sMFL single and dual dc-dc converters - Interpoint

1 DESCRIPTIONThe Interpoint SMFL Series of 28 VOLT dc-dc converters offers up to 65 watts of power in a radiation hardened design. The low profile SMFL converters are manufactured in our fully certified and qualified MIL-PRF-38534 Class K production facility and packaged in hermetically sealed steel cases. They are ideal for use in programs requiring high reliability, small size, and high levels of radiation hardness full output power over is available over the temperature range of -55 C to +125 C with a 28 volt nominal input. On dual output models, up to 70% of the rated output power can be drawn from either the positive or negative outputs. The welded, hermetically sealed package is only x x inches. Screening SMFL converters offer screening options to space prototype (O), Class H or K and radiation hardness assurance (RHA) levels P - 30 krad(Si), L - 50 krad(Si) or R - 100 krad(Si).

2 single event effects (SEE) LET performance to 86 MeV cm2/mg. See Table 9 on page 13 and Figure 2 on page 3 for more FeatureSThe SMFL Series converters are switching regulators that use a quasi-square wave, single ended forward converter design with a constant switching frequency of 600 between input and output circuits is provided with a transformer in the forward path and wide bandwidth magnetic coupling in the feedback control loop. The SMFL Series uses a unique dual loop feedback technique that controls output current with an inner feedback loop and output voltage with a cascaded voltage mode feedback additional secondary current mode feedback loop improves transient response in a manner similar to primary current mode control and allows for ease of load regulation is achieved through a wide-bandwidth magnetic feedback circuit.

3 InhibitThe SMFL Series converters have two inhibit terminals (Inhibit 1 and Inhibit 2) that can be used to disable power conversion, resulting in a very low quiescent input current. See Table 5 on page 6 for Radiation tolerant space dc-dc converter - single event effects (SEE) LET performance to 86 MeV cm2/mg - Total ionizing dose (TID) guaranteed per MIL-STD-883 method 1019, radiation hardness assurance (RHA) P = 30 krad(Si), L = 50 krad(Si), R = 100 krad(Si) - 50 - 300 rad(Si)/sec dose rate (Condition A) - 10 mrad(Si)/sec dose rate (Condition D) Parallel up to 3 converters maximum recommended power is 80% of the total available power. Operating temperature -55 C to +125 C Qualified to MIL-PRF-38534 Class H and K Input voltage range 16 to 40 volts Transient protection up to 80 volts for 50 ms - converter will shut down at an input voltage above approximately 45 volts Fully isolated, magnetic feedback Fixed high switching frequency Remote sense and output trim on single output models Primary and secondary inhibit function Synchronization input and output Indefinite short circuit protection High power density with up to 85% typical efficiencyMODELSOUTPUT VOLTAGE (V)

4 55 1212 1515 Crane Aerospace & Electronics Power Solutions SMFL single and Dual dc-dc ConvertersPage 1 of 1516 TO 40 VOLT INPUT 45 TO 65 WATTSMFL Rev AG - Aerospace & ElectronicsPower Solutions Interpoint Products16706 13th Ave W, Lynnwood WA 98037+1 may be synced to an external clock (525 to 675 kHz)or to one another by using the sync in or out pins. See Table 5 on page 6 for anD trimSingle output models provide sense to maintain voltage at the load. The converters output voltage can also be trimmed up. See Figure Sharing anD Parallel OPeratiOnFor increased power parallel up to 3 converters . The maximum recommended power is 80% of the total available power. Multiple SMFL converters may be used in parallel to drive a common load. Only single output models with Sense and Sense Return can be used in the share mode.

5 In this mode of operation the load current is shared by two or three SMFL converters . In current sharing mode, one SMFL converter is designated as a master. The Slave pin (pin 11) of the master is left unconnected and the Master/Inhibit 2 pin (pin 12) of the master is connected to the Slave pin (pin 11) of the slave units. The units designated as slaves have the Master/Inhibit 2 pin (pin 12) connected to the Sense Return pin (pin 9) of the master unit. Figure 2 on page 3 shows the typical setup for two or three units in parallel. A second slave unit may be placed in parallel with a master and slave; this requires the Triple pin (pin 3) of the master unit to be connected to the Sense Return pins (pin 9) shown in Figure 2 on page current sharing mode, the converters function as a current source. For this reason it is important that their outputs be connected to the common ground at all times to prevent an excessively high voltage at their outputs.

