LAMBDA ADVANCED ANALOG INC. λ AHF2815T Series Triple Output, Hybrid - High Reliability DC/DC Converter DESCRIPTION FEATURES The AHF2800T Series of DC/DC converters provide 8 watts of power and an extended temperature range for use in military and industrial applications. Designed to the nominal input requirements of MILSTD-704, thse devices have nominal 28VDC inputs with +5V and ±12V or +5V and ±15V triple outputs to satisfy a wide range of requirements. The basic circuit utilizes a pulse width modulated, feed forward topology at a nominal switching frequency of 550KHx. Input to output isolation is achieved through the use of transformers in the forward and feedback circuits. The poprietary magnetic feedback circuit provides for an extremely wide bandwidth control loop with a high phase margin. The closed loop frequency response of this converter family extends to approximately 50KHz, resulting in superior line and load transient characteristics. This feedback method is also inherently temperature and radiation insensitive. This gives the AHF Series an important advantage over converters that incorporate optocouplers in their design. Manufactured in a facility fully qualified to MIL-PRF38534, these converters are available in four screening grades to satisfy a wide range of requirements. The CH grade is fully compliant to the requirements of MIL-PRF-38534 for class H. The HB grade is processed and screened to the class H requirement, but may not necessarily meet all of the other MIL-PRF-38534 requirements, e.g., element evaluation and Periodic Inspection (P.I.) not required. Both grades are tested to meet the complete group "A" test specification over the full military temperature range without output power deration. Two grades with more limited screening are also available for use in less demanding applications. Variations in electrical, mechanical and screening can be accommodated. Contact Lambda Advanced Analog for special requirements. 1 n 16 To 40 VDC Input Range (28VDC Nominal) n 5V, ± 15 Volt Output n Indefinite Short Circuit and Overload Protection n 8 Watts Output Power n Fast Loop Response for Superior Transient Characteristics n Operating Temperature Range from -55°C to +125°C Available n Popular Industry Standard Pin-Out n Resistance Seam Welded Case for Superior Long Term Hermeticity n Efficiencies Up to 75% n Shutdown from External Signal n 400,000 Hour MTBF at 85% n Constant Switching Frequency (550 KHz Nominal) SPECIFICATIONS TCASE = -55°C to +125°C, VIN = +28 V ±5% unless otherwise specified7 TYPICAL CHARACTERISTICS Temperature Range7 Operating -55°C to 125°C case Storage -65°C to +135°C 100 megaohms at 500 volts DC 35 grams 550 kHz Isolation Weight Conversion frequency Conditions AHF2815T Limits Min Ma x -55°C - Tc - +125°C, VIN = 28 VDC Test Symbol STATIC CHARACTERISTICS OUTPUT Voltage1 VOUT ±5%, CL=0, unless otherwise specified7 IOUT = 0 (main) TC = 25°C Over Temp TC = 25°C Over Temp 1 IOUT = 0 (dual) Current1,2,3 IOUT 1,4 Ripple Voltage Power 1,2,3 REGULATION Line1,3 Load 1,3 VRIP POUT VRLINE VRLOAD VIN = 16, 28, and 40 VDC (main) VIN = 16, 28, and 40 VDC (dual)1 VIN = 16, 28, and 40 VDC BW = DC to 2 MHz (main) VIN = 16, 28, and 40 VDC BW = DC to 2 MHz (dual) VIN = 16, 28, and 40 VDC (main) (+dual) (-dual) (total) 4.95 5.05 V 4.90 5.10 V ±14.50 ±15.50 V ±14.35 ±15.65 V 120 1200 mA 0.0 ±66.7 mA 60 mV p-p 80 5 1.5 1.5 8 VIN = 16, 28, and 40 VDC IOUT = 120, 600, 1200 mA (main) VIN = 16, 28, and 40 VDC (dual) IOUT = 0, ±33.4, ±66.7 mA (dual) VIN = 16, 28, and 40 VDC IOUT = 120, 600, 1200 mA (main) VIN = 16, 28, and 40 VDC IOUT = 0, ±33.4, ±66.7 mA (dual) INPUT Current IIN Ripple Current4 IRIP EFFICIENCY EFF ISOLATION ISO Input to output or any pin to case (except pin 6) at 500 VDC, Tc = +25°C LOAD FAULT POWER DISSIPATION 3 PD Over Load, TC = +25°C5 Short Circuit, TC = +25°C SWITCHING FREQUENCY FS INHIBIT OPEN CIRCUIT VOLTAGE VOI IOUT = 0, inhibit (pin 1) tied to input return (pin 7) IOUT = 0, inhibit (pin 1) = open IOUT = 1200 mA (main) IOUT = ±66.7 mA (dual) BW = DC to 2 MHz POUT = Full load TC = 25°C Over Temp TC = +25°C TC = ±25°C TC = +25°C Units mV p-p W W W W 25 mV ±35 ±75 50 mV mV mV ±75 mV 15 mA 50 50 mA mA p-p 68 % 100 MΩ TC = +25°C 500 8 6 600 W W KHz 9 13 V Notes: 1. Tested at each output. 