MQFL-28-2R5S

MQFL-28-2R5S Single Output H igH R eliability D C/DC C onveRteR Continuous Input 16-40V Transient Input 16-50V Output 2.5V Output to 40A 88% @ 20A / 87% @ 40A Efficiency F ull P oweR o PeRation : -55ºC The MilQor® series of high-reliability DC/DC converters brings SynQor’s field proven high-efficiency synchronous rectifier technology to the Military/Aerospace industry. SynQor’s innovative QorSealTM packaging approach ensures survivability in the most hostile environments. Compatible with the industry standard format, these converters operate at a fixed frequency, have no opto-isolators, and follow conservative component derating guidelines. They are designed and manufactured to comply with a wide range of military standards. Design Process MQFL series converters are: • Designed for reliability per NAVSO-P3641-A guidelines • Designed with components derated per: — MIL-HDBK-1547A — NAVSO P-3641A + 125ºC DesigneD & ManufactureD in the usa featuring Qorseal™ hi-rel asseMbly Features • • • • • • • • Fixed switching frequency No opto-isolators Parallel operation with current share Remote sense Clock synchronization Primary and secondary referenced enable Continuous short circuit and overload protection Input under-voltage lockout/over-voltage shutdown Qualification Process MQFL series converters are qualified to: • MIL-STD-810F — consistent with RTCA/D0-160E • SynQor’s First Article Qualification — consistent with MIL-STD-883F • SynQor’s Long-Term Storage Survivability Qualification • SynQor’s on-going life test Specification Compliance In-Line Manufacturing Process • • • • • • AS9100 and ISO 9001:2000 certified facility Full component traceability Temperature cycling Constant acceleration 24, 96, 160 hour burn-in Three level temperature screening Phone 1-888-567-9596 www.synqor.com MQFL series converters (with MQME filter) are designed to meet: • MIL-HDBK-704-8 (A through F) • RTCA/DO-160E Section 16 • MIL-STD-1275B • DEF-STAN 61-5 (part 6)/5 • MIL-STD-461 (C, D, E) • RTCA/DO-160E Section 22 Doc.# 005-2MQ250S Rev. B 03/19/09 Page 1 Product # MQFL-28-2R5S MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification BLOCK DIAGRAM TYPICAL CONNECTION DIAGRAM 1 2 3 28Vdc + – open means on +VIN IN RTN CASE ENA 1 SYNC OUT SYNC IN ENA 2 SHARE + SNS – SNS OUT RTN +VOUT 12 11 10 9 8 7 open means on 4 5 6 + Load – Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 2 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification MQFL-28-2R5S ELECTRICAL CHARACTERISTICS Parameter ABSOLUTE MAXIMUM RATINGS Min. Nom. Max. Units Notes & Conditions Vin=28V DC ±5%, Iout = 40A, CL = 0 µF, free running10 Subgroup13 unless otherwise specified Group A Input Voltage Non-Operating Operating 1 Reverse Bias (Tcase = 125ºC) Reverse Bias (Tcase = -55ºC) Isolation Voltage (input/output to case, input to output) Continuous Transient (≤100 µs) Operating Case Temperature 2 Storage Case Temperature Lead Temperature (20 sec) Voltage at ENA1, ENA2, SYNC IN Operating Input Voltage Range (continuous) Operating Input Voltage Range (transient, 1 sec) Input Under-Voltage Lockout 3 Turn-On Voltage Threshold Turn-Off Voltage Threshold Lockout Voltage Hysteresis Input Over-Voltage Shutdown 3 Turn-Off Voltage Threshold Turn-On Voltage Threshold Shutdown Voltage Hysteresis Maximum Input Current No Load Input Current (operating) Disabled Input Current (ENA1) Disabled Input Current (ENA2) Input Terminal Current Ripple (peak to peak) Output Voltage Set Point (Tcase = 25ºC) Output Voltage Set Point Over Temperature Output Voltage Line Regulation Output Voltage Load Regulation Total Output Voltage Range Output Voltage Ripple and Noise Peak to Peak Operating Output Current Range Operating Output Power Range Output DC Current-Limit Inception 4 Short Circuit Output Current Back-Drive Current Limit while Enabled Back-Drive Current Limit while Disabled Maximum Output Capacitance Output Voltage Deviation Load Transient 6 For a Positive Step Change in Load Current For a Negative Step Change in Load Current Settling Time (either case) 7 Output Voltage Deviation Line Transient 8 For a Positive Step Change in Line Voltage For a Negative Step Change in Line Voltage Settling Time (either case) 7 Turn-On Transient Output Voltage Rise Time Output Voltage Overshoot Turn-On Delay, Rising Vin 9 11 Turn-On Delay, Rising ENA1 11 Turn-On Delay, Rising ENA2 11 Iout = 40A (16Vin) Iout = 20A (16Vin) Iout = 40A (28Vin) Iout = 20A (28Vin) Iout = 40A (40Vin) Iout = 20A (40Vin) Load Fault Power Dissipation Short Circuit Power Dissipation 60 60 -0.8 -1.2 -500 -800 -55 -65 -1.2 16 16 14.75 13.80 0.50 54.0 50.0 2.0 28 28 15.50 14.40 1.10 56.8 51.4 5.3 110 2 25 40 2.47 2.46 -20 7 2.45 0 0 41 41 2.50 2.50 0 12 2.50 15 46 47 13 10 500 800 135 135 300 50 40 50 16.00 15.00 1.80 60.0 54.0 8.0 8 160 5 50 60 2.53 2.54 20 17 2.55 60 40 100 52 53 50 10,000 V V V V V V °C °C °C V V V V V V V V V A mA mA mA mA V V mV mV V mV A W A A A mA µF mV mV µs mV mV µs ms % ms ms ms % % % % % % W W 1, 2, 3 4, 5, 6 1, 2, 3 1, 2, 3 1, 2, 3 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3 