" (.10mm) TIR for surface Other pin extension lengths available Pins 1-3 are 0.040" (1.02mm) dia. with 0.080" (2.03mm) dia. standoff shoulders 6) Pins 4 and 5 are 0.062" (1.57mm) dia. with 0.100" (2.54mm) dia. standoff shoulders 7) All pins: Material: Copper Alloy Finish: Matte Tin over Nickel plate 8) Undimensioned components are shown for visual reference only 9) Weight: 2.7 oz (78 g) typical 10) All dimensions in inches(mm) Tolerances: x.xxin +/-0.02 (x.xmm +/-0.5mm) x.xxxin +/-0.010 (x.xxmm +/-0.25mm) Product # BQ55120QEx50 Phone 1-888-567-9596 Pin Name Function 1 Vin(+) Positive input voltage 2 ON/OFF Logic control input to turn converter on/off. 3 Vin(–) Negative input 4 Vout(–) Negative output 5 Vout(+) Positive output www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 3 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Technical Specification BQ55120QEx50 Electrical Characteristics Ta = 25 °C, airflow rate = 300 LFM, Vin = 48V dc unless otherwise noted; full operating temperature range is -40 °C to +100 °C ambient temperature with appropriate power derating. Specifications subject to change without notice. Parameter ABSOLUTE MAXIMUM RATINGS Input Voltage Non-Operating Operating Isolation Voltage Input to Output Operating Temperature Storage Temperature Voltage at ON/OFF input pin INPUT CHARACTERISTICS Operating Input Voltage Range Input Under-Voltage Lockout Turn-On Voltage Threshold Turn-Off Voltage Threshold Lockout Voltage Hysteresis Input Over-Voltage Shutdown Turn-On Voltage Threshold Turn-Off Voltage Threshold Maximum Input Current No-Load Input Current Disabled Input Current Input Reflected-Ripple Current Input Terminal-Ripple Current Recommended Input Fuse (see Note 1) Recommended External Input Capacitance Input Filter Component Values (C\L\C) OUTPUT CHARACTERISTICS Output Voltage Set Point Output Voltage Regulation Over Line Over Load Over Temperature Total Output Voltage Range Output Voltage Ripple and Noise Peak-to-Peak RMS Operating Output Current Range Output DC Current-Limit Inception Output DC Current-Limit Shutdown Voltage Back-Drive Current Limit while Disabled Maximum Output Capacitance DYNAMIC CHARACTERISTICS Output Voltage during Load Current Transient Step Change in Output Current (0.1 A/µs) Settling Time Turn-On Transient Turn-On Time (with 5mF output capacitance) Start-Up Inhibit Time Output Voltage Overshoot Product # BQ55120QEx50 Min. Typ. Max. 0 35 48 60 55 V V 2000 100 125 18 V °C °C V 55 V -40 -55 -2 35 48 33.4 31 2.4 47 0.47\11 V V V V V V A mA mA mA mA A µF µH\µF 12.0 V 40\4.75 5.2\500 2\200 %\V %\mV %\mV V 56.9 59.2 8.5 10 600 14.5 110 12.0 20 20 8.300 13.750 75 30 0 Phone 1-888-567-9596 Units Notes & Conditions 125 50 65 10.4 10 5,000 450 100 10 200 0 15 www.synqor.com mV mV A A V mA µF Continuous Continuous RMS through 10µH inductor RMS, full load Fast blow external fuse recommended Typical ESR 0.1-0.2 Ω Internal values No load Vin = 48 V Over sample, line, load, temperature & life 20 MHz bandwidth; see Note 2 Full load Full load Subject to thermal derating Output Voltage 10% Low Vin = 48 V Negative current drawn from output 12.0 Vout at Half Load Resistive Load mV µs 50% to 75% to 50% Iout max To within 1% Vout nom ms ms % Half load, Vout=90% nom. -40 °C to +125 °C; Figure E 5 mF load capacitance Doc.# 005-0005571 Rev. F 10/03/11 Page 4 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Technical Specification BQ55120QEx50 Electrical Characteristics (continued) Ta = 25 °C, airflow rate = 300 LFM, Vin = 48V dc unless otherwise noted; full operating temperature range is -40 °C to +100 °C ambient temperature with appropriate power derating. Specifications subject to change without notice. Parameter Min. Typ. Max. Units Notes & Conditions ISOLATION CHARACTERISTICS Isolation Voltage (dielectric strength) 2000 V See Absolute Maximum Ratings Isolation Resistance 30 MΩ Isolation Capacitance (input to output) 470 pF See Note 3 TEMPERATURE LIMITS FOR POWER DERATING CURVES Semiconductor Junction Temperature 125 °C Package rated to 150 °C Board Temperature 125 °C UL rated max operating temp 130 °C Transformer Core Temperature 140 °C Maximum Baseplate Temperature, Tb 100 °C EFFICIENCY 100% Load 96.8 % 50% Load 97 % FEATURE CHARACTERISTICS Switching Frequency 133 150 165 kHz ON/OFF Control (Option P) Off-State Voltage -1 0.8 V On-State Voltage 2.4 18 V ON/OFF Control (Option N) Off-State Voltage 2.4 18 V On-State Voltage -1 0.8 V ON/OFF Controll (Either Option) Application note Figure B Pull-Up Voltage 5 V Pull-Up Resistance 