PD - 94559A G-SERIES ADVANCED ANALOG HIGH RELIABILITY RADIATION HARDENED DC/DC CONVERTER 50V Input, Triple Output Description The G-Series of DC/DC converters are radiation hardened, high reliability converters designed for extended operation in hostile environments. Their small size and low weight make them ideal for applications such as geostationary earth orbit satellites and deep space probes. They exhibit a high tolerance to total ionizing dose, single event effects and environmental stresses such as temperature extremes, mechanical shock, and vibration. All components are fully derated to meet the requirements of MIL-STD-975, MIL-STD-1547 and GSFC PPL-21 Appendix B. Extensive documentation including Radiation Susceptibility, Thermal, Stress, Worst Case, Failure Modes and Effects analyses and MTBF are available for customer review and included with each order. The converters incorporate a fixed frequency single ended forward topology with magnetic feedback and an internal EMI filter that utilizes multilayer ceramic capacitors that are subjected to extensive lot screening for optimum reliability. These converters are capable of meeting the conducted emissions and conducted susceptibility requirements of MIL-STD-461C without additional components. External inhibit and synchronization input and output allow these converters to be easily incorporated into larger power systems. They are enclosed in a hermetic 3" x 2" x 0.445" package constructed of an Aluminum/Silicon-Carbide (Al/SiC) base and an Alloy 48 ring frame and they weigh less than 80 grams. The package utilizes rugged ceramic feed-through copper core pins and is sealed using parallel seam welding. Full environmental screening includes temperature cycling, constant acceleration, fine and gross leak, particle impact noise detection (PIND), radiographic and 320 hours burn-in. Non-flight versions of the G-Series converters are available for system development purposes. Variations in www.irf.com Features n Total Dose > 200K Rad(Si), typically usable to > 1M Rad(Si) n n n n n n n n n n n n n n n n n SEE > 82 MeV.cm2/mg Low Weight, < 90 grams Low Input & Output Noise Magnetically Coupled Feedback 38V to 60V DC Input Range Up to 40W Output Power Triple Output Models Include +5V and ±12V or ±15V Main Output Isolated from Dual Outputs High Efficiency - to 80% -55°C to +125°C Operating Temperature Range 100MΩ @ 500VDC Isolation Under-Voltage Lockout Synchronization Input and Output Short Circuit and Overload Protection Output Over Voltage Limiter External Inhibit 5,000,000 Hour MTBF Applications n n n Geostationary Earth Orbit Satellites (GEO) Deep Space Satellites / Probes Strategic Weapons and Communication Systems electrical specifications and screening to meet custom requirements can be accommodated. 1 10/24/02 G-SERIES Circuit Description The G-Series converters utilize a single-ended forward topology with resonant reset. The nominal switching frequency is 500kHz. Electrical isolation and tight output regulation are achieved through the use of a magnetically coupled feedback. Voltage feed-forward with duty factor limiting provides high line rejection and protection against output over voltage in the event of an internal control loop failure. This mechanism limits the maximum output voltage to approximately 20% over the nominal regardless of the line voltage. An internal EMI filter allows the converter to meet the conducted emissions requirements of MIL-STD461C on the input power leads. A two-stage output filter reduces the typical output ripple to less than 20mV peak-to-peak. The main ( +5 volt ) output is regulated by the control loop and typically exhibits better than 1% regulation. The auxiliary ( ±12 volt or ±15 volt ) outputs are maintained through tight coupling in the power transformer and main output filter inductor and typically exhibit better than 5% regulation. The main output and auxiliary outputs are isolated from each other. Output current is limited under any load fault condition to approximately 125% of rated. An overload condition causes the converter output to behave like a constant current source with the output voltage dropping below nominal. The converter will resume normal operation when the load current is reduced below the current limit point. This protects the converter from both overload and short circuit conditions. The current limit point exhibits a slightly negative temperature coefficient to reduce the possibility of thermal runaway. 