PD-96964A LS-SERIES HYBRID - HIGH RELIABILITY RADIATION HARDENED DC/DC CONVERTER 28V Input, Single/Dual Output Description The LS-Series of DC/DC converters are, high reliability devices designed for hostile radiation hardened environments. The LS-Series provide up to 30 watts output power, small size, low weight, integrated EMI filtering and a high tolerance to environmental stresses such as radiation, temperature extremes, mechanical shock, and vibration. All components are fully de-rated to meet the requirements of MIL-STD-975. Extensive documentation including, thermal analysis, stress analysis and reliability predictions are available. The LS-Series of converters incorporate a fixed frequency single forward topology with magnetic feedback and an internal EMI filter. These converters are capable of meeting the conducted emissions requirements of MIL-STD-461C without any additional components. All models include an external inhibit port and have an adjustable output voltage. They are enclosed in a hermetic 1.5" x 2.3" x 0.425" steel package and weigh less than 80 grams. The package utilizes rugged ceramic feed-through copper core pins and is sealed using parallel seam welding. The LS-Series of DC/DC converters provide same mechanical outline, power ratings, for backward pin compatibility, to their lower radiation tolerant counterpart M3L and Military series ATS DC/DC converters. The common platform design allows for similarity between military and space system architectures. For higher output power applications the HM, M3H and M3G-Series of DC/DC converters are recommended. Manufactured in a facility fully qualified to MIL-PRF38534, these converters are fabricated utilizing DSCC qualified processes. For available screening options, refer to device screening table in the data sheet. LS Features n 18 to 40V DC Input Range n Total Ionization Dose > 100K Rad(Si) n SEE Hardened to LET (Heavy Ions) up to 2 82 MeV•cm /mg (SEU, SEL, SEGB, SEGR) n Internal EMI filter; Converter Capable of meeting MIL-STD-461C CE03 n Low Weight, < 80 grams n Magnetically Coupled Feedback n Up to 30W Output Power n Single and Dual Output Models Include 1.5, 2.5, 3.3, 5, 12, 15, ±5, ±12 and ±15V n High Efficiency - to 83% n 100MΩ @ 500VDC Isolation n Under-Voltage Protection n Short Circuit and Overload Protection n Adjustable Output Voltage n External Inhibit n > 4,000,000 Hour MTBF (SF) n Standard Microcircuit Drawings Available Applications n n n n n Geo Synchronous Satellite Low Earth Orbit Deep Space Probe Communication and Display Systems Payload and Experiment LVPS Variations in electrical specifications and screening to meet custom requirements can be accommodated. www.irf.com 1 08/11/06 LS-SERIES Circuit Description The LS-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. An internal EMI filter allows the converter to meet the conducted emissions requirements of MIL-STD461C on the input power leads. Output current is limited under any load fault condition to approximately 125% of rated. An overload condition causes the converter output voltage to drop 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 external inhibit port is provided to control converter operation. The converter’s operation is inhibited when this pin is pulled low. It is intended to be driven by an open collector logic device. The