3 3 3 3 3 3 3 INPUT CHARACTERISTICS Vin = 16V; Iout = 40A Vin = 16V, 28V, 50V Vin = 16V, 28V, 50V Bandwidth = 100 kHz – 10 MHz; see Figure 14 Vout at sense leads “ “ ; Vin = 16V, 28V, 50V “ ; Vout @ (Iout=0A) - Vout @ (Iout=40A) “ Bandwidth = 10 MHz; CL=11µF OUTPUT CHARACTERISTICS Vout ≤ 1.2V DYNAMIC CHARACTERISTICS 1 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 See Note 5 1, 2, 3 See Note 5 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 See Note 5 4, 5, 6 See Note 5 4, 5, 6 4, 5, 6 4, 5, 6 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3 3 3 3 3 3 3 3 -450 -300 300 200 450 350 250 250 500 10 2 8.0 6.0 3.0 Total Iout step = 20A ↔ 40A, 4A ↔ 20A; CL=11µF “ Vin step = 16V ↔ 50V; CL=11µF “ Vout = 0.25V → 2.25V ENA1, ENA2 = 5V ENA2 = 5V ENA1 = 5V -250 -250 250 6 0 5.5 3.0 1.5 EFFICIENCY 82 86 82 85 81 83 87 89 87 88 86 87 19 20 34 34 Iout at current limit inception point Vout ≤ 1.2V 4 Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 3 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification MQFL-28-2R5S ELECTRICAL CHARACTERISTICS (Continued) Parameter ISOLATION CHARACTERISTICS Min. Nom. Max. Units Notes & Conditions Vin=28V DC ±5%, Iout = 40A, CL = 0 µF, free running10 Subgroup13 unless otherwise specified 1 1 1 1 1 1 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 See Note 5 VSYNC OUT = 0.8V Output connected to SYNC IN of another MQFL converter Current drain required to ensure module is off Maximum current draw from pin allowed with module still on See Figure A See Note 5 See Note 5 1, 2, 3 See Note 5 1, 2, 3 See Note 5 1, 2, 3 Group A Isolation Voltage (dielectric strength) Input RTN to Output RTN Any Input Pin to Case Any Output Pin to Case Isolation Resistance (input rtn to output rtn) Isolation Resistance (any pin to case) Isolation Capacitance (input rtn to output rtn) Switching Frequency (free running) Synchronization Input Frequency Range Logic Level High Logic Level Low Duty Cycle Synchronization Output Pull Down Current Duty Cycle Enable Control (ENA1 and ENA2) Off-State Voltage Module Off Pulldown Current On-State Voltage Module On Pin Leakage Current Pull-Up Voltage Calculated MTBF (MIL-STD-217F2) GB @ Tcase=70ºC AIF @ Tcase=70ºC Demonstrated MTBF Device Weight 500 500 500 100 100 500 500 2 -0.5 20 20 25 80 2 3.2 FEATURE CHARACTERISTICS 44 550 600 700 10 0.8 80 75 0.8 20 4.5 V V V MW MW nF kHz kHz V V % mA % V µA V µA V 103 Hrs. 103 Hrs. 103 Hrs. g RELIABILITY CHARACTERISTICS 4.0 2800 440 TBD 79 WEIGHT CHARACTERISTICS Electrical Characteristics Notes 1. Converter will undergo input over-voltage shutdown. 2. Derate output power to 50% of rated power at Tcase = 135º C. 3. High or low state of input voltage must persist for about 200µs to be acted on by the lockout or shutdown circuitry. 4. Current limit inception is defined as the point where the output voltage has dropped to 90% of its nominal value. 5. Parameter not tested but guaranteed to the limit specified. 6. Load current transition time ≥ 10µs. 7. Settling time measured from start of transient to the point where the output voltage has returned to ±50mV of its final value. 8. Line voltage transition time ≥ 100µs. 9. Input voltage rise time ≤ 250µs. 10. Operating the converter at a synchronization frequency above the free running frequency will cause the converter’s efficiency to be slightly reduced and it may also cause a slight reduction in the maximum output current/power available. For more information consult the factory. 11. After a disable or fault event, module is inhibited from restarting for 300ms. See Shut Down section on Page 9. 12. SHARE pin outputs a power failure warning pulse during a fault condition. See Current Share section on Page 11. 13. Only the ES and HB grade products are tested at three temperatures. The B and C grade products are tested at one temperature. Please refer to the ESS table on Page 13 for details. 14. These derating curves apply for the ES- and HB- grade products. The C- grade product has a maximum case temperature of 100º C and a maximum junction temperature rise of 20º C above TCASE. The B- grade product has a maximum case temperature of 85º C and a maximum junction temperature rise of 20º C at full load. Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 4 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification 100 95 90 100 95 90 Efficiency (%) Efficiency (%) 16 Vin 28 Vin 40 Vin 85 80 75 70 65 60 0 5 10 15 20 25 30 35 40 85 80 75 70 65 60 -55ºC 25ºC 125ºC 16 Vin 28 Vin 40 Vin Load Current (A) Case Temperature (ºC) Figure 1: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at Tcase=25°C. Figure 2: Efficiency at nominal output voltage and 60% rated power vs. case temperature for input voltage of 16V, 28V, and 40V. 20 18 16 16 14 Power Dissipation (W) 14 12 10 8 6 4 2 0 0 5 10 15 20 25 30 35 40 16 Vin 28 Vin 40 Vin Power Dissipation (W) 12 10 8 6 4 2 0 -55ºC 25ºC 125ºC 16 Vin 28 Vin 40 Vin Load Current (A) Case Temperature (ºC) Figure 3: Power dissipation at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at Tcase=25°C. Figure 4: Power