Technical S pecification BQ55120ETx20 35-55V 12V 240Watt 2250Vdc Eighth-brick Input Output Power Isolation DC Bus Conver ter The BusQor(R) BQ55120ETx20 bus converter is a next-generation, 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 Bus Conver ter saves cost, weight, height, and application effort. The BusQor series provides an isolated step down voltage from 35-55V to a 12V intermediate bus with no regulation in a standard "eighth-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. RoHS Compliant (see page 13 ). Operational Features * Ultra-high efficiency, >95.5% at full rated load current * Delivers up to 20 amps of output current (240W) with minimal derating - no heatsink required * Input voltage range: 35V - 55V provides 12V bus for distributed power architectures * Fixed frequency switching provides predictable EMI performance Mechanical Features * Industry standard eighth-brick bus converter pin-out * Industry standard size: 0.90" x 2.3" (22.9x58.4mm) * Total height only 0.484" (12.29mm), permits better airflow and smaller card pitch * Total weight: 0.7 oz. (20 grams) * Flanged pins designed to permit surface mount soldering (avoid wave solder) using FPiP technique Contr ol Features BQ55120ETA20 Module Pr otection Features * Input under-voltage lockout and over-voltage shutdown protects against abnormal input voltages * Output current limit and short circuit protection * Thermal shutdown Safety Features * 2250V, 30 MW input-to-output isolation * UL/cUL 60950-1 recognized (US & Canada), basic insulation rating * TUV certified to EN60950-1 * Meets 72/23/EEC and 93/68/EEC directives * Meets UL94V-0 flammability requirements * On/Off control referenced to input side (positive and negative logic options available) Product # BQ55120ETx20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 1 Input: Output: Current: Package: Technical Specification MECHANICAL DIAGRAM 35-55 V 12 V 20 A (240W) Eighth-brick 2.30 (58.4) (open frame) 2.00 (50.8) 0.14 (3.6) 5 1 Top View 0.90 0.15 (22.9) 2 (3.8) 3 0.600 4 (15.24) 0.300 (7.62) 0.082 +0.017 (2.08 +0.43) Side View Bottom side Clearance See Note 9 0.145 Lowest Component Flanged Pin See Note 10 Load Board Overall height 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 and 5 are 0.062" (1.57 mm) diameter with 0.100" (2.54 mm) diameter standoff shoulders. 3) Other pin extension 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) 7) Weight: 0.7 oz. (20 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. Refer to section on Keep Out Areas under Application Considerations for details. 10) The flanged pins are designed to permit surface mount soldering (avoiding the wave soldering process) through the use of the flanged pin-in-paste technique. Product # BQ55120ETx20 0.463 +0.018 (11.76 +0.46) (3.68) See Note 3 Phone 1-888-567-9596 Pin No. Name Function 1 Vin(+) Input Positive (35V - 55V) 2 ON/OFF Logic control input to turn converter on and off. 3 Vin(-) Input Negative 4 Vout(-) Output Negative 5 Vout(+) Output Positive www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 2 Input: Output: Current: Package: Technical Specification 35-55 V 12 V 20 A (240W) Eighth-brick MECHANICAL DIAGRAM (encased) 0.99 (25) 0.600 (15.24) 0.496 0.025 (12.6 0.63) Overall height 5 4 Flanged Pin See Note 10 2.39 (60.6) 2.00 Top View (50.8) Side View 0.18 (4.6) 0.145 1 2 (3.68) See Note 3 3 0.19 (4.9) 0.300 (7.62) 0.600 (15.24) NOTES (0.25 0.25) Botom side clearance See Note 9 PIN DESIGNATIONS 1) Pins 1-3 are 0.040" (1.02mm) diameter with 0.080" (2.03 mm) diameter standoff shoulders. 2) Pins 4 and 5 are 0.062" (1.57 mm) diameter with 0.100" (2.54 mm) diameter standoff shoulders. 3) Other pin extension 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) 7) Weight: TBD oz. (TBD g) typical 8) Workmanship: Meets or exceeds IPC-A-610C Class II 9) 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. 