100 kΩ Over-Temperature Shutdown OTP Trip Point 140 150 °C Average PCB Temperature Over-Temperature Shutdown Restart Hysteresis 10 °C RELIABILITY CHARACTERISTICS Calculated MTBF (Telcordia) TR-NWT-000332 3.7 106 Hrs. 80% load, 300LFM, 40 °C Ta Calculated MTBF (MIL-217) MIL-HDBK-217F 2.9 106 Hrs. 80% load, 300LFM, 40 °C Ta Field Demonstrated MTBF 106 Hrs. See our website for details Note 1: UL’s product certification tests were carried out using 20A fast blow fuse. Fuse interruption characteristics have to be taken into account while designing input traces. User should ensure that Input trace is capable of withstanding fault currents Note 2: For applications requiring reduced output voltage ripple and noise, consult SynQor applications support (e-mail: [email protected]) Note 3: Isolation capacitance can be added external to the module. Product # BQ55120QEx50 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 5 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Technical Specification Standards and Qualifications Parameter Notes & Conditions STANDARDS COMPLIANCE UL 60950-1:2007 Basic insulation EN60950-1/A11:2009/A1:2010 CAN/CSA-C22.2 No. 60950-1:2007 IEC 61000-4-2 ESD test, 8 kV - NP, 15 kV air - NP (Normal Performance) Note: An external input fuse must always be used to meet these safety requirements. Contact SynQor for official safety certificates on new releases or download from the SynQor website. Parameter QUALIFICATION TESTING Life Test Vibration Mechanical Shock Temperature Cycling Power/Thermal Cycling Design Marginality Humidity Solderability Product # BQ55120QEx50 # Units 32 5 5 10 5 5 5 15 pins Phone 1-888-567-9596 Test Conditions 95% rated Vin and load, units at derating point, 1000 hours 10-55 Hz sweep, 0.060" total excursion, 1 min./sweep, 120 sweeps for 3 axis 100g minimum, 2 drops in x, y and z axis -40 °C to 100 °C, unit temp. ramp 15 °C/min., 500 cycles Toperating = min to max, Vin = min to max, full load, 100 cycles Tmin-10 °C to Tmax+10 °C, 5 °C steps, Vin = min to max, 0-105% load 85 °C, 85% RH, 1000 hours, continuous Vin applied except 5 min/day MIL-STD-883, method 2003 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 6 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Technical Figures 100 98.0 95 97.5 97.0 85 Efficiency (%) Efficiency (%) 90 80 75 70 96.5 96.0 35 Vin 25º C 48 Vin 65 55 Vin 60 0 10 20 30 40 Load Current (A) 40º C 95.5 95.0 100 50 Figure 1: Efficiency at nominal output voltage vs. load current for minimum, 55º C 200 Air Flow (LFM) 300 400 Figure 2: Efficiency at nominal output voltage and 60% rated power vs. airflow rate for ambient air temperatures of 25°C, 40°C, and 55°C (nominal input voltage). nominal, and maximum input voltage at 25°C. 13 30 Power Dissipation (W) Power Dissipation (W) 25 20 15 10 35 Vin 5 12 11 10 25º C 40º C 48 Vin 55º C 55 Vin 0 0 10 20 30 40 Load Current (A) 9 100 50 Figure 3: Power dissipation at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25°C. 200 Air Flow (LFM) 300 400 Figure 4: Power dissipation at nominal output voltage and 60% rated power vs. airflow rate for ambient air temperatures of 25°C, 40°C, and 55°C (nominal input voltage). 60 Semiconductor junction temperature is within 1°C of surface temperature 50 Iout (A) 40 30 20 400 300 200 100 10 LFM (2.0 LFM (1.5 LFM (1.0 LFM (0.5 m/s) m/s) m/s) m/s) 0 25 40 55 70 85 Ambient Air Temperature (ºC) Figure 5: Maximum output power-derating curve vs. ambient air temperature for airflow rates of 100 LFM through 400 LFM with air flowing from pin 1 to pin 3 (nominal input voltage). Product # BQ55120QEx50 Phone 1-888-567-9596 Figure 6: Thermal plot of converter at 37.3 A load current (434 W) with 55°C air flowing at the rate of 200 LFM. Air is flowing across the converter from pin 1 to pin 3 (nominal input voltage). www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 7 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Technical Figures 60 50 Iout (A) 40 30 20 400 300 200 100 10 LFM (2.0 LFM (1.5 LFM (1.0 LFM (0.5 m/s) m/s) m/s) m/s) 0 25 40 55 70 85 Semiconductor junction temperature is within 1°C of surface temperature Ambient Air Temperature (ºC) Figure 7: Maximum output power derating curves vs. ambient air temperature for airflow rates of 100 LFM through 400 LFM with air flowing across the converter from output to input (nominal input voltage). Figure 8: Thermal plot of converter at 35.0 A load current (407 W) with 55°C air flowing at the rate of 200 LFM. Air is flowing across the converter from output to input (nominal input voltage). Figure 9: Turn-on transient at 50% load (resistive load) (5 ms/div). Load cap: 5 mF output capacitance. Input voltage pre-applied. Ch 1: Vout (2 V/div), Ch 2: ON/OFF input (2 V/div). Figure 10: Turn-on transient at zero load (5 ms/div). Load cap: 5 mF output capacitance. Ch 1: Vout (2 V/div), Ch 2: ON/OFF input (2 V/div). Figure 11: Output voltage response to step-change in load current (50%-75%50% of Iout(max); dI/dt = 0.1A/µs). Load cap: 15µF tantalum cap and 1µF ceramic cap. Ch 1: Vout (500mV/div), Ch 2: Iout (20A/div). Figure 12: Output voltage response to step-change in load current (50%-75%50% of Iout(max): dI/dt = 1A/µs). Load cap: 15µF, 30 mΩ ESR tantalum cap and 1µF ceramic cap. Ch 1: Vout (500 mV/div), Ch 2: Iout (20A/div). Product # BQ55120QEx50 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 8 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Technical Figures Input Reflected Ripple Current source impedance Input Terminal Ripple Current iS iC Output Voltage Ripple DC-DC Converter VOUT VSOURCE electrolytic capacitor ceramic capacitor tantalum capacitor Figure 13: Test set-up diagram showing measurement points for Input Terminal Ripple Current (Figure 14), Input Reflected Ripple Current (Figure 15) and Output Voltage Ripple (Figure 16). Figure 14: Input Terminal Ripple Current, ic, at full rated output current and nominal input voltage with 10µH source impedance and 47µF electrolytic capacitor (500 mA/div). See Figure 13. Figure 15: Input reflected ripple current, is, through a 10 µH source inductor, using a 47µF electrolytic input capacitor (50 mA/div). See Figure 13. Figure 16: Output voltage ripple at nominal input voltage and rated load current (100 mV/div). Load capacitance: 1µF ceramic capacitor and 15µF tantalum capacitor. Bandwidth: 20 MHz. See Figure 13. 14 Output Voltage (V) 12 10 8 6 4 35 Vin 48 Vin 2 55 Vin 0 0 10 20 30 40 Load Current (A) 50 60 70 Figure 17: Output voltage vs. load current for different input voltages showing typcial current limit curves. Product # BQ55120QEx50 Phone 1-888-567-9596 Figure 18: Load current (50A/div) as a function of time when the converter attempts to turn on into a 1 m-ohm short circuit. Top trace (2ms/div) is an expansion of the on-time portion of the bottom trace. www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 9 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Application Section BASIC OPERATION AND FEATURES CONTROL FEATURES With voltages dropping and currents rising, the economics of an Intermediate Bus Architecture (IBA) are becoming more attractive, especially in systems requiring multiple low voltages. IBA systems separate the role of isolation and voltage scaling from regulation and sensing. The BusQor series bus converter provides isolation and an unregulated voltage step down in one compact module, leaving regulation to simpler, less expensive non-isolated converters. REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2, permits the user to control when the converter is on or off. This input is referenced to the return terminal of the input bus, Vin(-). There are two versions of the converter that differ by the sense of the logic used for the ON/OFF input. In Figure A below, the BusQor module provides the isolation stage of the IBA system. The isolated bus then distributes power to the non-isolated buck regulators to generate the required voltage levels at the points of load. In this case, the bucks are represented with SynQor’s NiQor series of nonisolated DC/DC converters. In many applications requiring multiple low voltage outputs, significant savings can be achieved in board space and overall system costs When designing an IBA system with bus converters, the designer can select from a variety of bus voltages. While there is no universally ideal bus voltage, most designs employ one of the following: 12V, 9V, 7.5V, 5V, or 3.3V. Higher bus voltages can lead to lower efficiency for the buck regulators but are more efficient for the bus converter and provide lower board level distribution current. Lower bus voltages offer the opposite trade offs. In the positive logic version, the ON/OFF input is active high (meaning that a high turns the converter on). In the negative logic version, the ON/OFF signal is active low (meaning that a low turns the converter on). Figure B is a detailed look of the internal ON/OFF circuitry. Vin(+) 5V 5V 124K On/Off 49.9K TTL 100k Vin(-) Figure B: Internal ON/OFF pin circuitry SynQor’s 12 Vout BusQor module acts as a true