dissipation at nominal output voltage and 60% rated power vs. case temperature for input voltage of 16V, 28V, and 40V. 50 45 40 35 125 3.0 100 2.5 Output Voltage (V) 2.0 25 20 15 10 5 0 25 45 65 85 105 125 135 50 Pout (W) Iout (A) 30 75 1.5 1.0 Tjmax = 105ºC Tjmax = 125ºC Tjmax = 145ºC 25 0.5 28 Vin 0 145 0.0 0 5 10 15 20 25 30 35 40 45 50 Case Temperature (ºC) Load Current (A) Figure 5: Output Current / Output Power derating curve as a function of Tcase and the Maximum desired power MOSFET junction temperature at Vin = 28V (see Note 14). Product # MQFL-28-2R5S Phone 1-888-567-9596 Figure 6: Output voltage vs. load current showing typical current limit curves. www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 5 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification Figure 7: Turn-on transient at full resistive load and zero output capacitance initiated by ENA1. Input voltage pre-applied. Ch 1: Vout (500mV/ div). Ch 2: ENA1 (5V/div). Figure 8: Turn-on transient at full resistive load and 10mF output capacitance initiated by ENA1. Input voltage pre-applied. Ch 1: Vout (500mV/ div). Ch 2: ENA1 (5V/div). Figure 9: Turn-on transient at full resistive load and zero output capacitance initiated by ENA2. Input voltage pre-applied. Ch 1: Vout (500mV/ div). Ch 2: ENA2 (5V/div). Figure 10: Turn-on transient at full resistive load and zero output capacitance initiated by Vin. ENA1 and ENA2 both previously high. Ch 1: Vout (500mV/div). Ch 2: Vin (10V/div). Figure 11: Output voltage response to step-change in load current 50%100%-50% of Iout (max). Load cap: 1µF ceramic cap and 10µF, 100mΩ ESR tantalum cap. Ch 1: Vout (200mV/div). Ch 2: Iout (20A/div). Product # MQFL-28-2R5S Phone 1-888-567-9596 Figure 12: Output voltage response to step-change in load current 0%-50%-0% of Iout (max). Load cap: 1µF ceramic cap and 10µF, 100 mΩ ESR tantalum cap. Ch 1: Vout (200mV/div). Ch 2: Iout (20A/div). Doc.# 005-2MQ250S Rev. B 03/19/09 Page 6 www.synqor.com MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification See Fig. 15 See Fig. 16 MQME Filter VSOURCE iC MQFL Converter 1 µF VOUT 10 µF, ceramic 100mW ESR capacitor capacitor Figure 13: Output voltage response to step-change in input voltage (16V 50V - 16V). Load cap: 10µF, 100mΩ ESR tantalum cap and 1µF ceramic cap. Ch 1: Vout (200mV/div). Ch 2: Vin (20V/div). Figure 14: Test set-up diagram showing measurement points for Input Terminal Ripple Current (Figure 15) and Output Voltage Ripple (Figure 16). Figure 15: Input terminal current ripple, ic, at full rated output current and nominal input voltage with SynQor MQ filter module (50mA/div). Bandwidth: 20MHz. See Figure 14. Figure 16: Output voltage ripple, Vout, at nominal input voltage and rated load current (20mV/div). Load capacitance: 1µF ceramic capacitor and 10µF tantalum capacitor. Bandwidth: 10MHz. See Figure 14. Figure 17: Rise of output voltage after the removal of a short circuit across the output terminals. Ch 1: Vout (500mV/div). Ch 2: Iout (20A/div). Product # MQFL-28-2R5S Phone 1-888-567-9596 Figure 18: SYNC OUT vs. time, driving SYNC IN of a second SynQor MQFL converter. Ch1: SYNC OUT: (1V/div). www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 7 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification 0.1 0 -10 Forward Transmission (dB) Output Impedance (ohms) -20 -30 -40 -50 -60 -70 -80 -90 16Vin 28Vin 40Vin 10 100 1,000 10,000 100,000 0.01 0.001 16Vin 28Vin 40Vin 0.0001 10 100 1,000 10,000 100,000 -100 Hz Hz Figure 19: Magnitude of incremental output impedance (Zout = vout/iout) for minimum, nominal, and maximum input voltage at full rated power. Figure 20: Magnitude of incremental forward transmission (FT = vout/vin) for minimum, nominal, and maximum input voltage at full rated power. 10 100 0 Reverse Transmission (dB) Input Impedance (ohms) 10 -10 -20 1 -30 16Vin 28Vin 40Vin -50 10 100 1,000 10,000 100,000 0.1 16Vin 28Vin 40Vin -40 0.01 10 100 1,000 10,000 100,000 Hz Hz Figure 21: Magnitude of incremental reverse transmission (RT = iin/iout) for minimum, nominal, and maximum input voltage at full rated power. Figure 22: Magnitude of incremental input impedance (Zin = vin/iin) for minimum, nominal, and maximum input voltage at full rated power. Figure 23: High frequency conducted emissions of standalone MQFL-2805S, 5Vout module at 120W output, as measured with Method CE102. Limit line shown is the ‘Basic Curve’ for all applications with a 28V source. Product # MQFL-28-2R5S Phone 1-888-567-9596 Figure 24: High frequency conducted emissions of MQFL-28-05S, 5Vout module at 120W output with MQFL-28-P filter, as measured with Method CE102. Limit line shown is the ‘Basic Curve’ for all applications with a 28V source. Doc.