10) Baseplate tolerance is 0.004" (0.10mm) TIR for surface. Product # BQ55120ETx20 0.010 0.010 Phone 1-888-567-9596 www.synqor.com See previous page Doc.# 005-2BE553C Rev. D 09/26/11 Page 3 Input: Output: Current: Package: Technical Specification 35-55 V 12 V 20 A (240W) Eighth-brick BQ55120ETx20 ELECTRICAL CHARACTERISTICS TA=25C, airflow rate=300 LFM, Vin=48Vdc unless otherwise noted; full operating temperature range is -40C to +100C ambient temperature with appropriate power derating. Specifications subject to change without notice. Parameter Min. Typ. Max. Units 60 56 2250 100 125 18 V V V C C V 55 V Notes & Conditions ABSOLUTE MAXIMUM RATINGS Input Voltage Non-Operating Operating Isolation Voltage (input to output) Operating Temperature Storage Temperature Voltage at ON/OFF input pin -40 -55 -2 Continuous Continuous Basic insulation, Pollution Degree 2 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-Off Voltage Threshold Turn-On Voltage Threshold Maximum Input Current No-Load Input Current Disabled Input Current Inrush Current Transient Rating Input Reflected Ripple Current Input Terminal Ripple Current Recommended Input Fuse Input Filter Component Values (L\C) Recommended External Input Capacitance 35 48 32.0 30.5 1.5 V V V 59.0 58.0 1.5\2.0 47 V V A A mA A 2s mA mA A H\F F 12.00 V +20 \ 2.4 +4.1 \ 500 +1.7 \ 200 %\V %\mV %\mV V 7 10 50 5.5 0.1 15 0.1 100 12 100% Load, 35Vin RMS through 10H inductor; Figures 12 & 14 RMS, full load; Figures 12 & 13 Fast blow external fuse recommended Internal values Typical ESR 0.1-0.2W, see Figure 12 OUTPUT CHARACTERISTICS Output Voltage Set Point Output Voltage Regulation Over Line Over Load Over Temperature Total Output Voltage Range Output Voltage Ripple and Noise1 Peak-to-Peak RMS Operating Output Current Range Output DC Current-Limit Inception Output DC Current-Limit Shutdown Voltage Current Share Accuracy (2 units paralleled) Back-Drive Current Limit while Disabled Maximum Output Capacitance 8.0 13.8 100 20 0 150 40 20 27 Vin / 8 +10 10 3,000 mV mV A A V % mA F 48Vin, no load Figure 4 Figure 4 Figure 4 Over sample, line, load, temperature & life 20MHz bandwidth; Figures 12 & 15 Full Load, see Figures 12 & 15 Full Load, see Figures 12 & 15 Subject to thermal derating; Figures 5 - 8 Output Voltage 10% Low; Figure 16 % of rated output current Negative current drawn from output 12Vout at 20A Resistive Load DYNAMIC CHARACTERISTICS Output Voltage during Load Current Transient For a Step Change in Output Current (0.1A/s) Settling Time Turn-On Transient Turn-On Time Start-Up Inhibit Time Output Voltage Overshoot 200 200 mV s 50% to 75% to 50% Iout max; Figure 11 To within 1% Vout nom 9 3 0 ms ms % Full load, Vout=90% nom.; Figures 9 & 10 -40C to +125C 2,500 F load capacitance, Iout = 0A 95.5 96.0 % % Figures 1 - 3 Figures 1 - 3 C C C Package rated to 150C UL rated max operating temp 130C See Figures 5 - 8 for derating curves EFFICIENCY 100% Load 50% Load TEMPERATURE LIMITS FOR POWER DERATING CURVES Semiconductor Junction Temperature Board Temperature Transformer Temperature 125 125 125 ISOLATION CHARACTERISTICS Isolation Voltage (dielectric strength) Isolation Resistance 2250 30 V MW Note 1: For applications requiring reduced output voltage ripple and noise, consult SynQor applications support (e-mail: support@synqor.com). Product # BQ55120ETx20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 4 Input: Output: Current: Package: Technical Specification 35-55 V 12 V 20 A (240W) Eighth-brick ELECTRICAL CHARACTERISTICS (Continued) Parameter Min. Typ. Max. Units 165 190 215 kHz -1.0 2.4 0.8 18 V V 2.4 -1.0 18 0.8 V V Notes & Conditions FEATURE CHARACTERISTICS Switching Frequency ON/OFF Control (Option P) Off-State Voltage On-State Voltage ON/OFF Control (Option N) Off-State Voltage On-State Voltage ON/OFF Control (Either Option) Pull-Up Voltage Pull-Up Resistance Over-Temperature Shutdown Over-Temperature Shutdown Restart Hysteresis Load Current Scale Factor Figures A & B 10 