dc transformer. The output voltage is proportional to the input voltage, with a specified “turns ratio” or voltage ratio, plus minor drop from the internal resistive losses in the module. When used in IBA systems, the output variation of the BusQor must be in accordance with the input voltage range of the non-isolated converters being employed. Typical User Board 2.5 V 48Vdc 35-55V 48Vdc Front End 3.3 V BusQor 12 Vdc Converter 1.8 V 1.5 V 0.9 V NiQor Loads Converters Figure A: Example of Intermediate Bus Architecture using BusQor bus converter and NiQor non-isolated converters Product # BQ55120QEx50 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 10 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Application Section PROTECTION FEATURES Input Under-Voltage Lockout:The converter is designed to turn off when the input voltage is too low, helping avoid an input system instability problem, described in more detail in the application note titled “Input System Instability”. The lockout circuitry is a comparator with DC hysteresis. When the input voltage is rising, it must exceed the typical Turn-On Voltage Threshold value (listed on the specification page) before the converter will turn on. Once the converter is on, the input voltage must fall below the typical Turn-Off Voltage Threshold value before the converter will turn off. Also see Figure E. Output Current Limit: The output of the BusQor module is electronically protected against output overloads. When an overload current greater than the “DC Current-Limit Inception” specification is drawn from the output, the output shuts down to zero volt in a period of 20ms typical (see Figure D). The shutdown period lasts for a typical period of 200ms (Figure D) after which the BusQor tries to power up again. If the overload persists, the output voltage will go through repeated cycles of shutdown and restart with a duty cycle of 10% (On) and 90% (Off) respectively. The BusQor module returns (auto resetting) to normal operation once the overload is removed. The BusQor is designed to survive in this mode indefinitely without damage and without human intervention. Output Current 60A 50A Output Voltage <12V 0V Time 1ms 100A peak Output Current Output Voltage <12V 0V 220ms 20ms Time Figure D: Output Short Circuit and Auto-Resetting protection diagram (not to scale) Output Short Circuit Protection: When the output of the BusQor module is shorted, a peak current of typically 100 A will flow into the short circuit for a period of about 20ms. The output of the BusQor will shutdown to zero for ~ 200mS (Figure D). At the end of the shutdown period the BusQor module tries to power up again. If the short circuit persists, the output voltage will go through repeated cycles of shutdown and restart with a duty cycle of 10% (On) and 90% (Off) respectively. The BusQor module returns (auto resetting) to normal operation once the short circuit is removed. The BusQor is designed to survive in this mode indefinitely without damage and without human intervention. In the Auto resetting mode, also referred to as “Hiccup” mode, the power drawn from the 48V input is about 5 Watts, most of which is dissipated into the external fault. It is important that copper traces and pads from the output circuit be designed to withstand the short term peaks, although the average current into the fault may be as low as 8A typical. See Figure 18 for appropriate waveform. Over-Temperature Shutdown: A temperature sensor on the converter senses the average temperature of the module. The thermal shutdown circuit is designed to turn the converter off when the temperature at the sensed location reaches the Over-Temperature Shutdown value. It will allow the converter to turn on again when the temperature of the sensed location falls by the amount of the Over-Temperature Shutdown Restart Hysteresis value. Figure C: Output Overload protection diagram (not to scale) Product # BQ55120QEx50 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 11 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Application Section APPLICATION CONSIDERATIONS 0.01” Start-Up Inhibit Period: Figure E details the Start-Up Inhibit Period for the BusQor module. At time t0, when Vin is applied with On/Off pin asserted (enabled), the BusQor output begins to build up. Before time t1, when the input voltage is below the UVL threshold, the unit is disabled by the Input Under-Voltage Lockout feature. When the input voltage rises above the UVL threshold, the Input Under-Voltage Lockout is released, and a typical Startup Inhibit Period of 12ms is initiated. The output builds up to 90% of the nominal value of 12V in a period of 15ms typical (50 % load). 