2 An under-voltage lockout circuit prohibits the converter from operating when the line voltage is too low to maintain the output voltage. The converter will not start until the line voltage rises to approximately 34.5 volts and will shut down when the input voltage drops below 35.5 volts. The one volt of hysteresis reduces the possibility of line noise interfering with the converter’s start-up and shut down. An external inhibit port is provided to control converter operation. The nominal threshold relative to the input return (pin 2) is 1.4V. If 2.0 volts or greater are applied to the Inhibit pin (pin 3) then the converter will operate normally. A voltage of 0.8V or less will cause the converter to shut-down. The pin may be left open for normal operation and has a nominal open circuit voltage of 4.0V. Synchronization input and output allow multiple converters to operate at a common switching frequency. Converters can be synchronized to one another or to an externally provided clock. This can be used to eliminate beat frequency noise or to avoid creating noise at certain frequencies for sensitive systems. Design Methodology The G-Series was developed using a proven conservative design methodology that includes selecting radiation tolerant and established reliability components and fully derating to the requirements of MIL-STD-975 and MIL-STD-1547. Careful sizing of decoupling capacitors and current limiting resistors minimizes the possibility of photo-current burnout. Heavy derating of the radiation hardened power MOSFET virtually eliminates the possibility of SEGR and SEB. A magnetic feedback circuit is utilized instead of opto-couplers to minimize temperature, radiation and aging sensitivity. PSPICE and RadSPICE were used extensively to predict and optimize circuit performance for both beginning and end-of-life. Thorough design analyses include Radiation Susceptibility (TREE ), Worst Case, Stress, Thermal, Failure Modes and Effects (FMEA) and Reliability (MTBF). www.irf.com G-SERIES Absolute Maximum Ratings Recommended Operating Conditions Input voltage range -0.5Vdc to +80Vdc Output power Internally limited Lead temperature +300°C for 10 seconds Operating temperature - -55°C to +135°C Storage temperature -55°C to +135°C Input voltage rangeOutput power Operating temperature- 38Vdc to +60Vdc 0 to Max. Rated -55°C to +125°C Electrical Performance Characteristics Parameter Group A Subgroup Input Voltage Conditions -55°C ≤ TC ≤ +85°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified Unit Limits Min Nom Max 1, 2, 3 Note 2 38 50 60 V (main) 5012T (aux.) 5015T (aux.) 1 IOUT = 100% rated load, Note 5 4.98 ±11.50 ±14.60 5.00 ±11.80 ±14.90 5.02 ±12.10 ±15.20 V V V (main) 5012T (aux.) 5015T (aux.) 2, 3 IOUT = 100% rated load, Note 5 4.93 ±11.30 ±14.40 5.07 ±12.30 ±15.40 V V V 1, 2, 3 VIN = 38, 50, 60 Volts, Note 2 0 40 W (main) 5012T (aux.) 5015T (aux.) 1, 2, 3 VIN = 38, 50, 60 Volts, Notes 2,3,4,5 400 ±83 ±67 4000 ±833 ±667 mA mA mA (main) 5012T (aux.) 5015T (aux.) 1, 2, 3 VIN = 38, 50, 60 Volts IOUT = 10, 50%, 100% rated Note 5 -10 -120 -150 10 120 150 mV mV mV (main) 5012T (aux.) 5015T (aux.) 1, 2, 3 IOUT = 10%, 50%, 100% rated VIN = 38, 50, 60 Volts Notes 5,13 -50 -400 -500 50 400 500 mV mV mV 1, 2, 3 VIN = 38, 50, 60 Volts IOUT = 2.5A to 1A and 2.5 to 4A on main output and ±half rated on aux. outputs -3.5 -3.0 3.5 3.0 % % Output Voltage ( Vout ) Output power ( POUT ) Output current ( IOUT ) Line regulation ( VRLINE ) Load regulation ( VRLOAD ) Cross