30 140 150 10 667 Average PCB Temperature See App Note: Output Load Current Calc. RELIABILITY CHARACTERISTICS Calculated MTBF (Telcordia) Calculated MTBF (MIL-217) Field Demonstrated MTBF V kW C C 106 Hrs. TR-NWT-000332; 80% load,300LFM, 40oC Ta 106 Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40oC Ta 106 Hrs. See our website for details 2.36 1.79 STANDARDS COMPLIANCE Parameter P Notes STANDARDS COMPLIANCE UL/cUL 60950-1 EN60950-1 72/23/EEC 93/68/EEC Needle Flame Test (IEC 695-2-2) IEC 61000-4-2 GR-1089-CORE File # E194341, Basic insulation & pollution degree 2 Certified by TUV Test on entire assembly; board & plastic components UL94V-0 compliant ESD test, 8kV - NP, 15kV air - NP (Normal Performance) Section 7 - electrical safety, Section 9 - bonding/grounding * 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. QUALIFICATION TESTING Parameter P QUALIFICATION TESTING Life Test Vibration Mechanical Shock Temperature Cycling Power/Thermal Cycling Design Marginality Humidity Solderability # Units 32 5 5 10 5 5 5 3 Test Conditions 95% rated Vin and load, units at derating point, 1000 hours 10-55Hz sweep, 0.060" total excursion,1 min./sweep, 120 sweeps for 3 axis 100g minimum, 2 drops in x and y axis, 1 drop in z axis -40C to 100C, unit temp. ramp 15C/min., 500 cycles Toperating = min to max, Vin = min to max, full load, 100 cycles Tmin-10C to Tmax+10C, 5C steps, Vin = min to max, 0-105% load 85C, 85% RH, 1000 hours, 2 minutes on and 6 hours off MIL-STD-883, method 2003 * Extensive characterization testing of all SynQor products and manufacturing processes is performed to ensure that we supply robust, reliable product. Contact factory for official product family qualification document. OPTIONS PATENTS SynQor provides various options for Pin Length and Feature Set for this family of Power Interface Modules. Please consult the last page for information on available options. SynQor is protected under various patents. Please consult the last page for further information. Product # BQ55120ETx20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 5 35-55 V 12 V 20 A (240W) Eighth-brick Input: Output: Current: Package: Technical Specification 11 100 10 9 Power Dissipation (W) Efficiency (%) 95 90 85 80 35 Vin 75 8 7 6 5 4 3 35 Vin 48 Vin 2 48 Vin 55 Vin 1 55 Vin 70 0 0 4 8 12 16 0 20 4 8 Load Current (A) 12 16 20 Load Current (A) Figure 1: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25C. Figure 2: Power dissipation at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25C. 14 97 13 12 Output Voltage (V) Efficiency (%) 96 95 94 11 10 9 8 25 C 35V 40 C 48V 7 55 C 55V 93 6 100 200 300 400 0 Air Flow (LFM) 2 4 6 8 10 12 14 16 Load Current (A) Figure 3: Efficiency at nominal output voltage and 60% rated power vs. airflow rate for ambient air temperatures of 25C, 40C, and 55C (nominal input voltage). Figure 4: Output voltage regulation vs. load current for minimum, nominal, and maximum input voltage at 25C. 20 Iout (A) 16 12 8 400 LFM (2.0 m/s) 300 LFM (1.5 m/s) 4 200 LFM (1.0 m/s) 100 LFM (0.5 m/s) Semiconductor junction temperature is within 1C of surface temperature 0 0 25 40 55 70 85 Ambient Air Temperature (C) Figure 5: Maximum output power derating curves vs. ambient air temperature for airflow rates of 100 LFM through 400 LFM with air flowing from pin 3 to pin 1 (nominal input voltage). Product # BQ55120ETx20 Phone 1-888-567-9596 Figure 6: Thermal plot of converter at 20 amp load current (240W) with 55C air flowing at the rate of 200 LFM. Air is flowing across the converter from pin 3 to pin 1 (nominal input voltage). www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 6 Input: Output: Current: Package: Technical Specification 35-55 V 12 V 20 A (240W) Eighth-brick 20 Semiconductor junction temperature is within 1C of surface temperature Iout (A) 16 12 8 400 LFM (2.0 m/s) 300 LFM (1.5 m/s) 4 200 LFM (1.0 m/s) 100 LFM (0.5 m/s) 0 0 25 40 55 70 85 Ambient Air