DEMO MANUAL DC2324A LT3753 Active Clamp Forward Converter with Synchronous Rectification Description Demonstration circuits 2324A-A, 2324A-B, and 2324A-C are active clamp forward converters with synchronous rectification featuring the LT®3753. The DC2324A circuits feature soft-start which prevents output voltage overshoot during startup or when recovering from an overload condition. These circuits were designed to demonstrate the high level of performance, efficiency and small solution size attainable using this part. They operate at 240kHz. The DC2324A-A produces a 24V/5A output from an input voltage range of 36V to 72V. The DC2324A-B produces a 24V/5A output from an input voltage range of 18V to 36V. The DC2324A-C produces a 24V/4A output from an input voltage range of 9V to 18V, making it suitable for telecom, industrial and other isolated power supply applications. They all have an eighth-brick footprint area. Synchronous rectification helps to attain efficiency exceeding 94% (exceeding 95% for the DC2324A-A and DC2324A-B). The DC2324A also has a precise overcurrent protection circuit that allows for continuous operation and low power dissipation during short circuit conditions which ensures high reliability. Please refer to the LT3753 data sheet for design details and applications information. Design files for this circuit board are available at http://www.linear.com/demo/DC2324A L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Performance Summary DC2324A-A SYMBOL PARAMETER VIN Input Supply Range Specifications are at TA = 25°C CONDITIONS MIN TYP 36 VOUT Output Voltage IOUT Maximum Output Current, Continuous 21.6 fSW Switching (Clock) Frequency VOUT P-P Output Ripple VIN = 48V, IOUT = 5A (20MHz BW) POUT/PIN Efficiency (see Figure 2) VIN = 48V, IOUT = 5A 24 MAX 72 V 26.4 V 5 Performance Summary DC2324A-B UNITS A 240 kHz 40 mVP–P 95.6 % Specifications are at TA = 25°C SYMBOL PARAMETER CONDITIONS VIN Input Supply Range VOUT Output Voltage IOUT Maximum Output Current, Continuous fSW Switching (Clock) Frequency VOUT P-P Output Ripple VIN = 48V, IOUT = 5A (20MHz BW) POUT/PIN Efficiency (see Figure 3) VIN = 48V, IOUT = 5A MIN TYP MAX 36 V 24 26.4 V 18 21.6 5 UNITS A 240 kHz 30 mVP–P 95.7 % dc2324af 1 DEMO MANUAL DC2324A Performance Summary DC2324A-C SYMBOL PARAMETER VIN Input Supply Range Specifications are at TA = 25°C CONDITIONS MIN TYP 9 VOUT Output Voltage IOUT Maximum Output Current, Continuous 21.6 fSW Switching (Clock) Frequency VOUT P-P Output Ripple VIN = 48V, IOUT = 5A (20MHz BW) POUT/PIN Efficiency (see Figure 4) VIN = 48V, IOUT = 5A 24 4 MAX UNITS 18 V 26.4 V A 240 kHz 30 mVP–P 94.8 % Quick Start Procedure Demonstration circuit 2324A is easy to set up to evaluate the performance of the LT3753. Refer to Figure 1 for proper measurement equipment setup and follow the procedure below: 5. Once the proper output voltage is established, connect a variable load capable of sinking 5A at 24V to the output terminals +VOUT and –VOUT. Set the current for 0A. 1. Set an input power supply that is capable of covering the input voltage range of the DC2324A (see the Performance Summary table) to one of these voltages: a. If efficiency measurements are desired, an ammeter that is capable of handling 5ADC can be put in series with the output load in order to measure the DC2324A’s output current. 