DEMO MANUAL DC1860B LT3748 No-Opto Isolated FlybacK Converter for PSE Applications Description Demonstration circuit 1860B is an isolated flyback converter featuring the LT3748. This demo circuit is designed for Power Sourcing Equipment (PSE) applications with a 52.5V output from a 10V to 15V DC input, with nominal input voltage of 12V. The output current is from 0mA to 700mA, and is capable of a maximum short period overload current of 900mA. Table 1 summarizes the performance of the demo board. This demo circuit can also be easily modified for different PSE applications with some predesigned transformers. The LT3748 is a high input voltage isolated flyback controller operating with input supply voltages from 5V to 100V, and 1.9A average gate drive source and sink current. The LT3748 utilizes boundary mode operation to provide a high PERFORMANCE SUMMARY PARAMETER efficiency, small size solution with improved regulation. The part senses the isolated output voltage directly from the primary side flyback waveform during the off time of the power switch. No third winding, opto-coupler, or signal transformer is required for regulation. The LT3748 data sheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with this quick start guide for demo circuit 1860B. Design files for this circuit board are available at http://www.linear.com/demo 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. (TA = 25°C) CONDITIONS MIN TYP MAX 10 12 15 V VIN = 10V – 15V IOUT = 0V – 700 mA 50 52.5 55 V 700 Input Voltage Range Output Voltage UNITS Maximum Output Current VIN = 10V – 15V Minimum Output Current VIN = 10V – 15V mA Output Voltage Ripple (Peak to Peak) VIN = 10V – 15V, IOUT = 0 – 700mA 150 mV Efficiency VIN = 13.2V, IOUT = 700mA 87.8 % 0 mA dc1860bfa 1 DEMO MANUAL DC1860B quick start procedure Demo circuit 1860B is easy to set up to evaluate the performance of the LT3748. Refer to Figure 1 for proper equipment setup and follow the procedure below. ex-board preload requirement. The efficiency is higher than 90% without the preload resistors, but the output may exceed 57V under no load or transient condition. 1.With power off, connect the input power supply to the board through VIN (E1) and GND (E2) terminals. 5.Once the proper output voltage is established, adjust the input voltage and load current within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters. 2. Connect the load to the terminals VOUT+ (E6) and VOUT– (E7) on the board. 3.Turn on the power at the input. Increase VIN slowly to 10V. NOTE: Make sure that the input voltage does not exceed 15V. If higher operating voltage is required, power components with higher voltage ratings should be used. 4. Check for the proper output voltages. The output should be regulated at 52.5V (±5%). NOTE: The LT3748 requires minimum load to maintain good output voltage regulation. A zener diode D1 together with preload resistors R2, R14, R15 and R16 are placed in the output to clamp the output voltage to ~52.5V without 