Temperature (C) Figure 7: Maximum output power derating curves vs. ambient air temperature for airflow rates of 100 LFM through 400 LFM with air flowing from output to input (nominal input voltage). Figure 8: Thermal plot of converter at 20 amp load current (240W) with 55C 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 half load (resistive load) and 3mF output capacitance (2.0ms/div). Input voltage pre-applied. Channel 1: Vout (2V/div). Channel 2: ON/OFF input (2V/div). Figure 10: Turn-on transient at zero load and 3mF output capacitance (2.0ms/div). Input voltage pre-applied. Channel 1: Vout (2V/div). Channel 2: ON/OFF input (2V/div). DC/DC Converter Figure 11: Output voltage response to step-change in load current (50%-75%50% of Iout(max); dI/dt = 0.1A/ s). Load cap: 15 F, 100 mW ESR tantalum cap and 1 F ceramic cap. Top trace: Vout (200mV/div), Bottom trace: Iout (5A/div). Product # BQ55120ETx20 Phone 1-888-567-9596 Figure 12: Test set-up diagram showing measurement points for Input Terminal Ripple Current (Figure 13), Input Reflected Ripple Current (Figure 14) and Output Voltage Ripple (Figure 15). www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 7 Input: Output: Current: Package: Technical Specification Figure 13: Input Terminal Ripple Current, ic, at full rated output current and nominal input voltage with 10 H source impedance and 47 F electrolytic capacitor (50 mA [200mV]/div). See Figure 12. 35-55 V 12 V 20 A (240W) Eighth-brick Figure 14: Input reflected ripple current, is, through a 10 H source inductor at nominal input voltage and rated load current (5mA [10mV]/div). See Figure 12. 14 Output Voltage (V) 12 10 8 6 4 35V 48V 2 55V 0 0 5 10 15 20 25 30 Load Current (A) Figure 15: Output voltage ripple at nominal input voltage and rated load current (50 mV/div). Load capacitance: 1 F ceramic capacitor and 15 F tantalum capacitor. Bandwidth: 20 MHz. See Figure 12. Figure 16: Output voltage vs. load current showing typical current limit curves and converter shutdown points. 1 35 Vin Output Impedance (ohms) 48 Vin 55 Vin 0.1 0.01 10 100 1,000 10,000 100,000 Hz Figure 17: Load current (10A/div) as a function of time when the converter attempts to turn on into a 1 mW short circuit. Top trace (5.0ms/div) is an expansion of the on-time portion of the bottom trace. Product # BQ55120ETx20 Phone 1-888-567-9596 Figure 18: Magnitude of incremental output impedance (Zout = vout/iout) for minimum, nominal, and maximum input voltage at full rated power. www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 8 Input: Output: Current: Package: 10 10 0 0 Reverse Transmission (dB) Forward Transmission (dB) Technical Specification -10 -20 35 Vin -30 48 Vin 35-55 V 12 V 20 A (240W) Eighth-brick -10 -20 35 Vin -30 48 Vin 55 Vin 55 Vin -40 -40 10 100 1,000 10,000 100,000 10 Hz 100 1,000 10,000 100,000 Hz Figure 19: Magnitude of incremental forward transmission (FT = vout/vin) for minimum, nominal, and maximum input voltage at full rated power. Figure 20: Magnitude of incremental reverse transmission (RT = iin/iout) for minimum, nominal, and maximum input voltage at full rated power. 10000 Input Impedance (ohms) 1000 100 10 35 Vin 1 48 Vin 55 Vin 0.1 10 100 1,000 10,000 100,000 Hz Figure 21: Magnitude of incremental input impedance (Zin = vin/iin) for minimum, nominal, and maximum input voltage at full rated power. Product # BQ55120ETx20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 9 Input: Output: Current: Package: Technical Specification BASIC OPERATION AND 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. 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 non-isolated 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. 