6 RL123456 REMOTE SENSE CONNECTION121110987 +28V +InhibitSync In123456 OUTPUT VOLTAGE ADJUST CONNECTION12111098728V +InhibitSync InRAPositive InputInput CommonTriple (TRI)Inhibit 1 Sync OutSync InMaster/Inhibit 2 SlavePositive SenseSense ReturnOutput CommonPositive OutputPositive InputInput CommonTriple (TRI)Inhibit 1 Sync OutSync InMaster/Inhibit 2 SlavePositive SenseSense ReturnOutput CommonPositive OutputRL +Figure 1: SenSe cOnnectiOnS anD trim table single OutPut mODelSNotes1. When using remote sense for voltage compensation or when using remote sense for trim, the output will drift over temperature. Contact Applications Engineering for more information Do not exceed the maximum rated power or INCREASERA ( ) V5 V12 V15 Crane Aerospace & Electronics Power 2 of 15 SMFL single and Dual dc-dc Converters16 TO 40 VOLT INPUT 45 TO 65 WATT SMFL Rev AG - InputInput CommonTriple (TRI)Inhibit 1 Sync OutSync In23456123456123456 CONNECT TRIPL (TRI) ONLY WHEN 2 SLAVES ARE USED121110987121110987121110987 Master/Inhibit 2 SlavePositive SenseSense ReturnOutput CommonPositive OutputMASTERSLAVE 1 SLAVE 228V +InhibitSync InPositive InputInput CommonTriple (TRI)Inhibit 1 Sync OutSync InMaster/Inhibit 2 SlavePositive SenseSense ReturnOutput CommonPositive OutputPositive InputInput CommonTriple (TRI)Inhibit 1 Sync OutSync InMaster/Inhibit 2 SlavePositive SenseSense ReturnOutput CommonPositive OutputRL +Figure 2.

7 Parallel cOnnectiOnS single OutPut mODelSNotes1. No one converter may carry more than its maximum rated current. 2. Individual converter operation, load and layout may affect the actual current shared. Contact Applications Engineering for more information When paralleling SMFLs a diode is required at the input of each inhibit pin as SMFLs do not have an internal diode on the inhibit pin. Crane Aerospace & Electronics Power 3 of 15 SMFL single and Dual dc-dc Converters16 TO 40 VOLT INPUT 45 TO 65 WATT SMFL Rev AG - 3: Pin OutAngled corner indicates pin VIEW SMFLS tandard case U, short leads(Pin side, marked side)PIN OUTPinSingle OutputDual Output1 Positive InputPositive Input2 Input CommonInput Common3 Triple (TRI)Triple (TRI)4 Inhibit 1 (INH1)Inhibit 1 (INH1)5 Sync OutSync Out6 Sync InSync In7 Positive OutputPositive Output8 Output CommonOutput Common9 Sense ReturnNegative Output10 Positive SenseNo connection11 SlaveSlave12 Master/Inhibit 2(MSTR/INH2)Master/Inhibit 2(MSTR/INH2)PINS NOT IN USE Triple (TRI)Leave unconnectedInhibit 1 (INH1)Leave unconnectedSync OutLeave unconnectedSync InConnect to Input CommonSense ReturnConnect to appropriate outputsPositive SenseConnect to appropriate outputsSlaveLeave unconnectedMaster/Inhibit 2(MSTR/INH2)Leave unconnectedtable 1: Pin Outtable 2.

