AFL12007SW/CH

PD-94460C IRF | Alldatasheet

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28V Input, Single Output Manufactured in a facility fully qualified to MIL-PRF- 38534, these converters are fabricated utilizing DSCC qualified processes. For available screening options, refer to device screening table in the data sheet. Variations in electrical, mechanical and screening can be accommodated. Contact IR Santa Clara for special requirements. These converters are hermetically packaged in two enclosure variations, utilizing copper core pins to minimize resistive DC losses. Three lead styles are available, each fabricated with International Rectifier’s rugged ceramic lead-to-package seal assuring long term hermeticity in the most harsh environments. HYBRID-HIGH RELIABILITY DC/DC CONVERTER PD-94460C

2 www.irf.com AFL28XXS Series Specifications Static Characteristics -55°C < TCASE < +125°C, 16V< VIN < 40V unless otherwise specified. For Notes to Specifications, refer to page 4 Parameter Group A Subgroups Test Conditions Min Nom Max Unit INPUT VOLTAGE Note 6 16 28 40 V OUTPUT VOLTAGE AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S 2, 3 2, 3 2, 3 2, 3 2, 3 2, 3 2, 3 VIN = 28 Volts, 100% Load 4.95 6.93 7.92 8.91 11.88 14.85 27.72 4.90 6.86 7.84 8.82 11.76 14.70 27.44 5.00 7.00 8.00 9.00 12.00 15.00 28.00 5.05 7.07 8.08 9.09 12.12 15.15 28.28 5.10 7.17 8.16 9.18 12.24 15.30 28.56 V OUTPUT CURRENT AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S VIN = 16, 28, 40 Volts - Note 6 11.4 9.0 8.0 4.0 A OUTPUT POWER AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S Note 6 108 120 112 W MAXIMUM CAPACITIVE LOAD Note 1 10,000 µF OUTPUT VOLTAGE TEMPERATURE COEFFICIENT V IN = 28 Volts, 100% Load - Note 1, 6 -0.015 +0.015 %/°C OUTPUT VOLTAGE REGULATION AFL2828S Line All Others Line Load 1, 2, 3 1, 2, 3 1, 2, 3 No Load, 50% Load, 100% Load VIN = 16, 28, 40 Volts -70 -20 -1.0 +70 +20 +1.0 mV mV OUTPUT RIPPLE VOLTAGE AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 VIN = 16, 28, 40 Volts, 100% Load, BW = 10MHz 100 mVpp Input voltage -0.5V to +50VDC Soldering temperature 300°C for 10 seconds Operating case temperature -55°C to +125°C Storage case temperature -65°C to +135°C Absolute Maximum Ratings

www.irf.com 3 AFL28XXS Series Static Characteristics (Continued) For Notes to Specifications, refer to page 4 Parameter Group A Subgroups Test Conditions Min Nom Max Unit INPUT CURRENT No Load Inhibit 1 Inhibit 2 2, 3 1, 2, 3 1, 2, 3 V IN = 28 Volts IOUT = 0 Pin 4 Shorted to Pin 2 Pin 12 Shorted to Pin 8 100 5.0 mA INPUT RIPPLE CURRENT AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 VIN = 28 Volts, 100% Load, BW = 10MHz mApp CURRENT LIMIT POINT As a percentage of full rated load VOUT = 90% VNOM, VIN = 28 Volts Note 5 115 105 125 125 115 140 LOAD FAULT POWER DISSIPATION Overload or Short Circuit 1, 2, 3 VIN = 28 Volts W EFFICIENCY AFL2805S AFL2807S AFL2808S AFL2809S AFL2812S AFL2815S AFL2828S 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 1, 2, 3 V IN = 28 Volts, 100% Load ENABLE INPUTS (Inhibit Function) Converter Off Sink Current Converter On Sink Current 1, 2, 3 1, 2, 3 Logical Low on Pin 4 or Pin 12 Note 1 Logical High on Pin 4 and Pin 12 - Note 9 Note 1 -0.5 2.0 0.8 100 100 V µA V µA SWITCHING FREQUENCY 1, 2, 3 500 550 600 KHz SYNCHRONIZATION INPUT Frequency Range Pulse Amplitude, Hi Pulse Amplitude, Lo Pulse Rise Time Pulse Duty Cycle 1, 2, 3 1, 2, 3 1, 2, 3 Note 1 Note 1 500 2.0 -0.5 700 0.8 100 KHz V V ns ISOLATION 1 Input to Output or Any Pin to Case (except Pin 3). Test @ 500VDC 100 MΩ DEVICE WEIGHT Slight Variations with Case Style 85 g MTBF MIL-HDBK-217F, AIF @ T C = 70°C 300 KHrs

