PD-97823A M3GB-SERIES HYBRID - HIGH RELIABILITY RADIATION HARDENED DC-DC CONVERTER 28V Input, Single/Dual Output Description The M3GB-Series of DC-DC converters are second generation design of the legacy M3G-Series product family but with enhanced overall performance. M3GBSeries is form, fit and functional equivalent to the first generation M3G-Series. It is designed to be backward compatible to the M3G-Series with the addition of an output voltage adjustment pin for the single output models. Much the same as the original M3G-Series, these 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. 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 any 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 0.475" package constructed of an Aluminum/Silicon-Carbide (Al/SiC) base and an Alloy 48 ring frame and they weigh less than 110 grams. The package utilizes rugged ceramic feed-through copper core pins and is sealed using parallel seam welding. Manufactured in a facility fully qualified to MIL-PRF38534, these converters are fabricated utilizing DLA Land and Maritime qualified processes. For available screening options, refer to device screening table in the data sheet. M3GB Features n Total Dose > 200 kRads(Si), typically usable to > 300 kRads(Si) n SEE Hardened to LET up to 82 MeV.cm2/mg n Internal EMI filter; Converter Capable of meeting MIL-STD-461C CE03 n Low Weight, < 110 grams n Magnetically Coupled Feedback n 18V to 50V DC Input Range n Up to 40W Output Power n Single and Dual Output Models Include 3.3, 5, 5.2, 12, 15, ±5, ±7, ±12 and ±15V n High Efficiency - to 83% n -55°C to +125°C Operating Temperature Range n 100MΩ @ 100VDC Isolation n Under-Voltage Lockout n Short Circuit and Overload Protection n Remote Sense on Single Output Models n Adjustable Output Voltage for all Models n Synchronization Input and Output n External Inhibit n > 7,000,000 hour MTBF Applications n Geostationary Earth Orbit Satellites (GEO) n Deep Space Satellites / Probes n Strategic Weapons and Communication System Non-flight versions of the M3GB-Series converters are available for system development purposes. Variations in electrical specifications and screening to meet custom requirements can be accommodated. www.irf.com 1 11/10/15 M3GB-SERIES (28V Input, Single/Dual Output) Circuit Description The M3BG-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 30% over the nominal regardless of the line voltage. An internal EMI filter allows the converter to meet the conducted emissions requirements of MIL-STD-461C on the input power leads. A two-stage output filter reduces the typical output ripple to less than 20mV peak-to-peak. 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. 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 16.5 volts and will shut down when the input voltage drops below 15.3 volts. The 1.2V of hysteresis reduces the possibility of line noise interfering with the converter’s start-up and shut down. 2 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. Remote sense is provided on the single output models to compensate for voltage drops in the interconnects between the converter and the load. The output voltage of dual output models can be adjusted by a single external resistor. Design Methodology The M3GB-Series was developed using a proven conservative design methodology which includes selecting radiation tolerant and established reliability components and fully derating to the requirements of MIL-STD-1547 and MIL-STD-975 (except for the CDR type ceramic capacitors, where capacitors with 50V