# 005-2MQ250S Rev. B 03/19/09 Page 8 www.synqor.com MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification BASIC OPERATION AND FEATURES The MQFL DC/DC converter uses a two-stage power conversion topology. The first, or regulation, stage is a buck-converter that keeps the output voltage constant over variations in line, load, and temperature. The second, or isolation, stage uses transformers to provide the functions of input/output isolation and voltage transformation to achieve the output voltage required. Both the regulation and the isolation stages switch at a fixed frequency for predictable EMI performance. The isolation stage switches at one half the frequency of the regulation stage, but due to the push-pull nature of this stage it creates a ripple at double its switching frequency. As a result, both the input and the output of the converter have a fundamental ripple frequency of about 550 kHz in the free-running mode. Rectification of the isolation stage’s output is accomplished with synchronous rectifiers. These devices, which are MOSFETs with a very low resistance, dissipate far less energy than would Schottky diodes. This is the primary reason why the MQFL converters have such high efficiency, particularly at low output voltages. Besides improving efficiency, the synchronous rectifiers permit operation down to zero load current. There is no longer a need for a minimum load, as is typical for converters that use diodes for rectification. The synchronous rectifiers actually permit a negative load current to flow back into the converter’s output terminals if the load is a source of short or long term energy. The MQFL converters employ a “back-drive current limit” to keep this negative output terminal current small. There is a control circuit on both the input and output sides of the MQFL converter that determines the conduction state of the power switches. These circuits communicate with each other across the isolation barrier through a magnetically coupled device. No optoisolators are used. A separate bias supply provides power to both the input and output control circuits. Among other things, this bias supply permits the converter to operate indefinitely into a short circuit and to avoid a hiccup mode, even under a tough start-up condition. An input under-voltage lockout feature with hysteresis is provided, as well as an input over-voltage shutdown. There is also an output current limit that is nearly constant as the load impedance decreases to a short circuit (i.e., there is not foldback or fold-forward characteristic to the output current under this condition). When a load fault is removed, the output voltage rises exponentially to its nominal value without an overshoot. The MQFL converter’s control circuit does not implement an output over-voltage limit or an over-temperature shutdown. The following sections describe the use and operation of additional control features provided by the MQFL converter. Product # MQFL-28-2R5S Phone 1-888-567-9596 CONTROL FEATURES ENABLE: The MQFL converter has two enable pins. Both must have a logic high level for the converter to be enabled. A logic low on either pin will inhibit the converter. The ENA1 pin (pin 4) is referenced with respect to the converter’s input return (pin 2). The ENA2 pin (pin 12) is referenced with respect to the converter’s output return (pin 8). This permits the converter to be inhibited from either the input or the output side. Regardless of which pin is used to inhibit the converter, the regulation and the isolation stages are turned off. However, when the converter is inhibited through the ENA1 pin, the bias supply is also turned off, whereas this supply remains on when the converter is inhibited through the ENA2 pin. A higher input standby current therefore results in the latter case. Both enable pins are internally pulled high so that an open connection on both pins will enable the converter. Figure A shows the equivalent circuit looking into either enable pins. It is TTL compatible. Figure A: Equivalent circuit looking into either the ENA1 or ENA2 pins with respect to its corresponding return pin. SHUT DOWN: The MQFL converter will shut down in response to only four conditions: ENA1 input low, ENA2 input low, VIN input below under-voltage lockout threshold, or VIN input above over-voltage shutdown threshold. Following a shutdown event, there is a startup inhibit delay which will prevent the converter from restarting for approximately 300ms. After the 300ms delay elapses, if the enable inputs are high and the input voltage is within the operating range, the converter will restart. If the VIN input is brought down to nearly 0V and back into the operating range, there is no startup inhibit, and the output voltage will rise according to the “Turn-On Delay, Rising Vin” specification. www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 9 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification REMOTE SENSE: The purpose of the remote sense pins is to correct for the voltage drop along the conductors that connect the converter’s output to the load. To achieve this goal, a separate conductor should be used to connect the +SENSE pin (pin 10) directly to the positive terminal of the load, as shown in the connection diagram on Page 2. Similarly, the –SENSE pin (pin 9) should be connected through a separate conductor to the return terminal of the load. NOTE: Even if remote