High Reliability DC-DC Converter 65-350 V Continuous Input Full Power Operation: -550C to +1250C 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 QorSeal® 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. MQFL series converters are: • Designed for reliability per NAVSO-P3641-A guidelines • Designed with components derated per: — MIL-HDBK-1547A — NAVSO P-3641A Features 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 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 with auto-restart feature Input under-voltage and over-voltage shutdown Specification Compliance • AS9100 and ISO 9001 certified facility • Full component traceability • Temperature cycling • Constant acceleration • 24, 96, 160 hour burn-in • Three level temperature screening MQFL series converters (with MQME filter) are designed to meet: • MIL-HDBK-704-7 (A through F) • RTCA/DO-160 Section 16, 17, 18 • MIL-STD-1275 (B, D) • DEF-STAN 61-5 (part 6)/(5, 6) • MIL-STD-461 (C, D, E, F) • RTCA/DO-160(E, F, G) Section 22

]®0©@Qblock diagram (Tp'YYYY +Vin ®- INPUT RETURN CURRENT SENSE ISOLATION STAGE OUTPUT RETURN GATE DRIVERS UVLO OVSD CURRENT LIMIT PRIMARY CONTROL SECONDARY CONTROL BIAS POWER CONTROL POWER -0 ENABLE 2 0 SHARE 0 + SENSE typical connection diagram 270 Vdc open 5 (-TL) +vin in rtn case ena 1 sync out sync in mqfl ena 2 share +sns -sns out rtn +vout

MQFL-270L-05SJ Output: 5 V yi^y Current: 15 A MQFL-270L-05S ELECTR Parameter Specifications subject to change without notice

MQFL-270L-05SJ Output: 5 V yi^y Current: 15 A MQFL-270L-05S ELECTR Parameter Specifications subject to change without notice Electrical Characteristics Notes 1. Converter will undergo input over-voltage shutdown. 2. Derate output power to 50% of rated power at Tcase = 135 °C. 135 °C is above specified operating range. 3. High or low state of input voltage must persist for about 200 |js 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...

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 65 V, 270 V and 350 V. 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 65 V, 270 V and 350 V. Figure 5: Output Current / Output Power derating curve as a function...

Technical Figures Figure 7: Turn-on transient at full resistive load and zero output capacitance initiated by ENA1. Input voltage pre-applied. Ch 1: Vout (2 V/div). Ch 2: ENA1 (5 V/div). Figure 8: Turn-on transient at full resistive load and 3mF output capacitance initiated by ENA1. Input voltage pre-applied. Ch 1: Vout (2 V/div). Ch 2: ENA1 (5 V/div). Figure 9: Turn-on transient at full resistive load and zero output capacitance initiated by ENA2. Input voltage pre-applied. Ch 1: Vout (2 V/div). Ch 2: ENA2 (5 V/div). Figure 10: Turn-on transient at full resistive load and zero output capacitance...

Technical Figures Figure 13: Output voltage response to step-change in input voltage (65 V 350 V - 65 V) in 285 μS. Load cap: 10 µF, 100 mΩ ESR tantalum cap and 1 µF ceramic cap. Ch 1: Vin (100 V/div). Ch 2: Vout (500 mV/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 (50 mA/div). Bandwidth: 20 MHz. See Figure 14. Figure 16: Output voltage ripple, Vout, at nominal input...

Output Impedance (ohms) 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. 10000 Input Impedance (ohms) 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...

Application Section 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...