Technical Specification BQ55120ETL16 35-55 V 12 V 16 A 192 W 2000 Vdc Eighth-brick Input Output Current Power Isolation DC-DC Converter ® The BusQor® BQ55120ETL16 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 35-55 V to 12 V 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. BQ55120ETL16 Model Operational Features • • • • • Mechanical Features High efficiency, 95% at full rated load current Delivers 16 A full power with minimal derating - no heatsink required Operating input voltage range: 35-55 V Fixed frequency switching provides predictable EMI No minimum load requirement • Industry standard eighth-brick bus converter pin-out • Size: 0.90” x 2.3” (22.9x58.4mm) x 0.320” (8.13 mm) • Total weight: 0.81 oz (23 g) Protection Features • Input under-voltage lockout and over-voltage shutdown protects against abnormal input voltages • Output current limit and short circuit protection (auto recovery) • Thermal shutdown Control Features • On/Off control referenced to input side (positive and negative logic options are available) • Inherent current share (by droop method) for high current and parallel applications. Contents Page No. Safety Features • UL 60950-1:2007/R:2011-12 • EN 60950-1:2006/A2:2013 • CAN/CSA C22.2 No. 60950-1:2007/A1:2011 Product # BQ55120ETL16 Phone 1-888-567-9596 Open Frame Mechanical Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Compliance & Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Technical Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Applications Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 www.synqor.com Doc.# 005-2BE552B Rev. E 03/21/16 Page 1 Open Frame Mechanical Diagram Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick NOTES PIN DESIGNATIONS 1)PINS 1-3 ARE 0.040” (1.02 mm) DIA. WITH 0.080” (2.03 mm) DIA. STANDOFF SHOULDERS 2)PINS 4 & 5 ARE 0.062” (1.57 mm) DIA. WITH 0.100” (2.54 mm) DIA. STANDOFF SHOULDERS 3)MAX SCREW DEPTH MUST NOT EXCEED .085” BELOW THE SURFACE OF THE BASE PLATE 4)OTHER PIN EXTENSION LENGTHS AVAILABLE 5)ALL PINS: MATERIAL: COPPER ALLOY FINISH: MATTE TIN OVER NICKEL PLATE 6)UNDIMENSIONED COMPONENTS ARE SHOWN FOR VISUAL REFERENCE ONLY 7)ALL DIMENSIONS IN INCHES(mm) TOLERANCES: X.XXIN +/-0.02 (X.X mm +/-0.5 mm) X.XXX IN +/-0.010 (X.XX mm +/-0.25 mm) 8)WEIGHT: 0.81 oz (23 g) 9)WORKMANSHIP: MEETS OR EXCEEDS IPC-A-610C CLASS II 10)UL/TUV STANDARDS REQUIRE A CLEARANCE OF 0.04” (1.02 mm) AROUND PRIMARY AREAS OF THE MODULE. Product # BQ55120ETL16 Phone 1-888-567-9596 Pin Name 1 Vin(+) 2 ON/OFF 3 Vin(-) 4 Vout(-) 5 Vout(+) www.synqor.com Function Positive Input Voltage TTL input to turn converter on and off, referenced to Vin (-) with internal pull up Negative input voltage Negative output voltage Positive output voltage Doc.#005-2BE552B Rev. E 03/21/16 Page 2 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Technical Specification BQ55120ETL16 Electrical Characteristics Ta = 25 °C, airflow rate = 300 LFM, Vin = 48 V 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. 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 Inrush Current Transient Rating Input Reflected Ripple Current Input Terminal Ripple Current Recommended Input Fuse (see Note 1) Recommended External Input Capacitance Input Filter Component Values (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 Current Share Accuracy (2 units paralleled) Back-Drive Current Limit while Disabled Maximum Output Capacitance EFFICIENCY 100% Load 50% Load Product # BQ55120ETL16 Typ. -1 -40 -45 -2 35 48 Max. 60 56 2000 100 125 18 V V V °C °C V 55 V 32.0 30.5 1.5 58.0 59.0 7.0 5 50 4.7 0.1 15.0 0.1 100 12 V V V V V V A mA mA A2s mA mA A µF 47 1.5\2.0 µH\µF 12.00 V + 20 \ 2.4 + 4.1 \ 500 + 1.7 \ 200 13.8 %\V %\mV %\mV V 150 40 16 mV mV A 3,000 A V % mA µF 8.0 Phone 1-888-567-9596 Units Notes & Conditions 100 20 0 25 Vin / 8 + 10 10 95 95 www.synqor.com % % Continuous Continuous Basic Insulation, Pollution Degree 2 100% Load, 35 Vin RMS through 10 µH inductor; Figures 12 & 14 RMS, full load; Figures 12 & 13 Fast blow external fuse recommended Typical ESR 0.1-0.2 Ω; see Figure 12 Internal values 48 Vin, no load Figure 4 Figure 4 Figure 4 Over sample, line, load, temperature & life 20 MHz bandwidth; see Note 2; 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 Negative current drawn from output 12 Vout at 16 A Resistive Load Figures 1 & 3 Figures 1 & 3 Doc.