35-55 V 12 V 20 A (240W) Eighth-brick the output variation of the BusQor must be in accordance with the input voltage range of the non-isolated converters being employed. The BusQor architecture is very scalable, allowing for multiple bus converters can be connected directly in parallel to allow current sharing for higher power applications. CONTROL FEATURES 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 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. Positive logic enabled modules have N-channel FET populated. Negative logic enabled modules have P-channel FET populated. Vin+ 5V 124k SynQor's 12Vout 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, On/Off 49.9k TTL 100k 3.3 V Vin2.5 V 48Vdc 35-55V BusQor Figure B: Internal ON/OFF pin circuitry 12Vdc Converter 1.8 V PROTECTION FEATURES 1.5 V 0.9 V Typical User Board NiQor Loads Converters 48Vdc Front End Figure A: Example of Intermediate Bus Architecture using BusQor bus converter and NiQor non-isolated converters Product # BQ55120ETx20 Phone 1-888-567-9596 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. www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 10 Input: Output: Current: Package: Technical Specification 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 volts in a period of 10mS typical (see Figure C). The shutdown period lasts for a typical period of 250mS (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 4% (On) and 96% (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 35-55 V 12 V 20 A (240W) Eighth-brick the short circuit persists, the output voltage will go through repeated cycles of shutdown and restart with a duty cycle of 4% (On) and 96% (Off) respectively. The BusQor module returns (auto recovery) 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 recovery 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 2A typical. See Figure 17 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 OverTemperature 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. 27A 20A Output Voltage 12V APPLICATION CONSIDERATIONS 0V 10ms Time Figure C: Output Overload protection diagram (not to scale) Output Short Circuit Protection: When the output of the BusQor module is shorted, a peak current of typically 42A will flow into the short circuit for a period of about 10mS. The output of the BusQor will shutdown to zero volts for the same period (Figure E). The shutdown period lasts for a period of 250mS, at the end of which the BusQor module tries to power up again. If Output Current 42A peak Output Voltage 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 3mS is initiated. The output builds up to 90% or higher of the nominal voltage and stabilizes at the nominal value of 12.0V. The rise time from 0V to 90% is 1.5mS typical. At time t2, when the On/Off pin is de-asserted (disabled), the BusQor output instantly drops to 0V. Fall time from 12.0V 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 3mS typical. 12V Refer to the Control Features section of the data sheet for details on enabling and disabling methods for N and P logic type modules. 0V Time 250ms 10ms Figure D: Output Short Circuit and Auto-Resetting protection diagram (not to scale) Product # BQ55120ETx20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 11 Input: Output: Current: Package: Technical Specification 35-55 V 12 V 20 A (240W) Eighth-brick 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. Vin UVLO 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. On/Off (N logic) OFF ON t0 t1 t2 t3 t Vout 12V 3ms 3ms Time 4.5ms Figure E: Power Up/Down Diagram (not to scale) showing Start-Up Inhibit Period. Keep Out Areas: 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. 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. 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. 