pin may be left open for normal operation and has a nominal open circuit voltage of 11V with respect to the input return (pin 2). The output voltage of all models can be adjusted using a single external resistor. Design Methodology The LS-Series was developed using a proven conservative design methodology derived from other space level designs that includes selection of established reliability components and fully derating to the requirements of MIL-STD-975. A magnetic feedback circuit is utilized instead of opto -couplers to minimize temperature, aging and radiation sensitivity. PSPICE was used extensively to predict and optimize circuit performance for both beginning and end-of-life. Thorough design analyses include stress, thermal, and reliability (MTBF). www.irf.com LS-SERIES Absolute Maximum Ratings Recommended Operating Conditions Input voltage range -0.5Vdc to +60Vdc Output power Internally limited Input voltage range Output power Lead temperature +300°C for 10 seconds Operating case temperature Operating case temperature -55°C to +125°C (Note 13) Operating case temperature2 -55°C to +135°C Storage temperature Electrical Performance Characteristics Parameter Group A Subgroup LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D Output power ( POUT ) LS2801R5S LS2802R5S LS2803R3S All Others Output current ( IOUT ) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D Conditions -55°C ≤ TC ≤ +85°C V IN = 28V DC ± 5%, CL = 0 unless otherwise specified Line regulation ( VRLINE ) Load regulation ( VRLOAD ) LS2801R5S LS2802R5S All others Cross regulation ( VRCROSS ) LS2805D LS2812D LS2815D 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 IOUT = 100% rated load Notes 4, 14 V IN = 18, 28, 40 Volts, Note 2 1,2,3 1,2,3 +4.5Vdc to +40Vdc 0 to Max. Rated -55°C to +85°C -55°C to +70°C 1. Input voltage rating is BOL. Input voltage range reduced to 20 to 40VDC for EOL. 2. Meets de-rating per MIL-STD-975 Input Voltage Output Voltage ( Vout ) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D 1 V IN = 18, 28, 40 Volts, Note 2 Either Output, Note 3 Either Output, Note 3 Either Output, Note 3 Limits Min Nom Max Unit 18 28 40 V 1.47 2.47 3.27 4.95 11.88 14.85 ±4.95 ±11.88 ±14.85 1.50 2.50 3.30 5.00 12.00 15.00 ±5.00 ±12.00 ±15.00 1.53 2.53 3.33 5.05 12.12 15.15 ±5.05 ±12.12 ±15.15 1.43 2.43 3.23 4.90 11.76 14.70 ±4.90 ±11.76 ±14.70 1.57 2.57 3.37 5.10 12.24 15.30 ±5.10 ±12.24 ±15.30 0 0 0 0 12 20 25 30 0 0 0 0 0 0 0 0 0 8.0 8.0 7.57 6.0 2.5 2.0 4.8 2.3 1.6 V V W A 1,2,3 VIN = 18, 28, 40 Volts IOUT = 0, 50%, 100% rated, Note 4 -0.5 0.5 % 1,2,3 VIN = 18, 28, 40 Volts IOUT = 0, 50%, 100% rated, Note 4 -2.0 -1.2 -1.0 2.0 1.2 1.0 % VIN = 18, 28, 40 Volts Duals only, Note 5 -5.0 -3.0 -3.0 5.0 3.0 3.0 % 1,2,3 For Notes to Electrical Performance Characteristics, refer to page 5 www.irf.com 3 LS-SERIES Electrical Performance Characteristics Parameter Input Current, no load ( IIN) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D Input current inhibited Output Ripple, ( VRIP) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D Switching frequency ( FS ) Efficiency ( EFF ) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D ( continued ) Group A Subgroup Conditions -55°C ≤ TC ≤ +85°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified 1,2,3 IOUT = 0, Pin 4 open 1,2,3 1,2,3 Enable