# 005-2BE552B Rev. E 03/21/16 Page 3 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Technical Specification BQ55120ETL16 Electrical Characteristics (continued) Ta = 25 °C, airflow rate = 300 LFM, Vin = 48 V 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. 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 Start-Up Inhibit Time Output Voltage Overshoot ISOLATION CHARACTERISTICS Typ. Max. Units Notes & Conditions 200 200 mV µs 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 -40 °C to +125 °C 2.5 mF load capacitance, Iout = 0 A Isolation Voltage (dielectric strength) 2000 V See Absolute Maximum Ratings Isolation Resistance 30 MΩ Isolation Capacitance n/a See Note 3 TEMPERATURE LIMITS FOR POWER Semiconductor Junction Temperature 125 °C Package rated to 150 °C Board Temperature 125 °C UL rated max operating temp 130 °C Transformer Core Temperature 125 °C See Figures 5 - 8 for derating curves Maximum Baseplate Temperature, Tb 100 °C FEATURE CHARACTERISTICS Switching Frequency 165 190 215 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) On-State Voltage -1 0.8 V Off-State Voltage 2.4 18 V ON/OFF Control (Either Option) Application notes Figure B Pull-Up Voltage 10 V Pull-Up Resistance 30 kΩ Over-Temperature Shutdown OTP Trip Point 140 150 °C Average PCB Temperature Over-Temperature Shutdown Restart Hysteresis 10 °C Load Current Scale Factor 1333 See App Note: Output Load Current Calc. RELIABILITY CHARACTERISTICS Calculated MTBF (Telcordia) TR-NWT-000332 2.81 106 Hrs. 80% load, 200 LFM, 40 °C Ta Calculated MTBF (MIL-217) MIL-HDBK-217F 0.91 106 Hrs. 80% load, 200 LFM, 40 °C Ta Field Demonstrated MTBF 106 Hrs. See our website for details Note 1: UL’s product certification tests were carried out using 20 A 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 externally to the module. Product # BQ55120ETL16 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2BE552B Rev. E 03/21/16 Page 4 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Technical Specification Compliance & Testing Parameter Notes & Conditions STANDARDS COMPLIANCE UL 60950-1:2007/R:2011-12 Basic insulation EN 60950-1:2006/A2:2013 CAN/CSA C22.2 No. 60950-1:2007/A1:2011 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 # BQ55120ETL16 # 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, 95% RH, 1000 hours, continuous Vin applied except 5 min/day MIL-STD-883, method 2003 www.synqor.com Doc.# 005-2BE552B Rev. E 03/21/16 Page 5 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Technical Figures 100 11 10 9 Power Dissipation (W) Efficiency (%) 95 90 85 80 35 Vin 75 70 0 2 4 6 8 10 12 14 8 7 6 5 4 3 48 Vin 2 55 Vin 1 0 16 35 Vin 48 Vin 55 Vin 0 2 4 6 Load Current (A) 8 10 12 14 16 Load Current (A) Figure 1: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25 °C. Figure 2: Power dissipation at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25 °C. 97 14 13 12 Output Voltage (V) Efficiency (%) 96 95 94 11 10 9 8 25 C 35V 40 C 93 100 200 300 48V 7 55 C 6 400 55V 0 2 4 6 8 10 12 14 16 Load Current (A) Air Flow (LFM) Figure 3: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25 °C. Figure 4: Output voltage regualtion vs. load current for minimum, nominal, and maximum input voltage at 25 °C. 18 16 14 Iout (A) 12 10 8 6 400 LFM (2.0 m/s) 4 300 LFM (1.5 m/s) 200 LFM (1.0 m/s) 2 0 100 LFM (0.5 m/s) 0 25 40 55 70 Semiconductor junction temperature is within 1°C of surface temperature 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 3 to pin 1 (nominal input voltage). Product # BQ55120ETL16 Phone 1-888-567-9596 Figure 6: Thermal plot of converter at 16 A load current (192 W) with 55 °C 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.#005-2BE552B Rev. E 03/21/16 Page 6 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Technical Figures 18 16 14 Iout (A) 12 10 8 6 400 LFM (2.0 m/s) 4 300 LFM (1.5 m/s) 200 LFM (1.0 m/s) 2 0 100 LFM (0.5 m/s) 0 25 40 55 70 85 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 16 A load current (192 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) and 3 mF output capacitance (2.0 ms/div). 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 and 3 mF output capacitance (2 ms/ div). Input voltage pre-applied.. Ch 1: Vout (2 V/div), Ch 2: ON/OFF input (2 V/ div). Input Reflected Ripple Current Output Voltage Ripple Input Terminal Ripple Current source impedance iS iC DC-DC Converter VOUT VSOURCE electrolytic capacitor Figure 11: Output voltage response to step-change in load current (50%-75%50% of Iout(max); dI/dt = 0.1 A/µs). Load cap: 15 µF tantalum cap and 1 µF ceramic cap. Top trace: Vout (200 mV/div), Bottom trace: Iout (5 A/div). Product # BQ55120ETL16 Phone 1-888-567-9596 electrolytic capacitor ceramic capacitor 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.