ratings may be used with voltage stresses of less than 10V). Careful sizing of decoupling capacitors and current limiting resistors minimizes the possibility of photo-current burn-out. Heavy derating of the radiation hardened power MOSFET virtually eliminates the possibility of SEGR and SEB. A magnetic feedback circuit is utilized instead of optocouplers 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 M3GB-SERIES (28V Input, Single/Dual Output) Specifications Absolute Maximum Ratings Input voltage range Recommended Operating Conditions -0.5VDC to +80VDC Internally limited Output power 3 Input voltage range +18VDC to +60VDC 1 +18VDC to +45VDC Lead temperature +300°C for 10 seconds Input voltage range Output power Operating temperature -55°C to +135°C Operating temperature 2 -55°C to +125°C Storage temperature -55°C to +135°C Operating temperature 1 -55°C to +70°C 0 to Max. Rated 1 Meets derating per MIL-STD-975 For operation at +125°C see table Note 13 3 Max voltage is 75V for 5V models 2 Electrical Performance Characteristics Group A Subgroup Parameter Conditions -55°C ≤ TC ≤ +85°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified Input Voltage (VIN) Output Voltage (VOUT) M3GB2803R3S M3GB2805S M3GB2805R2S M3GB2812S M3GB2815S M3GB2805D M3GB2807D M3GB2812D M3GB2815D 1 1 1 1 1 1 1 1 1 IOUT = 100% rated load Note 4 2,3 2,3 2,3 2,3 2,3 2.3 2,3 2,3 2,3 M3GB2803R3S M3GB2805S M3GB2805R2S M3GB2812S M3GB2815S M3GB2805D M3GB2807D M3GB2812D M3GB2815D Output power (POUT) M3G2803R3S All Others Output current (IOUT) M3GB2803R3S M3GB2805S M3GB2805R2S M3GB2812S M3GB2815S M3GB2805D M3GB2807D M3GB2812D M3GB2815D Unit Min Nom Max 18 28 50 3.31 5.01 5.21 12.00 15.00 ±5.01 ±7.00 ±12.00 ±15.00 3.33 5.03 5.23 12.05 15.06 ±5.03 ±7.03 ±12.05 ±15.06 3.29 4.99 5.19 11.95 14.94 ±4.99 ±6.97 ±11.95 ±14.94 3.26 4.95 5.15 11.88 14.85 ±4.95 ±6.93 ±11.88 ±14.85 3.34 5.05 5.25 12.12 15.15 ±5.05 ±7.07 ±12.12 ±15.15 V V 1,2,3 VIN = 18, 28, 50 Volts, Note 2 0 0 30 40 1,2,3 VIN = 18, 28, 50 Volts, Note 2 0 0 0 0 0 0 0 0 0 9.10 8.00 7.70 3.34 2.67 6.40 4.57 2.67 2.14 -10 -20 10 20 mV -0.5 0.5 % Either Output, Note 3 Either Output, Note 3 Either Output, Note 3 Either Output, Note 3 1,2,3 Line regulation (VRLINE) Single Dual Load regulation (VRLOAD) IOUT = 100% rated load Note 4 Limits 1,2,3 VIN = 18, 28, 50 Volts IOUT = 0, 50%, 100% rated, Note 4 IOUT = 0, 50%, 100% rated, Note 4 VIN = 18, 28, 50 Volts W A For Notes to Specifications, refer to page 5 www.irf.com 3 M3GB-SERIES (28V Input, Single/Dual Output) Electrical Performance Characteristics Parameter Cross regulation (VRCROSS) M3GB2805D M3GB2807D M3GB2812D M3GB2815D Group A Subgroup (continued) Conditions -55°C ≤ TC ≤ +85°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified 1,2,3 Duals only, Note 5 VIN = 18, 28, 50 Volts Input current (IIN) 1,2,3 Switching frequency (FS) 1,2,3 Sync. Input (Pin 4) open 1,2,3 IOUT = 100% rated load Notes 4, 6 Output ripple (VRIP) M3GB2803R3S M3GB2805S M3GB2805R2S M3GB2812S M3GB2815S M3GB2805D M3GB2807D M3GB2812D M3GB2815D Efficiency (EFF) M3GB2803R3S M3GB2805S M3GB2805R2S M3GB2812S M3GB2815S M3GB2805D M3GB2807D M3GB2812D M3GB2815D 1,2,3 5.0 4.0 2.0 2.0 -5.0 -4.0 -2.0 -2.0 2.0 5.0 500 525 kHz 15 20 25 25 25 20 25 30 30 35 50 50 60 80 50 55 60 60 mV p-p Ext. Clock on Sync. Input (Pin 4) Note 1 VOUT = 90% of Nominal, Note 4 1,2,3 Short Circuit, Overload, Note 8 Output response to step load changes (VTLD) 4,5,6 Recovery time, step load changes (TTLD) 4,5,6 Half Load to/from Full Load, Notes 4, 9 Half Load to/from Full Load, Notes 4, 9,10 22V to/from 