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 terminals of the input or output capacitor. See Figure 2 for proper scope probe technique. NOTE: A gate resistor of less than 10Ω can be added to the demo circuit to slow down the turning off of the switch, and reduce the switching node voltage spike. A RC snubber can be added as well to the primary winding of the transformer to damp the spike and reduce the EMI. dc1860bfa 2 DEMO MANUAL DC1860B quick start procedure Figure 1. Proper Measurement Equipment Setup + VOUT – COUT GND dc1860b F02 Figure 2. Proper Scope Probe Placement for Measuring Input or Output Ripple dc1860bfa 3 DEMO MANUAL DC1860B quick start procedure 100 90 EFFICIENCY (%) 80 70 60 50 40 30 20 VIN = 10V VIN = 13.2V VIN = 15V 10 0 0 100 200 300 400 500 600 700 LOAD CURRENT (mA) dc1860b F03 Figure 3. Typical Efficiency Curve, (TA = 25°C) 53.0 Output Voltage (V) 52.5 52.0 51.5 51.0 50.5 50.0 VIN = 15V VIN = 10V 0 100 200 300 400 500 600 700 LOAD CURRENT (mA) dc1860b F04 Figure 4. Load Regulation VOUT: 20V/DIV VDS: 20V/DIV Figure 5. Recovery from Short Circuit Fault dc1860bfa 4 DEMO MANUAL DC1860B parts list ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Cap., X5R, 22µF, 16V, 20%, 1210 Taiyo Yuden EMK325BJ226MN Required Circuit Components 1 2 C2, C3 2 1 C5 Cap., X7S, 0.22µF, 100V, 10%, 0805 TDK C2012X7S2A224KT 3 3 C6, C7, C8 Cap., X7S, 4.7µF, 100V, 20%, 1812 TDK C4532X7S2A475MT 4 1 C9 Cap., Elect. 470µF, 63V, 20%, J16-PANASONIC PANASONIC EEVFK1J471M 5 1 C10 Cap., X5R, 4.7µF, 16V, 20%, 0805 Taiyo Yuden EMK212BJ475MG 6 1 C11 Cap., X5R, 0.33µF, 10V, 20%, 0603 AVX 0603ZD334MAT1A 7 1 C12 Cap., NPO, 470pF, 25V, 10%, 0603 AVX 06033A471KAT2A 8 1 C13 Cap., Ceramic 2.2nF, 250V, 10%, 1812 Murata GA343QR7GD222KW01L 9 2 C14, C15 Cap,, X7R, 6800pF, 25V, 20%, 0603 AVX 06033C682MAT2A 10 1 D1 Diode Zener 62V ON Semi. 1SMB5943BT3 11 1 D2 Schottky Diode 1A/100V, PowerDItm123 Diodes Inc. DFLS1100 12 1 D3 Schottky Diode 3A, PowerDi5 Diodes Inc. PDS3200-13 13 1 L1 Inductor, 1.8µH Würth Electronik 744318180 14 1 Q1 Mosfet N-Channel, 100V, LFPAK Renesas HAT2173H-EL-E 15 2 R1, R13 Res., Chip, 16k, 0.25W, 5%, 1206 Vishay CRCW120616K0JNED 16 4 R2, R14, R15, R16 Res., Chip, 11.8k, 0.25W, 1%, 1206 Vishay CRCW120611K8FKEA 17 2 R3, R7 Res/Jumper, Chip, 0Ω, 1/16W, 1 AMP 0603 Vishay CRCW06030000Z0EA 18 1 R4 Res., Chip, 200k, 0.06W, 1%, 0603 Vishay CRCW0603200KFKEA 19 1 R5 Res., Chip, 36k, 0.06W, 5%, 0603 Vishay CRCW060336K0JNEA 20 1 R6 Res., Chip, 82.5k, 0.06W, 1%, 0603 Vishay CRCW060382K5FKEA 21 1 R8 Res., Chip, 22, 0.06W, 5%, 0603 Vishay CRCW060322R0JNEA 22 1 R9 Res., Chip, 270k, 0.06W, 5%, 0603 Vishay CRCW0603270KJNEA 23 1 R10 Res., Chip, 40.2k, 0.06W, 1%, 0603 Vishay CRCW060340K2FKEA 24 1 R11 Res., Chip, 6.04k, 0.06W, 1%, 0603 Vishay CRCW06036K04FKEA 25 1 R12 Res., 0.005, 0.25W, 1%, 1206 Vishay Dale WSL-1206-5L000-1% 26 1 T1 Transformer, XFMR Würth Elektronik 750311591 27 1 U1 I.C., LT3748EMS Linear Tech. Corp. LT3748EMS Connector, Banana Jack Keystone 575-4 Hardware For Demo Board Only 1 2 E1, E2 2 3 