#005-2BE552B Rev. E 03/21/16 Page 7 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Technical Figures Figure 13: Input Terminal Ripple Current, ic, at full rated output current and nominal input voltage with 10 µH source impedance and 47 µF electrolytic capacitor (50 mA/div). See Figure 12. Figure 14: Input reflected ripple current, is, through a 10 µH source inductor, using a 47 µF electrolytic input capacitor (5 mA/div). See Figure 12. 14 Output Voltage (V) 12 10 8 6 4 35V 48V 2 0 55V 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 µF ceramic capacitor and 15 µF tantalum capacitor. Bandwidth: 20 MHz. See Figure 12. Figure 16: Output voltage vs. load current for different input voltages showing typcial current limit curves. 1 35 Vin Output Impedance (Ω ) 48 Vin 55 Vin 0.1 0.01 10 100 1,000 10,000 100,000 Hz Figure 17: Load current (10 A/div) as a function of time when the converter attempts to turn on into a 1 mΩ short circuit. Top trace (5.0 ms/div) is an expansion of the on-time portion of the bottom trace. Product # BQ55120ETL16 Phone 1-888-567-9596 Figure 18: Magnitude of incremental output impedance (Zout = Vout / Iout) for minimum, nominal, and maimum input voltage at full rated power. www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 8 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick 10 10 0 0 Reverse Transmission (dB) Forward Transmission (dB) Technical Figures -10 -20 35 Vin -30 48 Vin -10 -20 35 Vin -30 48 Vin 55 Vin -40 10 55 Vin 100 1,000 10,000 -40 100,000 Hz 10 100 1,000 10,000 100,000 Hz Figure 19: Magnitude of incremental forward transmission (FT = Vout / Vin) for minimum, nominal, and maimum input voltage at full rated power. Figure 20: Magnitude of incremental freverse transmission (RT = Iin / Iout) for minimum, nominal, and maimum input voltage at full rated power. 10000 Input Impedance (Ω ) 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 maimum input voltage at full rated power. Product # BQ55120ETL16 Phone 1-888-567-9596 www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 9 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Applications 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 a coarse 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 point 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. 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(+) 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: 12 V, 9 V, 7.5 V, 5 V, or 3.3 V. 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. 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. On/Off 9.5V 124k 5V 49.9k TTL 100k Vin(-) Figure B: Internal ON/OFF pin circuitry The BusQor architecture is very scalable, meaning multiple bus converters can be connected directly in parallel to allow current sharing for higher power applications. 3.3 V Front End 48 Vdc 35-55 V BusQor Converter 12 Vdc 2.5 V 1.8 V 1.5 V 0.9 V Typical User Board NiQor Converters Loads Figure A: Example of Intermediate Bus Architecture using BusQor bus converter and NiQor non-isolated converters Product # BQ55120ETL16 Phone 1-888-567-9596 www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 10 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Applications 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 after a typical period of 10 ms (see Figure C). The shutdown period lasts for a typical period of 250 ms (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 25 A 16 A Output Voltage 12 V 0V Time 10 ms Output Current 34 A peak Output Voltage < 12V 0V Time 250 ms 10 ms 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 34 A will flow into the short circuit for a period of about 10 ms. The output of the BusQor will shutdown to zero volts for the same period (Figure D). The shutdown period lasts for a period of 250 ms, at the end of which 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 4% (On) and 96% (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 48 V 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 0.1 A 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 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 # BQ55120ETL16 Phone 1-888-567-9596 www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 