48V for the DC2324A-A, 12V for the DC2324A-C. b. A voltmeter can be placed across the output terminals in order to get an accurate output voltage measurement. 6. Turn on the power at the input. 24V for the DC2324A-B, Then turn off the supply. 2. With power off, connect the supply to the input terminals +VIN and –VIN. If efficiency measurements are desired, an ammeter with proper rating can be put in series with the input supply in order to measure the DC2324A’s input current. 3. Turn on the power at the input. NOTE: Make sure that the input voltage does not exceed 100V. 4. Check for the proper output voltage of 24V. Turn off the power at the input. 2 NOTE: If there is no output, temporarily disconnect the load to make sure that the load is not set too high. 7. Once the proper output voltage is again established, adjust the load within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other desired parameters. NOTE: When measuring the input or output voltage ripples, care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the input or output voltage ripple by touching the probe tip directly across the +VIN and –VIN, or +VOUT and –VOUT terminals. dc2324af DEMO MANUAL DC2324A Quick Start Procedure + VIN – – + – IIN + VIN LOAD + – IOUT + VOUT – + – DC2324 F01 100 100 95 95 95 90 85 80 75 1 2 3 LOAD CURRENT (A) 4 5 DC2324 F02 Figure 2. DC2324A-A Efficiency 90 85 80 VIN = 36V VIN = 48V VIN = 72V 0 EFFICIENCY (%) 100 EFFICIENCY (%) EFFICIENCY (%) Figure 1. Proper Measurement Equipment Setup 75 1 2 3 LOAD CURRENT (A) 4 5 DC2324 F03 Figure 3. DC2324A-B Efficiency 85 80 VIN = 18V VIN = 24V VIN = 36V 0 90 75 VIN = 9V VIN = 12V VIN = 18V 0 1 2 3 LOAD CURRENT (A) 4 5 DC2324 F04 Figure 4. DC2324A-C Efficiency dc2324af 3 DEMO MANUAL DC2324A Quick Start Procedure 20mV/DIV 2µs/DIV DC2324 F05 Figure 5. DC2324A-A Output Ripple at 48VIN and 5AOUT (20MHz BW) 20mV/DIV 2µs/DIV DC2324 F06 Figure 6. DC2324A-B Output Ripple at 24VIN and 5AOUT (20MHz BW) 20mV/DIV 2µs/DIV DC2324 F07 Figure 7. DC2324A-C Output Ripple at 12VIN and 4AOUT (20MHz BW) 4 dc2324af DEMO MANUAL DC2324A Quick Start Procedure Figure 8. DC2324A-A Thermal Map, Front Side at 48VIN and 5AOUT (TA = 25°C) Figure 9. DC2324A-A Thermal Map, Back Side at 48VIN and 5AOUT (TA = 25°C) Figure 10. DC2324A-B Thermal Map, Front Side at 24VIN and 5AOUT (TA = 25°C) dc2324af 5 DEMO MANUAL DC2324A Quick Start Procedure Figure 11. DC2324A-B Thermal Map, Back Side at 24VIN and 5AOUT (TA = 25°C) Figure 12. DC2324A-C Thermal Map, Front Side at 12VIN and 4AOUT (TA = 25°C) Figure 13. DC2324A-C Thermal Map, Back Side at 12VIN and 4AOUT (TA = 25°C) 6 dc2324af DEMO MANUAL DC2324A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components for DC2324A-A, DC2324A-B, and DC2324A-C 1 1 CO1 CAP., X7R, 10µF, 50V, 