4 www.irf.com AFL28XXS Series Dynamic Characteristics -55°C < TCASE < +125°C, VIN=28V unless otherwise specified. Notes to Specifications: 1. Parameters not 100% tested but are guaranteed to the limits specified in the table. 2. Recovery time is measured from the initiation of the transient to where V OUT has returned to within ±1.0% of VOUT at 50% load. 3. Line transient transition time ≥ 100µs. 4. Turn-on delay is measured with an input voltage rise time of between 100V and 500V per millisecond. 5. Current limit point is that condition of excess load causing output voltage to drop to 90% of nominal. 6. Parameter verified as part of another test. 7. All electrical tests are performed with the remote sense leads connected to the output leads at the load. 8. Load transient transition time ≥ 10µs. 9. Enable inputs internally pulled high. Nominal open circuit voltage ≈ 4.0VDC. Parameter Group A Subgroups Test Conditions Min Nom Max Unit LOAD TRANSIENT RESPONSE AFL2805S Amplitude Recovery Amplitude Recovery AFL2807S Amplitude Recovery Amplitude Recovery AFL2808S Amplitude Recovery Amplitude Recovery AFL2809S Amplitude Recovery Amplitude Recovery AFL2812S Amplitude Recovery Amplitude Recovery AFL2815S Amplitude Recovery Amplitude Recovery AFL2828S Amplitude Recovery Amplitude Recovery 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 4, 5, 6 Note 2, 8 Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% Load Step 50% ⇔ 100% Load Step 10% ⇔ 50% -450 -450 -500 -500 -500 -500 -600 -600 -750 -750 -750 -750 -1200 -1200 450 200 450 400 500 200 500 400 500 200 500 400 600 200 600 400 750 200 750 400 750 200 750 400 1200 200 1200 400 mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs mV µs LINE TRANSIENT RESPONSE Amplitude Recovery Note 1, 2, 3 VIN Step = 16 ⇔ 40 Volts -500 500 500 mV µs TURN-ON CHARACTERISTICS Overshoot Delay 4, 5, 6 4, 5, 6 VIN = 16, 28, 40 Volts. Note 4 Enable 1, 2 on. (Pins 4, 12 high or open) 4.0 250 mV ms LOAD FAULT RECOVERY Same as Turn On Characteristics. LINE REJECTION MIL-STD-461D, CS101, 30Hz to 50KHz Note 1 40 50 dB

www.irf.com 5 AFL28XXS Series Block Diagram Figure I. Single Output Figure II. Enable Input Equivalent Circuit Pin 4 or Pin 12 1N4148 100K 290K 150K 2N3904 +5.6V Disable Pin 2 or Pin 8 Circuit Operation and Application Information Inhibiting Converter Output (Enable) As an alternative to application and removal of the DC voltage to the input, the user can control the converter output by providing TTL compatible, positive logic signals to either of two enable pins (pin 4 or 12). The distinction between these two signal ports is that enable 1 (pin 4) is referenced to the input return (pin 2) while enable 2 (pin 12) is referenced to the output return (pin 8). Thus, the user has access to an inhibit function on either side of the isolation barrier. Each port is internally pulled “high” so that when not used, an open connection on both enable pins permits normal converter operation. When their use is desired, a logical “low” on either port will shut the converter down. The AFL series of converters employ a forward switched mode converter topology. (refer to Figure I) Operation of the device is initiated when a DC voltage whose magnitude is within the specified input limits is applied between pins 1 and 2. If pin 4 is enabled (at a logical 1 or open) the primary bias supply will begin generating a regulated housekeeping voltage bringing the circuitry on the primary side of the converter to life. A power MOSFET is used to chop the DC input voltage into a high frequency square wave, applying this chopped voltage to the power transformer at the nominal converter switching frequency. Maintaining a DC voltage within the specified operating range at the input assures continuous generation of the primary bias voltage. The switched voltage impressed on the secondary output transformer winding is rectified and filtered to generate the converter DC output voltage. An error amplifier on the secondary side compares the output voltage to a precision reference and generates an error signal proportional to the difference. This error signal is magnetically coupled through the feedback transformer into the controller section of the converter varying the pulse width of the square wave signal driving the MOSFET, narrowing the width if the output voltage is too high and widening it if it is too low, thereby regulating the output voltage. Remote Sensing Connection of the + and - sense leads at a remotely located load permits compensation for excessive resistance between the converter output and the load when their physical separation could cause undesirable voltage drop. This connection allows regulation to the placard voltage at the point of application. When the remote sensing feature is not used, the sense leads should be connected to their respective output terminals at the converter. Figure III. llustrates a typical remotely sensed application. 1 + Input Enable 1 4 Sync Output 5