Input ( Inhibit Function ) open circuit voltage drive current ( sink ) voltage range Unit Min Nom 8.0 35 35 35 50 70 80 80 80 80 VIN = 18, 28, 40 Volts IOUT = 100% rated load Notes 4, 6 IOUT = 100% rated load Note 4 Note 1 Current Limit Point Expressed as a percentage of full rated load current 1,2,3 Vout = 90% of Nominal, Note 4 Power dissipation, load fault (PD) 1,2,3 Short Circuit, Overload, Note 8 Output response to step load changes (VTLD) 4,5,6 Half Load to/from Full Load, Notes 4,9 Recovery time, step load changes (TTLD) 4,5,6 Half Load to/from Full Load, Note 4,9,10 Output response to step line changes (VTLN) 18V to/from 40V IOUT = 100% rated load, Notes 1,4,11 Recovery Time, step line changes (TTLN) 18V to/from 40V IOUT = 100% rated load, Notes 1,4,10,11 Max 60 60 60 70 70 70 70 100 100 Pin 4 shorted to pin 2 1,2,3 1,2,3 Limits 425 500 61 68 72 78 78 78 79 79 79 64 72 76 82 82 82 83 83 83 9.5 575 mA mA mV p-p KHz % -0.5 12 5.0 50 V mA V 105 145 % 14 W 300 mV pk 200 µs 300 mV pk 200 µs -300 -300 For Notes to Electrical Performance Characteristics, refer to page 5 4 www.irf.com LS-SERIES Electrical Performance Characteristics Parameter Turn-on Overshoot (VOS) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D Turn-on Delay (TDLY) Group A Subgroup 4,5,6 Isolation Conditions -55°C ≤ TC ≤ +85°C VIN = 28V DC ± 5%, CL = 0 unless otherwise specified Limits Unit Min Nom 10% Load, Full Load Notes 4,12 0 Capacitive Load (CL) LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S LS2805D LS2812D LS2815D Line Rejection ( continued ) IOUT = 100% rated load No effect on DC performance Notes 1, 4, 7 Each output on duals 1 IOUT = 100% rated load DC to 50KHz, Notes 1, 4 35 1 Input to Output or Any Pin to Case except pin 3, test @ 500VDC 100 150 250 330 500 1000 1000 500 1000 1000 10 mV 2500 2500 2200 1000 180 120 500 90 60 µF 50 dB 80 MIL-HDBK-217F2, SF, 35°C ms MΩ Device Weight MTBF Max 6 4.0 x 10 g Hr Notes for Electrical Performance Characteristics Table 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Parameter is tested as part of design characterization or after design changes. Thereafter, parameter shall be guaranteed to the limits specified. Parameter verified during line and load regulation tests. Output load current must be distributed such that at least 20% of the total load current is being provided by one of the outputs. 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 using the circuit on page 6. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance. For a capacitive load in excess of the maximum limit, consult the factory. Overload power dissipation is defined as the device power dissipation with the load set such that V OUT = 90% of nominal. Load step transition time ≤ 10 µs. Recovery time is measured from the initiation of the transient to where V OUT 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 4) to the point where VOUT = 90% of nominal. For operation at temperatures between +85°C and 125°C, de-rate the maximum output power linearly from 100% to 75%. End of life (EOL) is ±3% www.irf.com 5 LS-SERIES Circuit for Measuring Output Ripple Voltage 50 Ω 50 Ω Coax 1 µF Oscilliscope or equivalent with 10 MHz bandwidth, multiply readings by 2. 