11 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Applications Section APPLICATION CONSIDERATIONS 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 3 ms is initiated. The output builds up to 90% or higher of the nominal voltage and stabilizes at the nominal value of 12 V. The rise time from 0 V to 90% is 1.5 ms typical. Figure F: Keep Out Areas for BusQor module At time t2, when the On/Off pin is de-asserted (disabled), the BusQor output instantly drops to 0V. Fall time from 12 V to 0 V 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 3 ms typical. Refer to the Control Features section of the data sheet for details on enabling and disabling methods for N and P logic type modules. 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. 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. Vin UVLO On/Off (N logic) OFF ON t0 t1 t2 t3 Vout t Vout Start-up Inhibit Fault Inhibit Time 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. Start-Up Figure E: Power Up/Down Diagram (not to scale) showing Start-Up Inhibit Period Product # BQ55120ETL16 Phone 1-888-567-9596 www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 12 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Applications Section Figure G: Location of Sense Resistor 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 1333 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 converter at zero load The number 1333 is a “Load Current Scale Factor” for this product, valid only for Vin = 48 V. Hence, measurement should be made at this input voltage. The voltage drop across the sense resistor is about 12 mV at full load of 16 A. Therefore, proper measuring techniques must be used to ensure accuracy. A calibrated DMM set to 300 mV 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”. + 1 Vin 2 3 1.5% 1.0% 0.5% 0.0% -0.5% -1.0% Module 1 -1.5% -2.0% Module 2 4 8 12 16 20 24 2 3 32 Figure I: Current share performance of 2 paralleled modules 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 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 J for details on PCB layout. Contact SynQor application engineering for further assistance on PCB trace design. 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 48 Vin. + BusQor module (N logic option) 12 V 32 A 4 48 BusQor module — 1 28 Total Load Current (A) 5 — BusQor module (N logic option) CM EMI filter 5 Bulk Cap BusQor module (Not shown in Figure H) 4 Figure H: BusQor Output Paralleling for increased current output Product # BQ55120ETL16 Deviation from 50/50 Sharing (%) 2.0% Phone 1-888-567-9596 Input LC filters Figure J: Recommended PCB layout for input circuit www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 13 Input: 35-55 V Output: 12 V Current: 16 A Package: Eighth-brick Ordering Information 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 0 E T L 1 6 N R S - G 6/6 RoHS Options (see Ordering Information) Output Current Model Number Input Voltage BQ55120ETL16xyz-G BQ50120ETL16xyz-G 35-55 V 43-52 V Output Voltage 12 V 12 V Max Output Current 16 A 16 A Thermal Design Performance Level Package Size The following options must be included in place of the w x y z spaces in the model numbers listed above. Output Voltage Input Voltage Options Description: x y z Enable Logic Pin Style Feature Set Product Family N - Negative P - Positive 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. K - 0.110" N - 0.145" R - 0.180" Y - 0.250" S - Standard 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]. Not all combinations make valid part numbers, please contact SynQor for availability. Contact SynQor for further information and to order: PATENTS Phone: Toll Free: Fax: E-mail: Web: Address: Product # BQ55120ETL16 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 SynQor holds numerous U.S. patents, one or more of which apply to most of its power converter products. Any that apply to the product(s) listed in this document are identified by markings on the product(s) or on internal components of the product(s) in accordance with U.S. patent laws. SynQor’s patents include the following: 5,999,417 6,222,742 6,545,890 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 8,149,597 8,493,751 8,644,027 9,143,042 WARRANTY SynQor offers a three (3) year limited warranty. Complete warranty information is listed on our website or is available upon request from SynQor. www.synqor.com Doc.#005-2BE552B Rev. E 03/21/16 Page 14