DC/DC CONVERTERS 28 VOLT INPUT

www.DataSheet4U.com FEATURES • • • • • • • • • • • –40°C to + 85°C operation 19 to 40 VDC input Fully Isolated Optocoupler feedback Fixed frequency, 245 kHz typical Topology – Push-Pull Forward 50 V for up to 50 ms transient protection Inhibit/sync function Indefinite short circuit protection Remote sense on single models Up to 84% efficiency DC/DC CONVERTERS 28 VOLT INPUT SINGLE 5 12 15 HR700 SERIES 70 WATT MODELS VDC OUTPUT DUAL ±12 ±15 TRIPLE +5 & ±12 +5 & ±15 Size (max.): 3.20 x 2.46 x 0.595 inches (81.3 x 62.5 x 15.11 mm) See Section B8, case L, for dimensions. Weight: 140 grams typical Screening: Standard only. See Section B9 for screening description. DESCRIPTION HR700 Series DC/DC converters offer up to 70 watts of power from single, dual, or triple outputs in one package. The converters combine the small size and high reliability of hybrid-based components, the high efficiency of switching regulators, and the isolation, regulation, and low noise characteristics of linear regulators. provided by detecting peak primary switching current on a cycle basis and limiting it to approximately 130% of the full load input current. This method results in quick and positive current limiting under short circuit conditions. HR700 Series DC/DC converters are designed to provide full power operation over the input voltage range of 19 to 40 VDC. Operation below an input of 19 volts is possible with derated output power. Outputs are available as 5, 12, and 15 VDC single, dual and triple outputs. The converters typically provide greater than 80% efficiency over the entire input range. Line regulation is typically within 0.1% and load regulation within 0.2%. SMALL SIZE The HR700 converters are manufactured using techniques that provide very small size and low profile components. Each converter uses less than eight square inches of board areas and is 0.595 inches high or less. The overall power density is 20 watts per cubic inch. LOW NOISE The HR700 Series converters offer low noise on both the input and output lines. A two section, four pole, LC input filter is included to provide very low reflected line ripple current. Output ripple is maintained at less than 50 mV p-p for single and dual models and 85 mV p-p for triple output models. HIGH RELIABILITY Assembled using thick-film technology, the HR700 parts use the same manufacturing procedures and quality controls that we apply to converters designed for commercial airliners, the space shuttle, advanced fighter aircraft, and other high reliability applications. The steel cases are hermetically sealed in a dry nitrogen environment and are guaranteed a maximum leak rate of less than 10-3 atmcc/sec. All devices are 100% electrically tested. INHIBIT/SYNC FEATURE An inhibit/sync pin is standard on all models of the HR700 Series converters. The pin serves as both an output inhibit and as a synchronization input. In the inhibit mode an open collector TTL compatible low (<0.8 V) will disable internal switching thereby inhibiting the unit’s output. Inhibiting in this manner results in an extremely low quiescent current. HIGH PERFORMANCE The HR700 series parts are high efficiency, low noise, pulse-width modulated converters which use a quasi-square wave forward converter design with a nominal switching frequency of 245 kHz. Isolation between input an output is provided with a transformer in the forward power loop and a wide band, temperature insensitive, optical link in the feedback control loop. Short circuit protection is B4-33 www.DataSheet4U.com HR700 SERIES 70 WATT ABSOLUTE MAXIMUM RATINGS DC/DC CONVERTERS SYNC AND INHIBIT Sync In (245 to 370 kHz.) • Duty cycle 70% min, 98% max. • Logic low 0.8V max • Logic high 4.5 V min • Referenced to input common • If sync is not used, leave unconnected Inhibit TTL Open Collector • Logic low (output disabled) Inhibit pin current 1 mA max • Referenced to input common • Logic high (output enabled) V = ≥ 4.5V TYPICAL CHARACTERISTICS Output Voltage Temperature Coefficient • 150 ppm/°C, typical Input to Output Capacitance • 160 pF, typical Isolation • 100 megohm minimum at 500 V Conversion Frequency • Free run mode 245 kHz, typical Inhibit Pin Voltage (unit enabled) • 4.5 to 5.5 V Output Power • 60 to 70 watts depending on model Lead Soldering Temperature (10 sec per lead) • 300°C Storage Temperature Range (Case) • –55°C to +125°C RECOMMENDED OPERATING CONDITIONS Input Voltage Range • 19 to 40 VDC continuous (see Derating) Case Operating Temperature (Tc) • –40°C to +85°C full power DERATING OUTPUT POWER/CURRENT AND INPUT VOLTAGE Temperatures are referenced to the temperature at the converter’s baseplate • Linearly derate output power/current from 100% at 85°C to 