6 Sync Input

2 Input Return

& Ref Share Amplifier Sense Amplifier 7 +Output 10 +Sense

11 Share

12 Enable 2

9 Sense Return

8 Output Return

6 www.irf.com AFL28XXS Series Figure III. Preferred Connection for Parallel Operation Synchronization of Multiple Converters Parallel Operation-Current and Stress Sharing Internally, these ports differ slightly in their function. In use, a low on Enable 1 completely shuts down all circuits in the converter, while a low on Enable 2 shuts down the secondary side while altering the controller duty cycle to near zero. Externally, the use of either port is transparent to the user save for minor differences in stndby current. (See specification table). When operating multiple converters, system requirements often dictate operation of the converters at a common frequency. To accommodate this requirement, the AFL series converters provide both a synchronization input and a synchronization output. The sync input port permits synchronization of an AFL converter to any compatible external frequency source operating between 500KHz and 700KHz. This input signal should be referenced to the input return and have a 10% to 90% duty cycle. Compatibility requires transition times less than 100ns, maximum low level of +0.8Vand a minimum highvel of +2.0V. The sync output of another converter which has been designated as the master oscillator provides a convenient frequency source for this mode of operation. When external synchronization is not required, the sync in pin should be left open (unconnected )thereby permitting the converter to operate at its’ own internally set frequency. The sync output signal is a continuous pulse train set at 550 ± 50KHz, with a duty cycle of 15 ± 5%. This signal is referenced to the input return and has been tailored to be compatible with the AFL sync input port. Transition times are less than 100ns and the low level output impedance is less than 50 Ω. This signal is active when the DC input voltage is within the specified operating range and the converter is not inhibited. This output has adequate drive reserve to synchronize at least five additional converters. A typical connection is illustrated in Figure III. Figure III. illustrates the preferred connection scheme for operation of a set of AFL converters with outputs operating in parallel. Use of this connection permits equal sharing among the members of a set whose load current exceeds the capacity of an individual AFL. An important feature of Optional Synchronization Connection Power Input (Other Converters) Share Bus AFL - Sense Enable 2 + Vout Return + Sense Share Vin Rtn Case Enable 1 Sync Out Sync In AFL - Sense Enable 2 + Vout Return + Sense Share Vin Rtn Case Enable 1 Sync Out Sync In AFL - Sense Enable 2 + Vout Return + Sense Share Vin Rtn Case Enable 1 Sync Out Sync In to Load the AFL series operating in the parallel mode is that in addition to sharing the current, the stress induced by temperature will also be shared. Thus if one member of a paralleled set is operating at a higher case temperature, the current it provides to the load will be reduced as compensation for the temperature induced stress on that device.