sensing of the load voltage is not desired, the +SENSE and the -SENSE pins must be connected to +Vout (pin 7) and OUTPUT RETURN (pin 8), respectively, to get proper regulation of the converter’s output. If they are left open, the converter will have an output voltage that is approximately 200mV higher than its specified value. If only the +SENSE pin is left open, the output voltage will be approximately 25mV too high. Inside the converter, +SENSE is connected to +Vout with a resistor value from 100W to 274W, depending on output voltage, and –SENSE is connected to OUTPUT RETURN with a 10W resistor. It is also important to note that when remote sense is used, the voltage across the converter’s output terminals (pins 7 and 8) will be higher than the converter’s nominal output voltage due to resistive drops along the connecting wires. This higher voltage at the terminals produces a greater voltage stress on the converter’s internal components and may cause the converter to fail to deliver the desired output voltage at the low end of the input voltage range at the higher end of the load current and temperature range. Please consult the factory for details. SYNCHRONIZATION: The MQFL converter’s switching frequency can be synchronized to an external frequency source that is in the 500 kHz to 700 kHz range. A pulse train at the desired frequency should be applied to the SYNC IN pin (pin 6) with respect to the INPUT RETURN (pin 2). This pulse train should have a duty cycle in the 20% to 80% range. Its low value should be below 0.8V to be guaranteed to be interpreted as a logic low, and its high value should be above 2.0V to be guaranteed to be interpreted as a logic high. The transition time between the two states should be less than 300ns. If the MQFL converter is not to be synchronized, the SYNC IN pin should be left open circuit. The converter will then operate in its free-running mode at a frequency of approximately 550 kHz. If, due to a fault, the SYNC IN pin is held in either a logic low or logic high state continuously, the MQFL converter will revert to its free-running frequency. The MQFL converter also has a SYNC OUT pin (pin 5). This output can be used to drive the SYNC IN pins of as many as ten (10) other MQFL converters. The pulse train coming out of SYNC OUT has a duty cycle of 50% and a frequency that matches the switching frequency of the converter with which it is associated. Product # MQFL-28-2R5S Phone 1-888-567-9596 This frequency is either the free-running frequency if there is no synchronization signal at the SYNC IN pin, or the synchronization frequency if there is. The SYNC OUT signal is available only when the DC input voltage is above approximately 12V and when the converter is not inhibited through the ENA1 pin. An inhibit through the ENA2 pin will not turn the SYNC OUT signal off. NOTE: An MQFL converter that has its SYNC IN pin driven by the SYNC OUT pin of a second MQFL converter will have its start of its switching cycle delayed approximately 180 degrees relative to that of the second converter. Figure B shows the equivalent circuit looking into the SYNC IN pin. Figure C shows the equivalent circuit looking into the SYNC OUT pin. Figure B: Equivalent circuit looking into the SYNC IN pin with respect to the IN RTN (input return) pin. Figure C: Equivalent circuit looking into SYNC OUT pin with respect to the IN RTN (input return) pin. CURRENT SHARE: When several MQFL converters are placed in parallel to achieve either a higher total load power or N+1 redundancy, their SHARE pins (pin 11) should be connected together. The voltage on this common SHARE node represents the average current delivered by all of the paralleled converters. Each converter monitors this average value and adjusts itself so that its output current closely matches that of the average. Doc.# 005-2MQ250S Rev. B 03/19/09 Page 10 www.synqor.com MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification Since the SHARE pin is monitored with respect to the OUTPUT RETURN (pin 8) by each converter, it is important to connect all of the converters’ OUTPUT RETURN pins together through a low DC and AC impedance. When this is done correctly, the converters will deliver their appropriate fraction of the total load current to within +/- 10% at full rated load. Whether or not converters are paralleled, the voltage at the SHARE pin could be used to monitor the approximate average current delivered by the converter(s). A nominal voltage of 1.0V represents zero current and a nominal voltage of 2.2V represents the maximum rated current, with a linear relationship in between. The internal source resistance of a converter’s SHARE pin signal is 2.5 kW. During an input voltage fault or primary disable event, the SHARE pin outputs a power failure warning pulse. The SHARE pin will go to 3V for approximately 14ms as the output voltage falls. NOTE: Converters operating from separate input filters with reverse polarity protection (such as the MQME-28-T filter) with their outputs connected in parallel may exhibit hiccup operation at