34V IOUT = 100% rated load, Notes 1,4,11 Output response to step line changes (VTLN) Recovery time, step line changes (TTLN) 475 72 78 78 77 77 78 78 77 78 75 80 80 80 81 80 80 81 82 3.0 450 4.0 -0.5 40 20 118 No Load, Full Load Notes 4,12 125 12 -300 50 -200 22V to/from 34V IOUT = 100% rated load, Notes 1,4,10,11 4,5,6 % Pin 3 shorted to Pin 2 -0.5 1,2,3 Max 80 Power dissipation, load fault (PD) Turn-on Response Overshoot (VOS) Turn-on Delay (TDLY) Nom 50 Note 1 Synchronization Input frequency range pulse high level pulse low level pulse transition time pulse duty cycle Current Limit Point Expressed as a percentage of full rated load current Unit Min IOUT = 0, Pin 3 open IOUT = 100% rated load Note 4 Enable/Inhibit Input open circuit voltage drive current (sink) voltage range Limits 50 1.0 mA % 5.0 100 50 V µA V 600 10 0.5 80 kHz V V V/µs % 130 % 18 W 300 mVpk 200 µs 200 mV pk 200 µs 2.0 5.0 % ms For Notes to Specifications, refer to page 5 4 www.irf.com M3GB-SERIES (28V Input, Single/Dual Output) Electrical Performance Characteristics Parameter Group A Subgroup Capacitive Load (CL) M3GB2803R3S M3GB2805S M3GB2805R2S M3GB2812S M3GB2815S M3GB2805D M3GB2807D M3GB2812D M3GB2815D Conditions -55°C ≤ TC ≤ +85°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified Limits Unit Min Nom Each output on duals IOUT = 100% rated load DC to 50kHz, Notes 1, 4 1 Input to Output or Any Pin to Case except Pin 6, test @ 100VDC 40 50 MΩ 110 MIL-HDBK-217F2, SF, 35°C µF dB 100 Device Weight MTBF Max 2200 1000 1000 180 120 500 300 90 60 IOUT = 100% rated load No effect on DC performance Notes 1, 4, 7 Line Rejection Isolation (continued) 6 7.0 x 10 g Hrs Notes: Electrical Performance Characteristics Table 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Parameter is guaranteed to the limits specified in table by design, but not tested. Limits apply to the operating range specified in table, unless otherwise specified. No Group A subgroups are specified for this test. Parameter verified during line and load regulation tests. Limit represents 80% of total rated output current. To achieve rated output power, the remaining 20% of the total rated output current must be provided by the other output. Load current split equally between outputs on dual output models. Cross regulation is measured with 20% rated load on output under test while changing the load on the other output from 20% to 80% of rated. Guaranteed for a D.C. to 20MHz bandwidth. Tested using a 20kHz to 10MHz bandwidth. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance. 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. Overload power dissipation is defined as the device power dissipation with the load set such that VOUT = 90% of nominal. Load step transition time ≥ 10 µs. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1% of its steady state value. Line step transition time ≥ 100 µs. 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. For operation at temperatures between +85°C and +125°C, derate the maximum input voltage linearly from 60V to 40V and the maximum output power linearly from 100% to 75%. www.irf.com 5 M3GB-SERIES (28V Input, Single/Dual Output) Fig 1. Block Diagram - Single Output + - Fig 2. Block Diagram - Dual Output + - 6 www.irf.com M3GB-SERIES (28V Input, Single/Dual Output) Fig 3. Typical Conducted Emissions, Positive Lead Fig 4. Typical Line Rejection www.irf.com 7 M3GB-SERIES (28V Input, Single/Dual Output) Fig 5. Typical Efficiency @25°C, M3GB2805S 90 E fficiency, % 80 70 18V Input 60 28V Input 50 50V Input 40 0 10 20 30 40 50 