E5, E6, E7 Turret, Testpoint Mill Max 2501-2-00-80-00-00-07-0 3 1 JP1 Headers, Sgl. Row, 3 Pins, 2mm Ctrs. Samtec TMM-103-02-L-S 4 4 MH1, MH2, MH3, MH4 STAND-OFF, NYLON 0.25" tall KEYSTONE, 8831(SNAP ON) 5 1 XJP1 Samtec 2SN-BK-G Shunt, 2mm Ctrs. 6 1 FAB, 1860B, Rev 3.PCB DEMO CIRCUIT 1860B 7 2 STENCILS - TOP & BOTTOM STENCIL DC1860B Additional Demo Board Circuit Components 1 0 C1 (Opt) Cap., Alum 330µ,F 25V, 10%, 25cv330gX 2 0 C16 (Opt) Cap., Alum. Elect. 100µF, 63V, ±20%, NipponChemi-Con/JA0 Nippon Chemi-Con EMZA630ADA101MJA0G SANYO 25CV330gX 3 0 L2 (Opt) Inductor, 47µH, IHLP4040 VISHAY IHLP-4040DZ-ER-470-M11 4 0 T2 (Opt) Transformer, XFMR Würth Elektronik 750311456 5 0 T3 (Opt) Transformer, XFMR Würth Elektronik 750311604 6 0 E3, E4 (Opt) Turret, Testpoint Mill Max 2501-2-00-80-00-00-07-0 dc1860bfa 5 6 1 2 3 4 JP1 C11 0.33uF SHDN RUN E5 E2 E1 3 2 SHDN 1 EXT_EN GND VIN 10V-15V + A VIN C12 470pF C15 6800pF R10 40.2k 1% R4 200k 1% R5 36k C1 330uF 25V SANYO (Opt) R9 270k A R11 6.04k 1% 14 11 12 10 3 C2 22uF 16V 1210 VIN 1 REF VC TC SS 8 9 GND GND B SENSE GATE RFB INTVCC U1 LT3748EMS EN/UVLO C3 22uF 16V 1210 B 7 6 16 5 R1 16k 1206 22 C14 6800pF R8 0 Ohm 82.5k 1% R7 D2 C10 DFLS1100 4.7uF 16V 0805 R6 R3 0 Ohm C5 0.22uF 100V 0805 5 11 C13 CUSTOMER NOTICE 2.2nF 250V 1812 1 2 PDS3200-13 3 D3 C6 4.7uF 100V 1812 C THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. C:\PADS PROJECTS\1860B\REV_B(09-17-12)\SCH\1860B_REV1.DSN LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. R12 0.005 1206 1 750311591 12 3 DIODE 6 9 2 4 8 T1 10 7 Q1 HAT2173H-EL-E Renesas R13 16k 1206 SW C 1 SCALE = NONE APP ENG. ZHONGMING Y. PCB DES. DATE: SIZE D + VOUT- VOUT+ [email protected] E4 VOPT(Opt) C9 470uF 63V E7 E6 IC NO. E SHEET 1 OF 2 1 REV. TITLE: SCHEMATIC R16 11.8k 1% 1206 E3 VOPT+ [email protected] (Opt) www.linear.com R15 11.8k 1% 1206 VOUT+ DATE Oct 01, 2012 R14 11.8k 1% 1206 TECHNOLOGY R2 11.8k 1% 1206 L1 1.8uH 744318180 Wurth Electronik E ZHONGMING Y. REVISION HISTORY APPROVED DESCRIPTION PRODUCTION VOPT D D1 1SMB5943BT3 C8 4.7uF 100V 1812 APPROVALS C7 4.7uF 100V 1812 ECO REV 1 2 3 4 DEMO MANUAL DC1860B Schematic Diagram dc1860bfa 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. 1 2 3 4 A A SW 1 2 5 3 12 1 750311604 (Opt) 9 11 8 3 5 6 2 4 T3 750311456 (Opt) 9 10 6 7 T2 VOPT DIODE APPROVALS C B THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. C:\PADS PROJECTS\1860B\REV_B(09-17-12)\SCH\1860B_REV1.DSN C SCALE = NONE L2 D DATE: SIZE IC NO. D E SHEET 2 OF 1 2 REV. SCHEMATIC TECHNOLOGY E www.linear.com C16 100uF 63V (Opt) VOUT+ 47uH IHLP-4040DZ-ER-470-M11 VISHAY (Opt) VOPT LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APP ENG. ZHONGMING Y. TITLE: APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. CUSTOMER NOTICE Optional Circuit VIN B 1 2 3 4 DEMO MANUAL DC1860B Schematic Diagram dc1860bfa 7 DEMO MANUAL DC1860B 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 dc1860bfa 8 Linear Technology Corporation LT 0213 REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2011