www.irf.com 7 AFL28XXS Series A conservative aid to estimating the total heat sink surface area (A HEAT SINK ) required to set the maximum case temperature rise ( ∆T) above ambient temperature is given by the following expression: A HEAT SINK ≈ ⎭ − −∆T P80 3008 5 143 where PP Eff OUT == − ⎧⎨⎩ ⎫⎬⎭ Case temperature rise above ambient Device dissipation in Watts 1 1 and the required heat sink area is From the Specification Table, the worst case full load efficiency for this device is 83%; therefore the power dissipation at full load is given by Because of the incorporation of many innovative technological concepts, the AFL series of converters is capable of providing very high output power from a package of very small volume. These magnitudes of power density can only be obtained by combining high circuit efficiency with effective methods of heat removal from the die junctions. This requirement has been effectively addressed inside the device; but when operating at maximum loads, a significant amount of heat will be generated and this heat must be conducted away from the case. To maintain the case temperature at or below the specified maximum of 125°C, this heat must be transferred by conduction to an appropriate heat dissipater held in intimate contact with the converter base-plate. When operating in the shared mode, it is important that symmetry of connection be maintained as an assurance of optimum load sharing performance. Thus, converter outputs should be connected to the load with equal lengths of wire of the same gauge and should be connected to a common physical point, preferably at the load along with the converter output and return leads. All converters in a paralleled set must have their share pins connected together. This arrangement is diagrammatically illustrated in Figure III showing the output and return pins connected at a star point which is located close as possible to the load. As a consequence of the topology utilized in the current sharing circuit, the share pin may be used for other functions. In applications requiring only a single converter, the voltage appearing on the share pin may be used as a “current monitor”. The share pin open circuit voltage is nominally +1.00V at no load and increases linearly with increasing total output current to +2.20V at full load. 1Sil-Pad is a registered Trade Mark of Bergquist, Minneapolis, MN Thermal Considerations Because the effectiveness of this heat transfer is dependent on the intimacy of the baseplate/heatsink interface, it is strongly recommended that a high thermal conductivity heat transferring medium is inserted between the baseplate and heatsink. The material most frequently utilized at the factory during all testing and burn-in processes is sold under the trade name of Sil-Pad® 4001 . This particular product is an insulator but electrically conductive versions are also available. Use of these materials assures maximum surface contact with the heat dissipater thereby compensating for any minor surface variations. While other available types of heat conductive materials and thermal compounds provide similar effectiveness, these alternatives are often less convenient and can be somewhat messy to use. As an example, it is desired to maintain the case temperature of an AFL2815S at ≤ +85°C while operating in an open area whose ambient temperature is held at a constant +25°C; then Thus, a total heat sink surface area (including fins, if any) of 71 in2 in this example, would limit case rise to 60°C above ambient. A flat aluminum plate, 0.25" thick and of approximate dimension 4" by 9" (36 in 2 per side) would suffice for this application in a still air environment. Note that to meet the criteria in this example, both sides of the plate require unrestricted exposure to the ambient air. ⎭ =• =120 1 83 1 120 0 205 24 6. .. WA = 60 80 24.6 inHEAT SINK 0.85• ⎭ −= −143 230 7 1

8 www.irf.com AFL28XXS Series General Application Information The AFL28XXS series of converters are capable of providing large transient currents to user loads on demand. Because the nominal input voltage range in this series is relatively low, the resulting input current demands will be correspondingly large. It is important therefore, that the line impedance be kept very low to prevent steady state and transient input currents from degrading the supply voltage between the voltage source and the converter input. In applications requiring high static currents and large transients, it is recommended that the input leads be made of adequate size to minimize resistive losses, and that a good quality capacitor of approximately 100 µfd be connected directly across the input terminals to assure an adequately low impedance at the input terminals. Table I relates nominal resistance values and selected wire sizes. Input Filter Undervoltage Lockout The AFL28XXS series converters incorporate a two stage LC input filter whose elements dominate the input load impedance characteristic during the turn-on. The input circuit is as shown in Figure IV. Figure IV. Input Filter Circuit A minimum voltage is required at the input of the converter to initiate operation. This voltage is set to 14V ± 0.5V. To preclude the possibility of noise or other variations at the input falsely initiating and halting converter operation, a hysteresis of approximately 1.0V is incorporated in this circuit. Thus if the input voltage droops to 13V ± 0.5V, the converter will shut down and remain inoperative until the input voltage returns to ≈14V. Output Voltage Adjust Pin 1 Pin 2 900nH 130nH 6 µfd 11.2 µfd In addition to permitting close voltage regulation of remotely located loads, it is possible to utilize the converter sense pins to incrementally increase the output voltage over a limited range. The adjustments made possible by this method are intended as a means to “trim” the output to a voltage setting for some particular application, but are not intended to create an adjustable output converter. These output voltage setting variations are obtained by connecting an appropriate resistor value between the +sense and -sense pins while connecting the -sense pin to the output return pin as shown in Figure V. below. The range of adjustment and corresponding range of resistance values can be determined by use of the following equation. R = 100 - - . 0 2 5 adj NOM OUT NOM