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 667 where: Iload = output load current VRsense(load) = voltage across the sense resistor with converter under load VRsense(no load) = voltage across the sense resistor with 0.010" converter at zero load Figure F: Keep Out Areas for BusQor module 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. Product # BQ55120ETx20 Phone 1-888-567-9596 The number 667 is a "Load Current Scale Factor" for this product, valid only for Vin = 48V. Hence, measurement should be made at this input voltage. The voltage drop across the sense resistor is about 30mV at a full load of 20A. Therefore, proper measuring techniques must www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 12 Input: Output: Current: Package: Technical Specification The current share performance of two paralleled modules is illustrated in the graph in Figure J. In this graph the percent deviation from ideal sharing (50%) is plotted for each module versus the total output load current at 48Vin. 5.0% 4.0% Deviation from 50/50 Sharing (%) 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. 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 web site titled "Output Load Current Calculations". 35-55 V 12 V 20 A (240W) Eighth-brick Current Sharing: BusQor modules are designed to operate in 3.0% 2.0% 1.0% 0.0% -1.0% -2.0% -3.0% Module 1 -4.0% Module 2 -5.0% 5 10 15 20 25 30 35 40 Total Load Current (A) Figure G: Location of Sense Resistors Figure J: Current share performance of 2 paralleled modules 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 is recommended across each module and located close to the converter 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 K for details on PCB layout. Contact SynQor application engineering for further assistance on PCB trace design. 5 1 BusQor module (N logic option) Vin 2 3 4 1 5 48Vin BusQor module CM EMI filter Bulk Cap BusQor module (Not shown in Figure H) Input LC filters Figure K: Recommended PCB layout for input circuit RoHS Compliance: The EU led RoHS (Restriction of Hazardous Substances) Directive bans the use of Lead, Cadmium, Hexavalent Chromium, Mercury, Polybrominated Biphenyls 12Vout (PBB), and Polybrominated Diphenyl Ether (PBDE) in Electrical 40A and Electronic Equipment. This SynQor product is available as 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 rohs@synqor.com. BusQor module (N logic option) 2 3 4 Figure H: BusQor Output Paralleling for increased current output. Product # BQ55120ETx20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE553C Rev. D 09/26/11 Page 13 Input: Output: Current: Package: Technical Specification 35-55 V 12 V 20 A (240W) Eighth-brick PART NUMBERING SYSTEM ORDERING INFORMATION The part numbering system for SynQor's BusQor DC bus 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 3 characters for options. A "-G" suffix indicates the product is 6/6 RoHS compliant. BQ 55 120 E T A 20 N N S - G 6/6 RoHS Options (see Ordering Information) Output Current Thermal Design Performance Level Package Size Model Number Input Voltage BQ55120ETw 20xyz -G 35 - 55 V Output Max Output Voltage Current 12 V 20 A The following option choices must be included in place of the x y z spaces in the model numbers listed above. Output Voltage Input Voltage Product Family Options Description: w x y z Thermal Design Pin Feature Length Set K - 0.110" A - Open Frame P - Positive N - 0.145" S - Standard C - Encased N - Negative R - 0.180" Y - 0.250" * Consult the factory before ordering the P logic option The first 12 characters comprise the base part number and the last 3 characters indicate available options. Although there are no default values for enable logic and pin length, the most common options are negative logic and 0.145" pins. These part numbers are more likely to be readily available in stock for evaluation and prototype quantities. A "-G" suffix indicates the product is 6/6 RoHS compliant. Enable Logic * Application Notes A variety of application notes and technical white papers can be downloaded in pdf format from our website. 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 # BQ55120ETx20 978-849-0600 888-567-9596 978-849-0602 power@synqor.com 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.# 005-2BE553C Rev. D 09/26/11 Page 14