regulation ( VRCROSS ) Main (5012T aux.) (5015T aux.) For Notes to Specifications, refer to page 5 www.irf.com 3 G-SERIES Electrical Performance Characteristics Parameter ( continued ) Conditions -55°C ≤ TC ≤ +125°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified Group A Subgroup Limits Min Nom Max Unit Total regulation ( VR ) (main) 5012T (aux.) 5015T (aux.) Input current ( IIN ) 5.10 ±13.00 ±16.50 1, 2, 3 All conditions of Line, Load, and Cross Regulation, and Temperature 4.90 ±11.00 ±13.50 1, 2, 3 IOUT = 0, Pin 3 open 80 Pin 3 shorted to pin 2 5 V V V mA Output ripple ( VRIP ) 25 30 30 50 60 75 mV p-p mV p-p mV p-p 450 500 550 KHz IOUT = 100% rated load Note 5 75 79 Note 1 3.0 1, 2, 3 VIN = 38, 50, 60 Volts IOUT = 100% rated load, Notes 5, 6 Switching frequency ( FS ) 1, 2, 3 Sync. Input (Pin 4) open Efficiency ( Eff) 1, 2, 3 1,2,3 (main) 5012T (aux.) 5015T (aux.) % Inhibit Input open circuit voltage drive current ( sink ) voltage range Synchronization Input frequency range pulse high level pulse low level pulse transition time pulse duty cycle -0.5 1, 2, 3 Ext. Clock on Sync. Input (Pin 4) Note 1 450 4.0 -0.5 40 20 5.0 100 50 V µA V 600 10.0 0.5 80 Khz V V V/µS % Current Limit Point Expressed as a percentage of full rated output power 1, 2, 3 Vout = 90% of Nominal, Note 5 135 % Power dissipation, load fault (PD) 1, 2, 3 Short Circuit, Overload, Note 8 20 W Output response to step load changes (VTLD) 4, 5, 6 Half Load to/from Full Load, Notes 5,9 300 mV pk 4, 5, 6 Half Load to/from Full Load, Note 5,9,10 100 µS Output response to step line changes (VTLN) 4, 5, 6 18V to/from 50V IOUT = 100% rated load, Notes 1,5,11 300 mV pk Recovery time, step line changes (TTLN) 4, 5, 6 18V to/from 50V IOUT = 100% rated load, Notes 1,5,10,11 100 µS Recovery time, step load changes (TTLD) -300 -300 For Notes to Specifications, refer to page 5 4 www.irf.com G-SERIES Electrical Performance Characteristics Parameter Group A Subgroup ( continued ) Conditions -55°C ≤ TC ≤ +125°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified Limits Min Nom Max Unit 500 750 5 mV mV mS 1000 200 µF Turn-on Response Overshoot (VOS) (main) (aux.) Turn-on Delay (TDLY) 4, 5, 6 No Load, Full Load Notes 5,12 1 Capacitive Load (CL) 1 IOUT = 100% rated load, No effect on DC performance, Notes 1, 5, 7 Line Rejection 1 IOUT = 100% rated load DC to 50KHz, Notes 1, 5 40 Isolation 1 Input to Output or Any Pin to Case except pin 10, test @ 500VDC 100 (main) (Each aux. output) Device Weight MTBF dB 60 MΩ 90 MIL-HDBK-217F2, SF, 35ºC 5 x 106 grams Hours Table I. Electrical Performance Characteristics - notes 1. Parameter is tested as part of design characterization or after design changes. Thereafter, parameter shall be guaranteed to the limits specified. 2. Parameter verified during line and load regulation tests. 3. Although operation with no load is permissible, light loading on the main (+5 volt) output may cause the output voltage of the auxiliary outputs(±12 volt or ±15 volt) to drop out of regulation. It is therefore recommended that at least 200 mA or 20 percent of the total output power, whichever is greater, be taken from the main (+5 volt) output. 4. Although operation with no load is permissible, heavy loading on the main (+5 volt) output may cause the output voltage of the auxiliary outputs(±12 volt or ±15 volt) to rise out of regulation. It is therefore recommended that at least 50 mA or 20 percent of the total output power, whichever is greater, be taken from the auxiliary (±12 volt or ±15 volt) outputs. 5. Unless otherwise specified, “Rated” load is 20W on the main (+5 volt) output and 10 watts each on the auxiliary (±12 volt or ±15 volt) outputs. Load currents of up to 5A and ±1A on the main and auxiliary outputs respectively are acceptable as long as the total output power does not to exceed 40 watts. 6. Guaranteed for a D.C. to 20MHz bandwidth. Tested using a 20KHz to 10MHz bandwidth. 7. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance. 8. A capacitive load in excess of the maximum limit may interfere with the proper operation of the converter’s overload protection, causing erratic behavior during turn-on. 9. Overload power dissipation is defined as the device power dissipation with the load set such that VOUT = 90% of nominal. 10. Load step transition time ≤10 mSec. 11. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1% of its steady state value. 12. Line step transition time ≤100 mSec. 13. Turn-on delay time from either a step application of input power or a logic low to a logic high transition on the inhibit pin (pin 3) to the point where VOUT = 90% of nominal. 14. Load is varied for output under test while the remaining outputs are loaded at 50% of rated. Regulation relative to output voltage at 50% rated load. www.irf.com 5 G-SERIES Radiation Performance Characteristics Test Total Ionizing Dose (Gamma) Dose Rate (Gamma Dot) Temporary Saturation Survival Neutron Fluence Conditions Min Typ Highest Level Tested Unit MIL-STD-883, Method 1019 Operating bias applied during exposure, Full Rated Load, VIN = 28V 200 1000 2000 KRads (Si) MIL-STD-883, Method 1023 Operating bias applied during exposure, Full Rated Load, VIN = 28V 1E8 4E10 1E11 MIL-STD-883, Method 1017 8E12 1E13 Rads 7E10 Rads (Si)/sec (Si)/sec 5.4E13 Neutrons /cm2 Single Event Effects SEU, SEL, SEGR, SEB Heavy ions (LET) Operating bias applied during exposure, Full Rated Load, VIN = 28V >82 82 MeV•cm2 /mg Device Screening Test Inspection Method Condition Element Evaluation MIL-PRF-38534 Space Requirements Nondestructive Bond Pull MIL-STD-883, Method 2023 Internal Visual MIL-STD-883, Method 2017 Temperature Cycling MIL-STD-883, Method 1010 C Constant Acceleration MIL-STD-883, Method 2001 A, Y1 axis only PIND MIL-STD-883, Method 2020 A Electrical In accordance with device specification Burn-in MIL-STD-883, Method 1015 Final Electrical ( Group A ) In accordance with device specification Seal MIL-STD-883, Method 1014 A1 C Fine Leak Gross Leak Radiographic MIL-STD-883, Method 2012 External Visual MIL-STD-883, Method 2009 6 320 Hours www.irf.com G-SERIES Block Diagram - Triple Output Vin 1 EMI FILTER +10.5V INHIBIT 3 UNDER VOLTAGE LOCKOUT & INHIBIT BIAS SUPPLY 13 +AUX. OUTPUT 12 AUX. RETURN 11 -AUX. OUTPUT 7 +MAIN 6 MAIN RETURN 10 CASE GROUND +5V SHORT CIRCUIT & OVERLOAD LEVEL TRANSLATOR & FET DRIVE RETURN 2 + +5V +5V EA - REF SYNC. 4 INPUT + OSCILLATOR SYNC. 5 OUTPUT PWM - RAMP GENERATOR SAMPLE & HOLD FEEDBACK TRIGGER www.irf.com 7 G-SERIES ±12V Load Regulation vs 5V Load 14 13.5 ±12V Magnitudes ( Volts ) 13 12.5 12 5V load = 4A 5V load = 2A 11.5 5V load = 0.4A 11 10.5 10 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 ±12V Load Current ( Amps each ) 0.8 0.9 1 ±15V Load Regulation vs 5V Load 18 17.5 ±15V Magnitudes ( Volts ) 17 16.5 16 15.5 15 5V load = 4A 14.5 5V load = 2A 14 5V load = 0.4A 13.5 13 0 8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 ±15V Load Current ( Amps each ) 0.8 0.9 1 www.irf.com G-SERIES Mechanical Diagram 3.00 0.500 0.080 Max. 2.000 R0.0625 4 places 0.300 0.500 0.200 13 1 12 2 11 10 0.600 9 3 8 4 7 5 6 2.000 2.300 2.500 1.400 Ref. 0.200 Typ. Non-cum. Pin Ø0.040 0.450 1.100 0.260 3.50 Ref. 0.25 Tolerance : .XX ±0.01 .XXX ±0.005 0.445 Max Pin Designation (Triple) Pin Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Signal +V Input Input Return Inhibit Sync. Input Sync. Output Main Return +Main Output Pin Pin 8 Pin 9 Pin 10 Pin 11 Pin 12 Pin 13 Signal NC NC Case Ground -Aux. Output Aux. Output Return +Aux. Output Part Numbering M 3G 50 0515 T M odel In p u t V o lta g e 5 0 = 5 0 V N o m in a l O u tp u ts T = T rip le O u tp u t V o lta g e 0 5 1 2 = 5 V , ±1 2 V 0 5 1 5 = 5 V , ±1 5 V WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, Tel: (310) 322 3331 ADVANCED ANALOG: 2270 Martin Av., Santa Clara, California 95050, Tel: (408) 727-0500 Visit us at www.irf.com for sales contact information. Data and specifications subject to change without notice. 10/02 www.irf.com 9