60 70 80 90 100 P ercentage of R ated L oad, % Fig 6. Typical Efficiency @25°C, M3GB2815D 90 E fficiency, % 80 70 18V Input 60 28V Input 50V Input 50 40 0 10 20 30 40 50 60 70 80 90 100 P ercentage of rated L oad, % 8 www.irf.com M3GB-SERIES (28V Input, Single/Dual Output) Radiation Performance Characteristics Test Method Min Typ Unit 200 300 kRads(Si) MIL-PRF-883, Method 1019 Total Ionizing Dose (Gamma) Operating bias applied during exposure, Full Rated Load, VIN = 28V Dose Rate (Gamma Dot) Temporary Saturation Survival Neutron Fluence MIL-STD-883, Method 1023 Operating bias applied during exposure, 1E8 Rads(Si)/sec Full Rated Load, VIN = 28V 4E10 1E11 (Supported by Analysis) MIL-STD-883, Method 1017 8E12 1E13 2 Neutrons/cm (Supported by Analysis) Heavy Ions (LET) Single Event Effects Operating bias applied during exposure, SEU, SEL, SEGR, SEB Full Rated Load, VIN = 18V, 28V, 50V 82 2 MeVxcm /mg Application Notes: A) Attachment of the Converter. The following procedure is recommended for mounting the converter for optimum cooling and to circumvent any potential damage to the converter. Ensure that flatness of the plate where M3GB converter to be mounted is no greater than 0.003” per linear inch. It is recommended that a thermally conductive gasket is used to promote the thermal transfer and to fill any voids existing between the two surfaces. IR recommends Sil-Pad 2000 with the thickness of 0.010". The shape of the gasket should match the footprint of the converter including the mounting flanges. The gasket is available from IR. The M3GB-Series converter requires either M3 or 4-40 size screws of attachment purposes. The procedure for mounting the converter is as follows: 1. 2. 3. 4. Check the mounting surfaces and remove foreign material, burrs if any or anything that may interfere with the attachment of the converter. Place the gasket on the surface reserved for the converter and line it up with the mounting holes. Place the converter on the gasket and line both up with mounting holes. Install screws using appropriate washers and tighten by hand (~ 4 in·oz) in the sequence shown below. 5. Tighten the screws with an appropriate torque driver. Torque the screws up to 6 in·lb in the sequence shown above. www.irf.com 9 M3GB-SERIES (28V Input, Single/Dual Output) B) Output Voltage Adjustment. Single Output: To adjust the output voltage of the single output models, a resistor (RADJ) is connected between the Adjust pin (Pin 8) and either the positive or negative remote sense pins, depending on whether the output voltage is to be adjusted higher or lower than the nominal set-point. This allows the outputs to be reliably adjusted by approximately +10% to -20% of the nominal output voltage. Refer to Fig. 7 and use equations provided to calculate the required resistance (RADJ). Fig 7. Configuration for Adjusting Single Output Voltage For all Single Output Models, to adjust the output voltages higher: RADJ = 10 x (VNOM – 2.5) VOUT - VNOM - 50 Where: RADJ is in kOhms RADJ is connected to the -Out pin and VNOM < VOUT < 1.1VNOM (Fig. 7, Note 2) VNOM is the nominal output voltage with the Adjust Pin left open VOUT is the desired output voltage For all Single Output Models, to adjust the output voltages lower: RADJ = 4 x (VNOM – 2.5) x ( VOUT – 2.5) - 50 VNOM - VOUT Where: RADJ is in kOhms RADJ is connected to the +Out pin and 0.8VNOM < VOUT < VNOM (Fig. 7, Note 1) VNOM is the nominal output voltage with the Adjust Pin left open VOUT is the desired output voltage 10 www.irf.com M3GB-SERIES (28V Input, Single/Dual Output) Dual