0.1 µF + Vout 50 Ω Termination DUT Return RL for IRATED Radiation Performance Characterstics Test Conditions Min Total Ionizing Dose ( Gamma ) MIL-STD-883, Method 1019 Operating bias applied during exposure, Full Rated Load, VIN = 28V 100 Single Event Effects SEU, SEL, SEGR, SEB Heavy ions (LET) Operating bias applied during exposure, Full Rated Load, VIN = 28V >82 Typ Highest Level Tested Unit Krads (Si) 82 MeV-cm2 /mg International Rectifier currently does not have a DSCC certified Radiation Hardness Assurance Program. 6 www.irf.com LS-SERIES LS Series Output Voltage Adjustment Output of LS series can be adjusted to be greater or less than the nominal output voltage with an external resistor. However, the ranges of the output voltages are limited depending on the model as specified in Table 1 and 2. An approximate value of the resistor can be determined using the following formula. For Single Output Model: For Dual Output Model: Radj = Radj = A - (B x Vout) (C x Vout) - D A - (B x 2Vout) (C x 2Vout) - D Where: Radj is the value of the external resistor in kilo-ohms, Rdown or Rup in Figure 1 or 2. Power rating of the resistor shall be ≥ 0.125W. Metal film resistor with temperature coefficient of ≤ ±50 ppm and tolerance of ≤ 1% is recommended. However, the final selection is dependent on specific design requirements. Vout is the desired output voltage in volts. A, B, C, and D are unique constants depending on the model as shown in Table 1 for single output models and Table 2 for dual output models. Table 1: Single Output Voltage Ranges and Constants Model LS2801R5S LS2802R5S LS2803R3S LS2805S LS2812S LS2815S www.irf.com Output Voltage Range (V) (1) A B C D 1.500 to 1.600 69.65 32.39 8.75 13.13 1.400 to 1.500 56.85 40.47 7.14 10.72 2.500 to 2.750 48.42 13.04 3.52 8.81 2.250 to 2.500 39.52 21.19 2.88 7.19 3.300 to 3.630 43.48 9.25 2.50 8.25 2.970 to 3.300 35.48 16.18 2.04 6.73 5.000 to 5.500 119.48 20.00 2.27 11.36 4.500 to 5.000 97.52 29.31 1.85 9.27 12.000 to 13.200 295.22 19.98 2.27 27.24 10.800 to 12.000 241.01 53.31 1.85 22.24 15.000 to 16.500 370.61 19.98 2.27 34.05 13.500 to 15.000 302.55 63.61 1.85 27.80 7 LS-SERIES Table 2: Dual Output Voltage Ranges and Constants Model Voltage Range of Each Output (±Vout) (1) A B C D ±5.000 to ±5.500 196.91 17.12 1.71 17.12 LS2805D LS2812D LS2815D ±4.500 to ±5.000 160.74 31.11 1.40 13.97 ±12.000 to ±13.200 475.43 17.05 1.71 40.92 ±10.800 to ±12.000 388.10 58.04 1.39 33.41 ±15.000 to ±16.500 594.31 17.03 1.70 51.09 ±13.500 to ±15.000 485.10 69.47 1.39 41.70 Note: (1). Also the minimum and maximum adjustment limits of the output voltage. Placement of Radj An external resistor must be added in order to trim the output voltage of an LS converter. The placement of an Radj resistor (Rdown or Rup) must be as shown in Figure 1 for single output models and as per Figure 2 for dual output models. Please note that the connections are made to the specific pins. Rup is placed across Out Return and Out Adj pins for output voltage greater than nominal output. Similar connections apply for the dual output models. 