• ⎧⎨ V VV Where VNOM = device nominal output voltage, and VOUT = desired output voltage Figure V. Connection for VOUT Adjustment Finding a resistor value for a particular output voltage, is simply a matter of substituting the desired output voltage and the nominal device voltage into the equation and solving for the corresponding resistor value. Enable 2 Share + Sense - Sense Return + Vout To Load RADJ AFL28xxS Note: Radj must be set ≥ 500Ω Attempts to adjust the output voltage to a value greater than 120% of nominal should be avoided because of the potential of exceeding internal component stress ratings and subsequent operation to failure. Under no circumstance should the external setting resistor be made less than 500Ω. By remaining within this specified range of values, completely safe operation fully within normal component derating limits is assured. Examination of the equation relating output voltage and resistor value reveals a special benefit of the circuit topology utilized for remote sensing of output voltage in the AFL28XXS series of converters. It is apparent that as the resistance increases, the output voltage approaches the nominal set value of the device. In fact the calculated limiting value of output voltage as the adjusting resistor becomes very large is ≈ 25mV above nominal device voltage. The consequence is that if the +sense connection is unintentionally broken, an AFL28XXS has a fail-safe output voltage of Vout + 25mV, where the 25mV is independent of the nominal output voltage. It can be further demonstrated that in the event of both the + and - sense connections being broken, the output will be limited to Vout + 440mV. This 440mV is also essentially constant independent of the nominal output voltage.

Table 1. Nominal Resistance of Cu Wire consider an AFL2815S operating at full power of 120W. when establishing the worst case TTL switching levels. These drops will effectively impart a shift to the logic levels.

10 www.irf.com AFL28XXS Series Mechanical Outlines Case X Case W Pin Variation of Case Y 1.260 1.500 2.500 2.760 3.000 ø 0.128 0.250 1.000 Ref 0.200 Typ Non-cum 0.050 0.220 Pin ø 0.040 0.238 max 0.380 Max 2.975 max 7 12 0.050 0.220 0.250 1.000 Pin ø 0.040 0.525 0.380 Max 2.800 0.42 Case Y Case Z Pin Variation of Case Y 1.500 1.750 2.500 0.25 typ 1.150 0.050 0.220 7 12 1.750 0.375 2.00 0.250 1.000 Ref 0.200 Typ Non-cum Pin ø 0.040 0.300 ø 0.140 0.238 max 0.380 Max 2.975 max 0.050 0.220 0.250 1.000 Ref Pin ø 0.040 0.525 0.380 Max 2.800 0.36 BERYLLIA WARNING: These converters are hermetically sealed; however they contain BeO substrates and should not be ground or subjected to any other operations including exposure to acids, which may produce Beryllium dust or fumes containing Beryllium Tolerances, unless otherwise specified: .XX = ±0.010 .XXX = ±0.005

www.irf.com 11 AFL28XXS Series Pin Designation Pin # Designation 1 + Input

3 Case Ground

4 Enable 1

5 Sync Output

Standard Microcircuit Drawing Equivalence Table Standard Microcircuit IR Standard Drawing Number Part Number 5962-94721 AFL2805S 5962-96659 AFL2808S 5962-94772 AFL2812S 5962-94723 AFL2815S 5962-96899 AFL2828S

12 www.irf.com AFL28XXS Series WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, Tel: (310) 322 3331 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. 12/2006 Part Numbering Notes: /G129 Best commercial practice /G130 Sample tests at low and high temperatures /G131 -55°C to +105°C for AHE, ATO, ATW Device Screening Requirement MIL-STD-883 Method No Suffix ES /c100 HB CH Temperature Range -20°C to +85°C -55°C to +125°C /c101 -55°C to +125°C -55°C to +125°C Element Evaluation MIL-PRF-38534 N/A N/A N/A Class H Non-Destructive Bond Pull Internal Visual 2017 /c99 Yes Yes Yes Temperature Cycle 1010 N/A Cond B Cond C Cond C Constant Acceleration 2001, Y1 Axis N/A 500 Gs 3000 Gs 3000 Gs PIND 2020 N/A N/A N/A N/A Burn-In 1015 N/A 48 hrs@hi temp 160 hrs@125°C 160 hrs@125°C Final Electrical MIL-PRF-38534 25°C 25°C /c100 -55°C, +25°C, -55°C, +25°C, ( Group A ) & Specification +125°C +125°C PDA MIL-PRF-38534 N/A N/A N/A 10% Seal, Fine and Gross 1014 Cond A Cond A, C Cond A, C Cond A, C Radiographic 2012 N/A N/A N/A N/A External Visual 2009 /c99 Yes Yes Yes N/A N/A2023 N/A N/A AFL 28 05 S X /CH Model Input Voltage 28 = 28V 50 = 50V 120 = 120V 270 = 270V Output Voltage 05 = 5V, 06 = 6V 07 = 7V, 08 = 8V 09 = 9V, 12 = 12V 15 = 15V, 28 = 28V Output S = Single Case Style W, X, Y, Z Screening Level (Please refer to Screening Table) No suffix, ES, HB, CH