0.023” At time t2, when the On/Off pin is de-asserted (disabled), the BusQor output instantly drops to 0V. Fall time from 12V to 0V is dependent on output capacitance and any parasitic trace inductance in the output load circuit. At time t3, when the On/Off pin is re-asserted (enabled), the BusQor module output begins to build up after the inhibit period of 200 ms typical has elapsed. Vin 1.50” Primary Secondary Figure F: Keep Out Areas for BusQor module UVLO Bridging Components: Bridging components like EMI filter capacitors required to be placed as close as possible to the BusQor module for optimum performance must observe the clearance/creepage requirements of 0.04”(40 mils) between pads to maintain compliance to UL standards for the overall power system. On/Off (N logic) OFF ON t0 Vout Bridging Capacitor 0.01” t1 t2 t3 t Note: Referenced keep out widths are adequate to withstand UL’s Basic Insulation Dielectric strength tests for approved PCB materials. Applications requiring Double or Reinforced insulation must double the keep out widths shown in Figure F. Keep out areas shown have standard margins above UL’s minimum requirements. 12V 200ms 12ms Time 215ms Figure E: Power Up/Down Diagram (not to scale) showing Start-Up Inhibit Period Refer to the Control Features section of the data sheet for details on enabling and disabling methods for N and P logic type modules. Component Keep Out Area: Keep out areas for components not referenced to the Primary circuit are shown in shaded areas in Figure F. The keep out areas shown are consistent with UL’s requirements for Basic Insulation of 0.04” (40 mils) for Pollution degree 2. User should consult UL standards for other insulation classes and operating environments. For applications that require mounting parts BELOW the BusQor module, one should be aware of potential high levels of electromagnetic interference, in addition to safety keep out. Users are advised to consult SynQor Applications engineering in such applications. Copper Keep Out Area: Keep out areas shown in Figure F are to be observed for Top layer copper traces and vias. Internal layers buried one or more layers may be exempt, depending on the PCB material grade and thickness. Users are advised to consult UL standards for details. All layers including top and bottom, are subject to the keep out areas shown around Primary pins of BusQor module. Actual keep outs along the surface (Creepage) may vary depending on the PCB material CTI. Users are advised to consult UL standards for details. Product # BQ55120QEx50 Phone 1-888-567-9596 Figure G: Location of Sense Resistor www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 12 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Application Section where: Iload = output load current VRsense(no load) = voltage across the sense resistor with converter at zero load The number 2000 is a “Load Current Scale Factor” for this product, valid only for Vin = 48V. Hence, measurement should be made at this input voltage. + 1 Vin 2 3 2 3 4.0% 3.0% 2.0% 1.0% 0.0% -1.0% -2.0% -3.0% Module 1 Module 2 -4.0% -5.0% 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 Total Load Current (A) Figure I: Current share performance of 2 paralleled modules + BusQor module (N logic option) 5 Current Sharing: BusQor modules are designed to operate in parallel without the use of any external current share circuitry. A typical circuit for paralleling two BusQor modules is shown in Figure H. An output capacitor 12Vout is recommended across each module and located close to the converter 50A for optimum filtering and noise control performance. Dedicated input inductors are recommended but are considered optional. Input capacitors must be located close to the converter module. PCB layout in the input circuit should be such that high frequency ripple currents of each module is — restricted to a loop formed by the input capacitors and the input terminals of the BusQor module. See Figure J for details on PCB layout. Contact SynQor application engineering for further assistance on PCB trace design. 