10% 1210 MURATA, GRM32ER71H106KA12L 2 1 CSYS CAP., ALUM., 270µF, 35V, G size PANASONIC, EEHZA1V271P 3 1 CY1 CAP., X7R, 2200pF, 250V, 10% 2220 MURATA, GA355QR7GF222KW01L 4 3 C1, C3, C5 CAP., X7R, 0.1µF, 50V, 10% 0603 MURATA, GRM188R71H104KA93D 5 1 C2 CAP., X7R, 4.7µF, 25V, 10% 0805 MURATA, GRM21BR71E475KA73L 6 1 C4 CAP., X7S, 1µF, 100V, 10% 0805 MURATA, GRJ21BC72A105KE11L 7 1 C7 CAP., X7R, 2.2nF, 250V, 10% 0805 MURATA, GRM21AR72E222KW01D 8 1 C9 CAP., C0G, 680pF, 50V, 5% 0603 WURTH ELEKTRONIK, 885012006062 9 1 D1 DIODE, CMMR1U-02 SOD-123F CENTRAL SEMI., CMMR1U-02 10 2 D2, D3 DIODE, BAV21W, SOD-123 MICRO COMMERCIAL CO., BAV21W-TP 11 1 D4 DIODE, BAT54A, SOT23 DIODES., BAT54A-7-F 12 1 D5 DIODE, HIGH-SPEED DIODE, SOD-523 NXP/PHILLIPS SEMI., BAS516 13 1 L1 INDUCTOR, 39µH, CHAMPS, HRPQA2050-39 14 2 Q3, Q4 N-MOSFET, POWER 56 FAIRCHILD, FDMS86200DC 15 1 R1 RES., CHIP, 31.6k, 0.1W, 1% 0603 VISHAY, CRCW060331K6FKEA 16 1 R2 RES., CHIP, 100k, 0.1W, 1% 0603 VISHAY, CRCW0603100KFKEA 17 1 R6 RES., CHIP, 61.9k, 0.1W, 1% 0603 VISHAY, CRCW060361K9FKEA 18 1 R9 RES., CHIP, 200k, 0.125W, 1% 0805 VISHAY, CRCW0805200KFKEA 19 1 R14 RES., CHIP, 15Ω, 0.1W, 1% 0603 VISHAY, CRCW060315R0FKEA 20 1 R3 RES., CHIP, 10k, 0.1W, 1% 0603 VISHAY, CRCW060310K0FKEA 21 2 R4, R10 RES., CHIP, 10Ω, 0.1W, 1% 0603 VISHAY, CRCW060310R0FKEA 22 1 R11 RES., CHIP, 20k, 3/4W, 1% 2010 VISHAY, CRCW201020K0FKEF 23 2 R12, R13 RES., CHIP, 100Ω, 0.1W, 1% 0603 VISHAY, CRCW0603100RFKEA 24 1 U1 I.C., LT3753EFE#TRPBF, TSSOP-38(31) LINEAR TECH., LT3753EFE#TRPBF DC2324A-A Required Circuit Components 25 4 CIN1–CIN4 CAP., X7S, 4.7µF, 100V, 10% 1210 MURATA, GRJ32DC72A475KE11L 26 1 C6 CAP., X7R, 47nF, 250V, 10% 1206 MURATA, GRM31CR72E473KW03L 27 1 Q1 N-MOSFET POWER-56 FAIRCHILD, FDMS86200DC 28 1 Q2 P-MOSFET POWER-33 VISHAY, Si7117DN-T1-E3 29 1 RCS1 RES., CHIP, 0.011Ω, 1W, 1%, WIDE 1206 SUSUMU, PRL1632-R011-F-T5 30 1 R5 RES., CHIP, 28k, 0.1W, 1% 0603 VISHAY, CRCW060328K0FKEA 31 1 R7 RES., CHIP, 3.48k, 0.1W, 1% 0603 VISHAY, CRCW06033K48FKEA 32 1 R8 RES., CHIP, 4.22k, 0.1W, 1% 0603 VISHAY, CRCW06034K22FKEA 33 1 T1 TRANSFORMER, CHAMPS, G45R2-0808-S01-80R DC2324A-B Required Circuit Components 25 4 CIN1-CIN4 CAP., X7R, 10µF, 50V, 10% 1210 MURATA, GRM32ER71H106KA12L 26 1 C6 CAP., X7R, 150nF, 250V, 10% 1210 MURATA, GRM32QR72E154KW01L 27 1 Q1 N-MOSFET POWER-56 FAIRCHILD, FDMS86101DC 28 1 Q2 P-MOSFET SOT23 VISHAY, Si2337DS-T1-GE3 29 1 RCS1 RES., CHIP, 0.005Ω, 1W, 1%, 0815 SUSUMU, RL3720WT-R005-F 30 1 R5 RES., CHIP, 40.2k, 0.1W, 1% 0603 VISHAY, CRCW060340K2FKEA dc2324af 7 DEMO MANUAL DC2324A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER 31 32 1 R7 RES., CHIP, 7.32k, 0.1W, 1% 0603 VISHAY, CRCW06037K32FKEA 1 R8 RES., CHIP, 8.66k, 0.1W, 1% 0603 VISHAY, CRCW06038K66FKEA 33 1 T1 TRANSFORMER, CHAMPS, G45R2-0408-S01-25R DC2324A-C Required Circuit Components 25 4 CIN1-CIN4 CAP., X7R, 22µF, 25V, 10% 1210 MURATA, GRM32ER71E226KE15L 26 1 C6 CAP., X7R, 330nF, 250V, 10% 1812 MURATA, GRM43DR72E334KW01L 27 1 Q1 N-MOSFET PG-TDSON INFINEON, BSC010N04LSATMA1 28 1 Q2 P-MOSFET SC-70 VISHAY, SQ1421EEH-T1-GE3 