Output: The dual output voltage of the dual output models, a resistor (RADJ) is connected between the Adjust pin (Pin 8) and either output. This allows the outputs to be reliably adjusted by approximately +10% to -20% of the nominal output voltage. Refer to Fig. 8 and use equations provided to calculate the required resistance (RADJ). Fig. 8. Configuration for Adjusting Dual Output Voltage For all Dual Output Models, to adjust the output voltages higher: RADJ = 10 x (VNOM – 1.25) VOUT - VNOM - 75 Where: RADJ is in kOhms RADJ is connected to the -Out pin and VNOM < VOUT < 1.1VNOM (Fig. 8, Note 2) VNOM is the nominal magnitude of the output voltages with the Adjust pin left open VOUT is the desired magnitude of the output voltages For all Dual Output Models, to adjust the output voltages lower: RADJ = 8 x (VNOM – 1.25) x ( VOUT – 1.25) VNOM - VOUT - 75 Where: RADJ is in kOhms RADJ is connected to the +Out pin and 0.8VNOM < VOUT < VNOM (Fig. 8, Note 1) VNOM is the nominal magnitude of the output voltages with the Adjust pin left open VOUT is the desired magnitude of the output voltages www.irf.com 11 M3GB-SERIES (28V Input, Single/Dual Output) Mechanical Diagram 3.055 MAX. 0.500 0.080 Max. 2.00 R0.0625 4 places 0.30 0.50 0.20 13 1 12 2 11 10 0.60 9 3 8 4 7 5 6 2.055 MAX. 2.30 0.200 Typ. Noncum. 1.400 Ref. 2.500 Pin Ø0.040 0.45 1.10 0.260 FLANGE DETAIL 3.50 Ref. R0 0.25 0.25 62 .0 5 0.14 0.475 MAX. 0.40 Tolerance : .XX .XXX ±0.01 ±0.005 Pin Designation (Single/Dual) 12 Pin # Designation Pin # Designation 1 + Input 8 Adjust 2 Input Return 9 - Sense / NC 3 Inhibit 10 + Sense / NC 4 Sync. Input 11 NC / - Output 5 Sync. Output 12 Output Return 6 7 Case Ground NC 13 + Output www.irf.com M3GB-SERIES (28V Input, Single/Dual Output) Device Screening Requirement MIL-STD-883 Method Temperature Range No Suffix d CK d EM -55°C to +85°C -55°C to +85°C -55°C to +85°C Element Evaluation MIL-PRF-38534 Class K Class K N/A Non-Destructive Bond Pull 2023 Yes Yes N/A Internal Visual 2017 Yes Yes c Temperature Cycle 1010 Cond C Cond C Cond C Constant Acceleration 2001, Y1 Axis 3000 Gs 3000 Gs 3000 Gs PIND 2020 Cond A Cond A N/A 320 hrs @ 125°C 320 hrs @ 125°C 48 hrs @ 125°C Burn-In 1015 ( 2 x 160 hrs ) ( 2 x 160 hrs ) Final Electrical MIL-PRF-38534 -55°C, +25°C, -55°C, +25°C, -55°C, +25°C, ( Group A ) & Specification +85°C +85°C +85°C PDA MIL-PRF-38534 2% 2% N/A Seal, Fine and Gross 1014 Cond A, C Cond A, C Cond A Radiographic 2012 Yes Yes N/A External Visual 2009 Yes Yes c Notes: c d Best commercial practice. CK is a DLA Land and Maritime (formerly DSCC) part marking used to designate a Class K compliant hybrid. The CK marking does not indicate the hybrid is radiation certified. No Suffix is a radiation rated device but not available as a DLA Land and Maritime qualified SMD per MIL-PRF-38534. Part Numbering M3GB 28 05 S /XX X Model Nominal Input Voltage 28 = 28V Output Voltage 03R3 = 3.3V, 05 = 5V 05R2 = 5.2V, 12 = 12V 15 = 15V Lead Finish for CK only C = Gold Plated A = Solder Dipped Blank for No Suffix and EM Lead Finish for No Suffix = Gold Plated Lead Finish for EM is Gold Plated or Solder Dipped depending on availability Screening Level (Please refer to Screening Table) No Suffix, CK, EM Output S = Single D = Dual WORLD HEADQUARTERS: 101 N, Sepulveda Blvd, El Segundo, California 90245, Tel: (310) 252-7105 IR SAN JOSE: 2520 Junction Avenue, San Jose, California 95134, Tel: (408) 434-5000 Visit us at www.irf.com for sales contact information. Data and specifications subject to change without notice. 11/2015 www.irf.com 13