light loads. Consult factory for details. OUTPUT VOLTAGE TRIM: If desired, it is possible to increase the MQFL converter’s output voltage above its nominal value. To do this, use the +SENSE pin (pin 10) for this trim function instead of for its normal remote sense function, as shown in Figure D. In this case, a resistor connects the +SENSE pin to the –SENSE pin (which should still be connected to the output return, either remotely or locally). The value of the trim resistor should be chosen according to the following equation or from Figure E: Rtrim = 407.5 Vout – Vnom – 0.025 Figure E: Output Voltage Trim Graph As the output voltage is trimmed up, it produces a greater voltage stress on the converter’s internal components and may cause the converter to fail to deliver the desired output voltage at the low end of the input voltage range at the higher end of the load current and temperature range. Please consult the factory for details. Factory trimmed converters are available by request. INPUT UNDER-VOLTAGE LOCKOUT: The MQFL converter has an under-voltage lockout feature that ensures the converter will be off if the input voltage is too low. The threshold of input voltage at which the converter will turn on is higher that the threshold at which it will turn off. In addition, the MQFL converter will not respond to a state of the input voltage unless it has remained in that state for more than about 200µs. This hysteresis and the delay ensure proper operation when the source impedance is high or in a noisy environment. INPUT OVER-VOLTAGE SHUTDOWN: The MQFL converter also has an over-voltage feature that ensures the converter will be off if the input voltage is too high. It also has a hysteresis and time delay to ensure proper operation. 12 11 10 9 8 7 Load + Rtrim where: Vnom = the converter’s nominal output voltage, Vout = the desired output voltage (greater than Vnom), and Rtrim is in Ohms. 1 2 3 28Vdc + – open means on +VIN IN RTN CASE ENA 1 SYNC OUT SYNC IN ENA 2 SHARE + SNS – SNS OUT RTN +VOUT 4 5 6 – Figure D: Typical connection for output voltage trimming. Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 11 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification BACK-DRIVE CURRENT LIMIT: Converters that use MOSFETs as synchronous rectifiers are capable of drawing a negative current from the load if the load is a source of short- or long-term energy. This negative current is referred to as a “back-drive current”. Conditions where back-drive current might occur include paralleled converters that do not employ current sharing, or where the current share feature does not adequately ensure sharing during the startup or shutdown transitions. It can also occur when converters having different output voltages are connected together through either explicit or parasitic diodes that, while normally off, become conductive during startup or shutdown. Finally, some loads, such as motors, can return energy to their power rail. Even a load capacitor is a source of back-drive energy for some period of time during a shutdown transient. To avoid any problems that might arise due to back-drive current, the MQFL converters limit the negative current that the converter can draw from its output terminals. The threshold for this backdrive current limit is placed sufficiently below zero so that the converter may operate properly down to zero load, but its absolute value (see the Electrical Characteristics page) is small compared to the converter’s rated output current. THERMAL CONSIDERATIONS: Figure 5 shows the suggested Power Derating Curves for this converter as a function of the case temperature and the maximum desired power MOSFET junction temperature. All other components within the converter are cooler than its hottest MOSFET, which at full power is no more than 20ºC higher than the case temperature directly below this MOSFET. The Mil-HDBK-1547A component derating guideline calls for a maximum component temperature of 105ºC. Figure 5 therefore has one power derating curve that ensures this limit is maintained. It has been SynQor’s extensive experience that reliable long-term converter operation can be achieved with a maximum component temperature of 125ºC. In extreme cases, a maximum temperature of 145ºC is permissible, but not recommended for long-term operation where high reliability is required. Derating curves for these higher temperature limits are also included in Figure 5. The maximum case temperature at which the converter should be operated is 135ºC. When the converter is mounted on a metal plate, the plate will help to make the converter’s case bottom a uniform temperature. How well it does so depends on the thickness of the plate and on the thermal conductance of the interface layer (e.g. thermal grease, thermal pad, etc.) between the case and the plate. Unless this is done very well, it is important not to mistake the plate’s temperature for the maximum case temperature. It is easy for them to be as much as 5-10ºC different at full power and at high temperatures. It is suggested that a thermocouple be attached directly to the converter’s case through a small hole in the plate when investigating how hot the converter is getting. Care must also be made to ensure that there is not a large thermal resistance between the thermocouple and the case due to whatever adhesive might be used to hold the thermocouple in place. INPUT SYSTEM INSTABILITY: This condition can occur because any DC/DC converter appears incrementally as a negative resistance load. A detailed application note titled “Input System Instability” is available on the SynQor website which provides an understanding of why this instability arises, and shows the preferred solution for correcting it. Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 12 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification CONSTRUCTION AND ENVIRONMENTAL STRESS SCREENING OPTIONS ES-Grade (-55 ºC to +125 ºC) (Element Evaluation) Yes Condition B (-55 ºC to +125 ºC) 500g HB-Grade (-55 ºC to +125 ºC) (Element Evaluation) Yes Condition C (-65 ºC to +150 ºC) Condition A (5000g) Screening Internal Visual Temperature Cycle Constant Acceleration Consistent with MIL-STD-883F B-Grade (-40 ºC to +85 ºC) Yes No No C-Grade (-40 ºC to +100 ºC) Yes No No * Method 1010 Method 2001 (Y1 Direction) Method 1015 Load Cycled • 10s period • 2s @ 100% Load • 8s @ 0% Load Method 5005 (Group A) Burn-in 12 Hrs @ +100 ºC 24 Hrs @ +125 ºC 96 Hrs @ +125 ºC 160 Hrs @ +125 ºC Final Electrical Test Mechanical Seal, Thermal, and Coating Process External Visual Construction Process +25 ºC +25 ºC -45, +25, +100 ºC -55, +25, +125 ºC Anodized Package Full QorSeal Full QorSeal Full QorSeal 2009 * Ruggedized * QorSeal Yes QorSeal Yes QorSeal * Per IPC-A-610 (Rev. D) Class 3 MilQor converters and filters are offered in four variations of construction technique and environmental stress screening options. The three highest grades, C, ES, and HB, all use SynQor’s proprietary QorSeal™ Hi-Rel assembly process that includes a Parylene-C coating of the circuit, a high performance thermal compound filler, and a nickel barrier gold plated aluminum case. The B-grade version uses a ruggedized assembly process that includes a medium performance thermal compound filler and a black anodized aluminum case†. Each successively higher grade has more stringent mechanical and electrical testing, as well as a longer burn-in cycle. The ES- and HB-Grades are also constructed of components that have been procured through an element evaluation process that pre-qualifies each new batch of devices. † Note: Since the surface of the black anodized case is not guaranteed to be electrically conductive, a star washer or similar device should be used to cut through the surface oxide if electrical connection to the case is desired. Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 13 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification 0.093 [2.36] 1 2 3 4 5 6 +VIN IN RTN CASE ENA 1 SYNC OUT SYNC IN ENA 2 SHARE MQFL-28-2R5S-X-HB DC/DC CONVERTER 28Vin 2.5Vout @ 40A MADE IN USA +SNS -SNS OUT RTN +VOUT S/N 0000000 D/C 3205-301 CAGE 1WX10 12 11 10 9 8 7 0.250 [6.35] 1.50 [38.10] 1.260 [32.00] 0.200 [5.08] TYP. NON-CUM. 0.040 [1.02] PIN 0.128 [3.25] 0.050 [1.27] 0.220 [5.59] 0.228 [5.79] 2.50 [63.50] 2.76 [70.10] 3.00 [76.20] 2.96 [75.2] 0.390 [9.91] Case X 0.093 [2.36] 1 2 3 4 5 6 +VIN IN RTN CASE ENA 1 SYNC OUT SYNC IN ENA 2 SHARE MQFL-28-2R5S-U-HB DC/DC CONVERTER 28Vin 2.5Vout @ 40A MADE IN USA +SNS -SNS OUT RTN +VOUT S/N 0000000 D/C 3205-301 CAGE 1WX10 12 11 10 9 8 7 0.250 [6.35] 1.260 [32.00] 1.50 [38.10] 0.200 [5.08] TYP. NON-CUM. 0.040 [1.02] PIN 0.128 [3.25] 0.42 [10.7] 0.050 [1.27] 0.220 [5.59] 2.50 [63.50] 2.76 [70.10] 3.00 [76.20] 2.80 [71.1] 0.390 [9.91] NOTES 1) 2) 3) 4) 5) 6) Pins 0.040” (1.02mm) diameter Pins Material: Copper Finish: Gold over Nickel plate All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm) x.xxx +/-0.010 in. (x.xx +/-0.25mm) Weight: 2.8 oz (78.5 g) typical Workmanship: Meets or exceeds IPC-A-610C Class III Print Labeling on Top Surface per Product Label Format Drawing Case U PIN DESIGNATIONS Pin Function 1 2 3 4 5 6 Positive input Input return CASE Enable 1 Sync output Sync input Pin Function 7 8 9 Positive output Output return - Sense 10 + Sense 11 Share 12 Enable 2 03/19/09 Page 14 Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification 0.250 [6.35] TYP 1 2 3 4 5 6 +VIN IN RTN CASE ENA 1 SYNC OUT SYNC IN 1.15 [29.21] 0.300 [7.62] 0.140 [3.56] 0.250 [6.35] ENA 2 SHARE MQFL-28-2R5S-Y-HB DC/DC CONVERTER 28Vin 2.5Vout @ 40A MADE IN USA +SNS -SNS OUT RTN +VOUT S/N 0000000 D/C 3205-301 CAGE 1WX10 12 2.00 11 [50.80] 10 1.50 9 [38.10] 8 1.750 7 [44.45] 0.200 [5.08] TYP. NON-CUM. 0.040 [1.02] PIN 0.050 [1.27] 0.220 [5.59] 1.750 [44.45] 2.50 [63.50] 2.96 [75.2] 0.375 [9.52] 0.228 [5.79] 0.390 [9.91] Case Y Case W (variant of Y) 0.200 [5.08] TYP. NON-CUM. 0.250 [6.35] Case Z (variant of Y) 0.200 [5.08] TYP. NON-CUM. 0.250 [6.35] 0.040 [1.02] PIN 0.220 [5.59] 0.050 [1.27] 0.390 [9.91] 0.525 [13.33] 2.80 [71.1] NOTES 1) 2) 3) 4) 5) 6) Pins 0.040” (1.02mm) diameter Pins