0% at 125°C. • Above 105°C linearly derate steady state input voltage to 33 volts at 125°C. • Indefinite short circuit protection is not guaranteed above 85°C case. • Operation below an input voltage of 19 volts, including operation in MILSTD-704E emergency power conditions, is possible with derated output power. See Figures 10 and 11. Electrical Characteristics: 25°C Tc, 28 VDC Vin, 100% load, free run, unless otherwise specified. SINGLE OUTPUTS PARAMETER OUTPUT VOLTAGE OUTPUT CURRENT OUTPUT POWER OUTPUT RIPPLE LINE REGULATION LOAD REGULATION INPUT VOLTAGE INPUT CURRENT INPUT REFL. RIPPLE EFFICIENCY STARTUP DELAY CONDITION FULL LOAD VIN = 19 TO 40 Tc = –55°C TO +85°C FULL LOAD BW ≤ 2 MHz VIN = 19 TO 40 NO LOAD TO FULL HR701-2805 MIN 4.90 — — — — — 19 NO LOAD INHIBITED FULL LOAD BW ≤10 MHz WITH LOW IMPEDANCE SOURCE — — — 77 — TYP 5.00 — — 30 10 10 28 75 30 10 80 5 MAX 5.10 12.00 60 100 30 30 40 100 35 50 — 10 HR701-2812 MIN TYP MAX HR701-2815 MIN. TYP MAX UNITS VDC A W mV p-p mV mV VDC mA mA p-p % ms 11.75 12.00 12.25 — — — — — 19 — — — 80 — — — 30 10 10 28 70 30 10 83 8 5.83 70 100 30 30 40 100 35 50 — 10 14.75 15.00 15.25 — — — — — 19 — — — 80 — — — 30 10 10 28 70 30 10 83 8 4.67 70 100 30 30 40 100 35 50 — 10 B4-34 www.DataSheet4U.com DC/DC CONVERTERS DUAL AND TRIPLE OUTPUTS PARAMETER OUTPUT VOLTAGE CONDITION FULL LOAD MAIN DUAL MAIN DUAL MIN HR702-2812 TYP MAX — — — ±11.75 ±12.00 ±12.25 — — — — — MAIN DUAL MAIN DUAL MAIN DUAL — — — — — — — 2.92 — 35 — — 30 — 10 — 25 — 5.5 — 66.5 70 — 100 — 30 — 50 HR702-2815 MIN TYP MAX HR703-28512 MIN TYP MAX MIN HR700 SERIES 70 WATT HR703-28515 TYP MAX UNITS VDC Electrical Characteristics: 25°C Tc, 28 VDC Vin, 100% load, free run, unless otherwise specified. — — — 4.90 5.05 5.15 4.90 4.95 5.10 ±14.75 ±15.00 ±15.25 ±11.50 ±11.80 ±12.10 ±15.05 ±15.30 ±15.75 — — — — — — — — — — — — 2.33 — 35 — — 30 — 10 — 25 — 4.4 — 66.5 70 — 100 — 30 — 50 — — — — — — — — — — — 4.0 1.67 20 20 — 50 50 2 100 5 480 10.0 4.2 50 50 60 100 100 25 225 30 750 — — — — — — — — — — — 4.0 1.33 20 20 — 50 50 2 100 5 300 10.0 3.33 50 50 60 100 100 25 225 30 600 OUTPUT VIN = CURRENT1, 2 19 TO 40 OUTPUT POWER1, 2 OUTPUT RIPPLE MAIN ±DUAL TOTAL FULL LOAD BW ≤ 2 MHz A W mV p-p mV mV LINE VIN = REGULATION 19 TO 40 NO LOAD LOAD3 REGULATION TO FULL DUAL CROSS4 REGULATION +PO = 3 W TO 35 W –PO = 35 W +PO = 20 W TO 50 W –PO = 50 W TO 20 W MAIN +PO = 30 W CROSS5 REGULATION DUAL +PO = 3 W TO 27 W –PO = 27 W TO 3 W MAIN +PO = 3 W TO 30 W DUAL ±PO = 15 W INPUT VOLTAGE INPUT CURRENT INPUT REFL. RIPPLE EFFICIENCY STARTUP DELAY NO LOAD INHIBITED FULL LOAD BW ≤10 MHz — — 1.5 2.0 3.0 4.0 — — 1.5 2.0 3.0 3.5 — — — — — — — — — — — — % — — — — — — — 2.3 6.0 — 2.3 5.0 % — 19 — — — 80 — — 28 75 25 15 83 15 — 40 100 35 50 — 25 — 19 — — — 80 — — 28 75 25 15 83 15 — 40 100 35 50 — 25 — 19 — — — 79 — 5.4 28 85 30 15 84 6 9.0 40 115 35 50 — 10 — 19 — — — 79 — 5.0 28 60 30 15 84 6 7.0 40 115 35 50 — 10 VDC mA mA p-p % ms Notes 1. On dual output models the maximum combined output power is 70 watts. A maximum of 95% (66.5 W) is available from any single output. 2. On triple output models the maximum combined output power is 60 watts. A maximum of 50 watts is available from a single output. 3. Balanced loads 4. Regulation effect on the negative dual output during the defined conditions. 5. Regulation effect on both dual outputs during the defined conditions. B4-35 www.DataSheet4U.com HR700 SERIES 70 WATT DC/DC CONVERTERS THERMAL MANAGEMENT HEAT SINK RECOMMENDATIONS An HR700 Series converter in still air (other than convective currents) and with no conductive cooling paths other than through electrical connections at the pins will exhibit a thermal resistance of approximately 4°C / watt. In cases where this value proves to be too high it is recommended that additional heat sinking be supplied. The simplest method of accomplishing this is to firmly attach the converter to a PCB thereby providing a conductive thermal path. Secondly it is recommended that airflow be provided over the converter. Although each situation requires a thorough thermal analysis these two measures can reduce the thermal resistance to as low as 2°C / watt. If calculations indicate further heat sinking is required it is recommended that additional thermal mass be provided either under the base plate or on top of the converter's mounting flanges or both. CALCULATING MAXIMUM AMBIENT TEMPERATURE The HR700 Series of DC/DC converters has an upper operating temperature of + 85°C at the baseplate of the case. The degree of heat sinking required to remain within this limit may be determined from Figure 1 which shows the maximum allowed internal power dissipation (PDISS vs. ambient temperature for various heat sink thermal re