8 www.irf.com LS-SERIES Figure 1: Radj Placement for Single Output Model 2XW 9LQ 9 +RXVH NHHSLQJ 9 6XSSO\ /HYHO 7UDQVODWRU )(7'ULYHU (0, )LOWHU 9LQ 5HWXUQ 2XW 5HWXUQ 5GRZQ 6KRUW&NW 2YHUORDG 3URWHFWLRQ ,QKLELW &DVH 0 2VFLOODWRU >=1 0 ($ 0 3:0 5XS 2XWSXW $GM 5DPS *HQHUDWRU 6DPSOH DQG+ROG )HHGEDFN 7ULJJHU www.irf.com 9 LS-SERIES Figure 2: Radj Placement for Dual Output Model 2XW 9LQ (0, )LOWHU 9LQ 5HWXUQ +RXVH NHHSLQJ 9 6XSSO\ 9 2XW 5HWXUQ 2XW /HYHO 7UDQVODWRU )(7'ULYHU ,QKLELW 5GRZQ 6KRUW&NW 2YHUORDG 3URWHFWLRQ &DVH 0 2VFLOODWRU >=1 0 ($ 0 3:0 5XS 2XWSXW $GM 5DPS *HQHUDWRU 6DPSOH DQG+ROG )HHGEDFN 7ULJJHU 10 www.irf.com LS-SERIES Efficiency, %n LS2801R5S Typical Efficiency at 25°C 70 60 50 40 30 20 18V 28V 40V 10 0 0 10 20 30 40 50 60 70 80 90 100 % of Rated Load Efficiency,% LS2802R5S Typical Efficiency at 25°C 100 90 80 70 60 50 40 30 20 10 0 18V 28V 40V 0 10 20 30 40 50 60 70 80 90 100 % of Rated Load www.irf.com 11 LS-SERIES Efficiency, %c LS2803R3S Typical Efficiency at 25°C 90 80 70 60 50 40 30 20 10 0 18V 28V 40V 0 10 20 30 40 50 60 70 80 90 100 % of Rated Load Efficiency, %y LS2805S Typical Efficiency at 25°C 100 90 80 70 60 50 40 30 20 10 0 18V 28V 40V 0 10 20 30 40 50 60 70 80 90 100 % of Rated Load 12 www.irf.com LS-SERIES Efficiency, %y LS2815S Typical Efficiency at 25°C 90 80 70 60 50 40 30 20 10 0 18V 28V 40V 0 10 20 30 40 50 60 70 80 90 100 % of Rated Load LS2815D Typical Efficiency at 25°C Efficiency, %c 100 80 18V 60 28V 40 40V 20 0 0 10 20 30 40 50 60 70 80 90 100 % of Rated Load www.irf.com 13 LS-SERIES Block Diagram - Single Output 9LQSXW 1 7 (0, )LOWHU ,QSXW 5HWXUQ ,QKLELW &DVH *URXQG 9RXW 9 %LDV 6XSSO\ 9 6 2XWSXW 5HWXUQ /HYHO 7UDQVODWRU )(7'ULYHU 2 6KRUW&NW 2YHUORDG 3URWHFWLRQ 4 3 0 5 >=1 ($ 0 2VFLOODWRU 0 2XWSXW $GMXVW 5DPS *HQHUDWRU 3:0 6DPSOH DQG+ROG )HHGEDFN 7ULJJHU Block Diagram - Dual Output 9LQSXW 1 (0, )LOWHU ,QSXW 5HWXUQ ,QKLELW &DVH *URXQG 8 9RXW 7 2XWSXW 5HWXUQ 6 9RXW 9 %LDV 6XSSO\ 9 2 /HYHO 7UDQVODWRU )(7'ULYHU 6KRUW&NW 2YHUORDG 3URWHFWLRQ 4 3 0 5 >=1 ($ 0 2VFLOODWRU 0 3:0 2XWSXW $GMXVW 5DPS *HQHUDWRU 6DPSOH DQG+ROG )HHGEDFN 7ULJJHU 14 www.irf.com LS-SERIES Mechanical Outline 2.300 0.375 ø 0.128 4 Plcs 1.550 0.050 0.25 Typ. 0.270 8 0.470 1 0.400 7 0.400 1.000 Ref 1.500 1.750 2.000 3 6 4 5 2 2 Eq Spaces @ 0.200 0.400 0.200 Pin ø 0.040 0.350 0.220 0.850 2.80 Ref 0.250 0.425 Max Tolerance: .XX = ±0.01 .XXX = ±0.005 Pin Designation (Single/Dual) www.irf.com Pin # Single Dual 1 + Input + Input 2 Input Return Input Return 3 Case Ground Case Ground 4 Inhibit Inhibit 5 Output Adjust Output Adjust 6 Output Return - Output 7 8 + Output NC Output Return + Output 15 LS-SERIES 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 N/A Radiographic 2012 Yes Yes External Visual 2009 Yes Yes c Notes: c d Best commercial practice. CK is DSCC class K compliant without radiation performance. No Suffix is a radiation rated device but not available as a DSCC qualified SMD per MIL-PRF-38534. International Rectifier currently does not have a DSCC certified Radiation Hardness Assurance Program. Standard Microcircuit Drawing Equivalence Table Standard M icrocircuit Draw ing Num ber IR Standard Part Num ber 5962-05238 LS 2801R5S 5962-05239 LS 2803R3S 5962-05240 LS2805S 5962-05241 LS2812D 5962-05242 LS2815D 5962-06241 LS2812S 5962-06242 LS2815S Part Numbering LS 28 05 S /EM Model Screening Level (Please refer to Screening Table) Input Voltage Nominal No Suffix, CK, EM, 28 = 28V Output Voltage 01R5 = 1.5V, 02R5 = 2.5V, 03R3 = 3.3V, 05 = 5V, 12 = 12V, 15 = 15V Output S = Single D = Dual WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, Tel: (310) 252-7105 IR SANTA CLARA: 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. 08/2006 16 www.irf.com