Material: Copper Finish: Gold over Nickel plate All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm) x.xxx +/-0.010 in. (x.xx +/-0.25mm) Weight: 2.8 oz (78.5 g) typical Workmanship: Meets or exceeds IPC-A-610C Class III Print Labeling on Top Surface per Product Label Format Drawing 0.040 [1.02] PIN 0.420 [10.7] 0.050 [1.27] 0.220 [5.59] 2.80 [71.1] 0.525 [13.33] 0.390 [9.91] PIN DESIGNATIONS Pin Function 1 2 3 4 5 6 Positive input Input return CASE Enable 1 Sync output Sync input Pin Function 7 8 9 10 11 12 Positive output Output return - Sense + Sense Share Enable 2 Page 15 0.36 [9.2] Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification MilQor MQFL FAMILY MATRIX The tables below show the array of MQFL converters available. When ordering SynQor converters, please ensure that you use the complete part number according to the table in the last page. Contact the factory for other requirements. Single Output MQFL-28 16-40Vin Cont. 16-50Vin 1s Trans.* Absolute Max Vin = 60V 1.5V (1R5S) 40A 1.8V (1R8S) 40A 2.5V (2R5S) 40A 3.3V (3R3S) 30A 5V (05S) 24A 6V (06S) 20A 7.5V (7R5S) 16A 9V (09S) 13A 12V (12S) 10A 15V (15S) 8A 28V (28S) 4A MQFL-28E 16-70Vin Cont. 16-80Vin 1s Trans.* Absolute Max Vin =100V 40A 40A 40A 30A 24A 20A 16A 13A 10A 8A 4A MQFL-28V 16-40Vin Cont. 5.5-50Vin 1s Trans.* Absolute Max Vin = 60V 40A 40A 40A 30A 20A 17A 13A 11A 8A 6.5A 3.3A MQFL-28VE 16-70Vin Cont. 5.5-80Vin 1s Trans.* Absolute Max Vin = 100V 40A 40A 40A 30A 20A 17A 13A 11A 8A 6.5A 3.3A MQFL-270 155-400Vin Cont. 155-475Vin 0.1s Trans.* Absolute Max Vin = 550V 40A 40A 40A 30A 24A 20A 16A 13A 10A 8A 4A MQFL-270E 130-475Vin Cont. 130-520Vin 0.1s Trans.* Absolute Max Vin = 600V 40A 40A 40A 30A 20A 17A 13A 11A 8A 6.5A 3.3A MQFL-270L 65-350Vin Cont. 65-475Vin 0.1s Trans.* Absolute Max Vin = 550V 40A 40A 30A 22A 15A 12A 10A 8A 6A 5A 2.7A Dual Output MQFL-28 16-40Vin Cont. 16-50Vin 1s Trans.* Absolute Max Vin = 60V 5V (05D) 24A Total 12V (12D) 10A Total 15V (15D) 8A Total Triple Output MQFL-28 16-40Vin Cont. 16-50Vin 1s Trans.* Absolute Max Vin = 60V 3.3V/±12V (3R312T) 22A/ ±1A 3.3V/±15V (3R315T) 22A/ ±0.8A 5V/±12V (0512T) 15A/ ±1A 5V/±15V (0515T) 15A/ ±0.8A 30V/±15V (3015T) 2.5A/ ±0.8A MQFL-28E 16-70Vin Cont. 16-80Vin 1s Trans.* Absolute Max Vin =100V MQFL-28E 24A Total 10A Total 8A Total 16-70Vin Cont. 16-80Vin 1s Trans.* Absolute Max Vin =100V 22A/ ±1A 22A/ ±0.8A 15A/ ±1A 15A/ ±0.8A 2.5A/ ±0.8A MQFL-28V 16-40Vin Cont. 5.5-50Vin 1s Trans.* Absolute Max Vin = 60V MQFL-28V 20A Total 8A Total 6.5A Total 16-40Vin Cont. 5.5-50Vin 1s Trans.* Absolute Max Vin = 60V 22A/ ±1A 22A/ ±0.8A 15A/ ±1A 15A/ ±0.8A 2.5A/ ±0.8A MQFL-28VE 16-70Vin Cont. 5.5-80Vin 1s Trans.* Absolute Max Vin = 100V MQFL-28VE 20A Total 8A Total 6.5A Total 16-70Vin Cont. 5.5-80Vin 1s Trans.* Absolute Max Vin = 100V 22A/ ±1A 22A/ ±0.8A 15A/ ±1A 15A/ ±0.8A 2.5A/ ±0.8A MQFL-270 155-400Vin Cont. 155-475Vin 0.1s Trans.* Absolute Max Vin = 550V MQFL-270 24A Total 10A Total 8A Total 155-400Vin Cont. 155-475Vin 0.1s Trans.* Absolute Max Vin = 550V 22A/ ±1A 22A/ ±0.8A 15A/ ±1A 15A/ ±0.8A 2.5A/ ±0.8A MQFL-270E 130-475Vin Cont. 130-520Vin 0.1s Trans.* Absolute Max Vin = 600V MQFL-270E 20A Total 8A Total 6.5A Total 130-475Vin Cont. 130-520Vin 0.1s Trans.* Absolute Max Vin = 600V 22A/ ±1A 22A/ ±1A 22A/ ±0.8A 22A/ ±0.8A 15A/ ±1A 15A/ ±1A 15A/ ±0.8A 15A/ ±0.8A 2.5A/ ±0.8A 2.5A/ ±0.8A MQFL-270L 65-350Vin Cont. 65-475Vin 0.1s Trans.* Absolute Max Vin = 550V MQFL-270L 15A Total 6A Total 5A Total 65-350Vin Cont. 65-475Vin 0.1s Trans.* Absolute Max Vin = 550V (75Wmax Total Output Power) *Converters may be operated continuously at the highest transient input voltage, but some component electrical and thermal stresses would be beyond MIL-HDBK-1547A guidelines. Product # MQFL-28-2R5S Phone 1-888-567-9596 www.synqor.com †80% of total output current available on any one output. 03/19/09 Page 16 Doc.# 005-2MQ250S Rev. B MQFL-28-2R5S Output: 2.5 V Current: 40 A Technical Specification PART NUMBERING SYSTEM The part numbering system for SynQor’s MilQor DC-DC converters follows the format shown in the table below. Input Voltage Range Output Voltage(s) Single Output Dual Output Triple Output Model Name Package Outline/ Pin Configuration Screening Grade MQFL 28 28E 28V 28VE 270 270E 270L 1R5S 1R8S 2R5S 3R3S 05S 06S 7R5S 09S 12S 15S 28S 05D 12D 15D 3R312T 3R315T 0512T 0515T 3015T U X Y W Z B C ES HB Example: APPLICATION NOTES MQFL – 28VE – 2R5S – Y – ES A variety of application notes and technical white papers can be downloaded in pdf format from the SynQor website. PATENTS SynQor holds the following patents, one or more of which might apply to this product: 5,999,417 6,594,159 6,927,987 7,119,524 6,222,742 6,731,520 7,050,309 7,269,034 6,545,890 6,894,468 7,072,190 7,272,021 6,577,109 6,896,526 7,085,146 7,272,023 Contact SynQor for further information: Phone: Toll Free: Fax: E-mail: Web: Address: 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 two (2) 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. Product # MQFL-28-2R5S www.synqor.com Doc.# 005-2MQ250S Rev. B 03/19/09 Page 17