4 The current share performance of two paralleled modules is illustrated in the graph in Figure I. In this graph the percent deviation from ideal sharing (50%) is plotted for each module versus the total output load current at 48Vin. 5 4 — 1 5.0% Deviation from 50/50 Sharing (%) Output Load Current Calculation: The BusQor series allows the converter output load to be measured without adding a current loop or external shunt resistor to the designer’s PCB board under test. On the top side of the BusQor converter is a current sense resistor as shown in Figure G. The output load current is proportional to the voltage drop across this sense resistor. This calculation is detailed below. A current sense resistor referenced to the primary input is used in the equation below to calculate the output load current. Iload = (VRsense(load) - VRsense(no load) ) x 2000 BusQor module (N logic option) Figure H: BusQor Output Paralleling for increased current output The voltage drop across the sense resistor is about 25 mV at full load of 50 A. Therefore, proper measuring techniques must be used to ensure accuracy. A calibrated DMM set to 300mV is acceptable. Since this measurement is done on the Primary area of the converter, a slight non-linearity may be observed over the load current range. Measurements should be made at 48 V input voltage. Using the Scale Factor referenced above, the error may be on the order of 4%. For more detailed information consult the application note on SynQor’s website titled “Output Load Current Calculations”. BusQor module 48Vin CM EMI filter (Not shown in Figure H) Bulk Cap BusQor module Input LC filters Figure J: Recommended PCB layout for input circuit Product # BQ55120QEx50 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 13 Input:35-55V Output:12.0V Current:50A Part No.:BQ55120QEx50 Ordering Section PART NUMBERING SYSTEM ORDERING INFORMATION The part numbering system for SynQor’s dc-dc converters follows the format shown in the example below. The tables below show the valid model numbers and ordering options for converters in this product family. When ordering SynQor converters, please ensure that you use the complete 15 character part number consisting of the 12 character base part number and the additional characters for options. Add “-G” to the model number for 6/6 RoHS compliance. BQ 5 5 1 2 0Q E A5 0 N R S -G 6/6 RoHS Options (see Ordering Information) Output Current Model Number BQ55120QEw50xyz-G Input Voltage 35-55V Output Voltage 12.0V Max Output Current 50A Thermal Design Performance Level The following options must be included in place of the w x y z spaces in the model numbers listed above. Package Size Output Voltage Options Description: w x y z Input Voltage Product Family The first 12 characters comprise the base part number and the last 3 characters indicate available options. The “-G” suffix indicates 6/6 RoHS compliance. Application Notes A variety of application notes and technical white papers can be downloaded in pdf format from our website. RoHS Compliance: The EU led RoHS (Restriction of Hazardous Substances) Directive bans the use of Lead, Cadmium, Hexavalent Chromium, Mercury, Polybrominated Biphenyls (PBB), and Polybrominated Diphenyl Ether (PBDE) in Electrical and Electronic Equipment. This SynQor product is 6/6 RoHS compliant. For more information please refer to SynQor’s RoHS addendum available at our RoHS Compliance / Lead Free Initiative web page or e-mail us at [email protected]. Thermal Design Enable Logic Pin Style Feature Set A - Open Frame B - Baseplated N - Negative P - Positive K - 0.110" N - 0.145" R - 0.180" Y - 0.250" S - Standard Not all combinations make valid part numbers, please contact SynQor for availability. See the Product Summary web page for more options. PATENTS SynQor holds the following U.S. patents, one or more of which apply to each product listed in this document. Additional patent applications may be pending or filed in the future. 5,999,417 6,222,742 6,545,890 6,577,109 6,594,159 6,731,520 6,894,468 6,896,526 6,927,987 7,050,309 7,072,190 7,085,146 7,119,524 7,269,034 7,272,021 7,272,023 7,558,083 7,564,702 7,765,687 7,787,261 8,023,290 Contact SynQor for further information: Phone: Toll Free: Fax: E-mail: Web: Address: Product # BQ55120QEx50 978-849-0600 888-567-9596 978-849-0602 [email protected] www.synqor.com 155 Swanson Road Boxborough, MA 01719 USA Phone 1-888-567-9596 Warranty SynQor offers a three (3) year limited warranty. Complete warranty information is listed on our website or is available upon request from SynQor. Information furnished by SynQor is believed to be accurate and reliable. However, no responsibility is assumed by SynQor for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SynQor. www.synqor.com Doc.# 005-0005571 Rev. F 10/03/11 Page 14