29 1 RCS1 RES., CHIP, 0.003Ω, 1W, 1%, 0815 SUSUMU, RL3720WT-R003-F 30 1 R5 RES., CHIP, 40.2k, 0.1W, 1% 0603 VISHAY, CRCW060340K2FKEA 31 1 R7 RES., CHIP, 16.2k, 0.1W, 1% 0603 VISHAY, CRCW060316K2FKEA 32 1 R8 RES., CHIP, 19.6k, 0.1W, 1% 0603 VISHAY, CRCW060319K6FKEA 33 1 T1 TRANSFORMER, CHAMPS, G45R2-0208-S01-8R0 Additional Demo Board Circuit Components for All Versions 1 0 CO2(OPT) CAP., 1210 2 0 C8(OPT) CAP., 100V, SIZE 12X10 Hardware: For Demo Board Only (All Versions) 1 2 E1, E2 TESTPOINT, TURRET, 0.061" PBF MILL-MAX, 2308-2-00-80-00-00-07-0 2 4 E3, E4, E5, E6 TESTPOINT, TURRET, 0.094" PBF MILL-MAX, 2501-2-00-80-00-00-07-0 3 4 J1-J4 BANANA JACK KEYSTONE, 575-4 4 4 MH1-MH4 STAND-OFF, NYLON 9.5mm WURTH ELEKTRONIK, 702933000 8 dc2324af Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. A B C D -VIN * E4 J2 J1 C8 OPT + E2 GND SGND INTVCC SYNC TBLNK TOS TAS TAO IVSEC OVLO UVLO_VSEC 250V 2220 CY1 2200pF 5 EVAL1: EFE PACKAGE (FE38 (31) ) BOARD SIZE: 2.30 BY 1.45 U1 LT3753EFE R1 C1 31.6K 0.1uF C2 4.7uF 25V 0805 26 6 100K 14 13 12 11 8 10 9 C4 1uF 100V 0805 X7S 61.9K 0805 INTVCC R2 R5 * * R7 R6 * R8 R9 200K R14 15 28 NOTE: UNLESS OTHERWISE SPECIFIED: ALL RESISTORS & CAPACITORS ARE 0603 . ALL RESISTORS ARE 1% RESISTORS. ALL CERAMIC CAPACITORS ARE X7R E1 SYNC * CIN1 CIN2 CIN3 CIN4 1210 37 VIN 34 NC E3 SS1 7 RT 3 36 NC 1 TEST2 2 TEST1 GND 18 4 4 0.1uF C3 5 30 32 20 16 15 21 22 24 * R12 100 24V / 5A 24V / 4A 18V - 36V 9V - 18V 24V / 5A 36V - 72V -C +VOUT -B +VIN FOR ASSEMBLY C5 0.1uF C9 680pF C0G R13 100 Q1 -A VERSIONS COMP SOUT AOUT ISENSEN NC NC ISENSEP OC OUT PGND PGND 38 39 NC SS2 17 FB 4 PGND 19 +VIN 5 * CIN1 - CIN4 D5 BAS516 R3 10K RCS1 22uF / 25V 10uF / 50V 3 4.7uF / 100V,X7S * 3 * C6 330nF / 1812 150nF / 1210 47nF / 1206 Q2 C6 250V 12 11 7 5 * 8 * T1 2 40.2K 40.2K 28K R5 16.2K 7.32K 3.48K R7 BAT54A-7-F D4 FSW CSW 19.6K 8.66K 4.22K R8 10 R10 CSW FSW 2 Si2337DS SQ1421EEH Si7117DN BSC010N04LS FDMS86101DC 3m / 0815 FDMS86200DC Q2 20K 2010 R11 5m / 0815 Q1 BAV21W-TP D3 C7 2.2nF 250V 0805 D1 CMMR1U-02 T1 CO1 10uF 50V 1210 CO2 1210 OPT G45R2-0208-S01-8R0 G45R2-0408-S01-25R G45R2-0808-S01-80R L1 39uH HRPQA2050-39 11m / Wide 1206 RCS1 10 R4 BAV21W-TP D2 Q3 FDMS86200DC Q4 FDMS86200DC 2 1 1 J3 E5 E6 J4 CSYS + 270uF 35V EEHZA1V271P +VO1 -VOUT * +VOUT A B C D DEMO MANUAL DC2324A Schematic Diagram dc2324af 9 DEMO MANUAL DC2324A DEMONSTRATION BOARD IMPORTANT NOTICE Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions: This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations. If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES. The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive. Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and observe good laboratory practice standards. Common sense is encouraged. This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer. Mailing Address: Linear Technology 1630 McCarthy Blvd. Milpitas, CA 95035 Copyright © 2004, Linear Technology Corporation 10 Linear Technology Corporation dc2324af LT 0516 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2016