8 PinS nOt in uSeSee Figure 16 on page 12 for dimensions for case U. Crane Aerospace & Electronics Power 4 of 15 SMFL single and Dual dc-dc Converters16 TO 40 VOLT INPUT 45 TO 65 WATT SMFL Rev AG - NUMBERING KEYSMFL 28 15 D / K RBase ModelInput VoltageOutput VoltageEnvironmental ScreeningNumber of Outputs(S = single , D = dual)Radiation HardnessAssurance (RHA)SMD NUMBERSS tandard Microcircuit drawing (SMd)SMFL SerieS SiMiLar Part5962R0621302 KXCSMFL283R3S/KR5962R9316302 KXCSMFL2805S/KR5962R9316202 KXCSMFL2812S/KR5962R9316102 KXCSMFL2815S/KR5962R9319102 KXCSMFL2805D/KR5962R9319202 KXCSMFL2812D/KR5962R9319302 KXCSMFL2815D/KRThe SMD number shown is for Class K screening, radiation hardness assurance (RHA) level R. For exact specifications for an SMD product, refer to the SMD drawing. SMDs can be downloaded from 4: mODel numbering Keytable 3: SmD number crOSS reFerencetable 4: mODel number OPtiOnSMODEL NUMBER OPTIONS to deterMine the ModeL nuMber enter one oPtion FroM each category in the ForM Model and Input VoltageOutput Voltage 1 Number of Outputs 2 Case OptionScreening 3 RHA 4 OPTIONSSMFL283R3, 05, 12, 15S(U, leave blank)OO05, 12, 15 DHPKLRFILL IN FOR MODEL # 5 SMFL28 / _____ Notes1.

9 Output Voltage: An R indicates a decimal point. 3R3 is volts out. The value of 3R3 is only available in single output models. 2. Number of Outputs: S is a single output and D is a dual Screening: A screening level of O is a space prototype and is only used with RHA O. See Table 9 on page 13 and Table 10 on page 14 for more 4. RHA: Interpoint model numbers use an O in the RHA designator position to indicate the - (dash) RHA level of MIL-PRF-38534, which is defined as no RHA. RHA O is only available with screening level O. See Table 11 on page 15 for more If ordering by model number add a -Q to request solder dipped leads (SMFL2805S/KR-Q). Crane Aerospace & Electronics Power 5 of 15 SMFL single and Dual dc-dc Converters16 TO 40 VOLT INPUT 45 TO 65 WATT SMFL Rev AG - 5: OPerating cOnDitiOnS, all mODelS, 25 c caSe, 28 Vin, 100% lOaD, unleSS OtherwiSe SPeciFieD.

10 ALL MODELSPARAMETERCONDITIONSMINTYPMAXUNITSL EAD SOLDERING TEMPERATURE 110 SECONDS MAX. 300 CSTORAGE TEMPERATURE 1-65 +150 CCASE OPERATING TEMPERATUREFULL POWER-55 +125 CABSOLUTE 1-55 +135 DERATING OUTPUT POWER/CURRENT 1 LINEARLYFrom 100% at 125 C to 0% at 135 CESD RATING 1, 2 MIL STD 883 METHOD 3015>8000V MIL-PRF-38534, 3 BISOLATION: INPUT TO OUTPUT, INPUT TO@ 500 VDC AT 25 C100 MegohmsCASE, OUTPUT TO CASE 3 INPUT TO OUTPUT CAPACITANCE 1 150 pFCURRENT LIMIT 4% OF FULL LOAD 125 %UNDERVOLTAGE LOCKOUT 1 RISING VIN (TURN ON) -55 C TO +125 CFALLING VIN (TURN OFF) REJECTION 1 50 dBSWITCHING FREQUENCY-55 C TO +125 C525 675kHzSYNCHRONIZATION ININPUT FREQUENCY525 675kHz -55 C TO +125 CDUTY CYCLE 140 60%ACTIVE LOW HIGH TO INPUT COMMONIF NOT USED CONNECT TO INPUT COMMONSYNCHRONIZATION OUTREFERENCED TO INPUT COMMONIF NOT USED LEAVE UNCONNECTEDINHIBIT 1 ACTIVE LOW (OUTPUT DISABLED) INHIBIT PIN PULLED LOW not apply a voltage to the inhibit pin.