2. Parameter guaranteed by line and load regulation tests. 3. At least 20 percent of the total output power should be taken from the (+5 volt) main output. 4. Bandwidth guaranteed by design. Tested for 20 KHz to 2 MHz. 5. An overload is that condition with a load in excess of the rated load but less than that necessary to trigger the short circuit protection and is the condition of maximum power dissipation. 6. Above 125°C case temperature, derate output power linearly to 0 at 135°C case. 7. TCASE = -55°C to 85°C for non screened grade. 2 BLOCK DIAGRAM 2 REGULATOR & OUTPUT FILTER INPUT FILTER 8 4 OUTPUT FILTER 1 5 CONTROLLER ERROR AMP & REF 6 7 3 APPLICATION INFORMATION Inhibit Function Connecting the inhibit input (Pin 1) to input common (Pin 7) will cause the converter to shut down. It is recommended that the inhibit pin be driven by an open collector device capable of sinking at least 400µA of current. The open circuit voltage of the inhibit input is 11.5 + 1 VDC. MECHANICAL OUTLINE 0.03 DIA. 8 Pins (0.76) 0.205 (5.21) 0.505 (12.83) 0.705 (17.91) 0.905 (22.99) 1 8 2 3 7 1.105 (28.07) 1.450 (36.83) 4 5 6 0.09 R Typ (2.29) 0.800 (20.32) 1.120 (28.45) 0.330 (8.38) MAX 0.26 (6.60) Tolerances: .xx = ±0.010, .xxx = ±0.005 PIN DESIGNATION 1 Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 AHF2815T Inhibit input Pin 8 Positive input Positive output Output common Pin 7 Input common Negative output +5V output Pin 6 Case Ground 8 2 3 TOP VIEW 7 4 5 3 6 Thermal Management Assuming that there is no forced air flow, the package termperature rise above ambient (ÐT) may be calculated using the following expression: ÐT ♠ 80 A PART NUMBER AHF 28 xx T / x Model -0.7 p 0. 85 ( °C) Input Voltage where A = the effective surface area in square inches (including heat sink if used;) P = power dissipation in watts. The total surface area of the AHF package is 4.9 square inches. If a worse case full load efficiency of 75% is assumed, then the case temperature rise can be calculated as follows: 1 P = POUT E - 1 FF [ ] 1 = 8 .78 - 1 [ Output Voltage 15—15 VDC Screening No Suffix ,ES, HB, CH, Triple Output (Class B compliant See table for standard military drawing number) ] = 2.66 W ÐT = 80 (4.9)-0.7 (2.66)0.85 = 60.4°C Hence, if TAMBIENT = +25°C, the DC/DC converter case temperature will be approximately 85°C if no heat sink or air flow is provided. Available Screening Levels and Process Variations for AHF Series Requirement MIL-STD-883 method Temperature Range Element Evaluation Internal Visual Temperature Cycle Constant Acceleration Burn-in Final Electrical (Group A) Seal, Fine & Gross External Visual 2017 1010 2001 1015 MIL-H-38534 & Specification 1014 2009 No Suffix ES Suffix HB Suffix -25°C to +85°C -55°C to +125°C -55°C to +125°C ◆ 25°C ✔ Cond B 500g 96hrs @125°C 25°C Cond A ◆ Cond A, C ✔ CH Suffix -55°C to +125°C MIL-H-38534 ✔ ✔ Cond C Cond C Cond A Cond A 160hrs @125°C 160hrs @125°C -55, +25, +125°C -55,+25, +125°C Cond A, C ✔ Cond A, C ✔ ◆ per Commercial Standards © Lambda Advanced Analog The information in this data sheet has been carefully checked and is believed to be accurate, however, no responsibility is assumed for possible errors. The specifications are subject to change without notice. 9848 2270 Martin Avenue MIL-PRF-38534 Certified Santa Clara CA 95050-2781 ISO9001 Rgstrd (408) 988-4930 FAX (408) 988-2702