DEMO MANUAL DC1228A LT3573 Isolated Monolithic Flyback Converter Description Demonstration circuit 1228A is an isolated flyback converter featuring the LT®3573. This demo circuit is designed for a 5.0V output from a 10V to 30V input. The maximum output current is 1A when the input voltage is higher than 20V. No third winding or opto-isolator is required for regulation. The part senses the isolated output voltage directly from the primary-side flyback waveform. with improved load regulation. The LT3573 can be used in industrial, automotive and medical applications where an isolated output is required. The LT3573 operates with input supply voltages from 3V to 40V, and can deliver an output power up to 7W with no external power devices. The LT3573 utilizes boundary mode operation to provide a small magnetic solution Design files for this circuit board are available at http://www.linear.com/demo/DC1228A Performance Summary PARAMETER The LT3573 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 demonstration circuit 1228A. 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. Specifications are at TA = 25°C CONDITION Input Voltage Range MIN TYP 10 5 MAX UNITS 30 V 5.25 V Output Voltage VOUT VIN = 10V to 30V 4.75 Maximum Output Current IOUT VIN = 10V to 20V VIN = 20V to 30V 0.7 1.0 Switching Frequency VIN = 12V, IOUT = 0.7A VIN = 24V, IOUT = 1A 169 238 kHz kHz Voltage Ripple VOUT VIN = 24V, IOUT = 1A 100 mV Efficiency VIN = 24V, IOUT = 1A 84 % A A dc1228af 1 DEMO MANUAL DC1228A Quick Start Procedure Demonstration circuit 1228A is easy to set up to evaluate the performance of the LT3573. Refer to Figure 1 for proper measurement equipment setup and follow the procedure below: NOTE: When measuring the input or output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. See Figure 2 for proper scope probe technique. 1.With power off, connect the input power supply to VIN and GND. 2.Turn on the power at the input. NOTE: Make sure that the input voltage does not exceed 30V. 3.Check for the proper output voltages. NOTE: If there is no output, temporarily disconnect the load to make sure that the load current is not set too high. 4.Once the proper output voltage is established, adjust the load current within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters. 2 dc1228af DEMO MANUAL DC1228A Quick Start Procedure Figure 1. Proper Measurement Equipment Setup VIN OR VOUT GND Figure 2. Measuring Input or Output Ripple dc1228af 3 DEMO MANUAL DC1228A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 1 C2 CAP., X7R, 4.7µF 50V, 1210 MURATA, GRM32ER71H475K 2 1 C4 CAP., X7R, 47µF 10V, 1210 MURATA, GRM32ER71A476K 3 1 C7 CAP., X7R, 0.1µF 16V, 0402 TDK, C1005X7R1C104MT 4 1 C8 CAP., NPO, 100pF 50V,0402 AVX, 04025A101JAT2A 5 2 C12, C9 CAP., X7R, 1µF 50V, 0805 MURATA, GRM21BR71H105K 6 1 C10 CAP., X7R, 0.22µF 25V, 0603 MURATE, GRM188R71E224K 7 1 C11 CAP., X7R, 4700pF 25V, 0402 AVX, 04023C472KAT2A 8 1 C13 CAP., NPO, 10pF 50V, 0402 AVX, 04025A100JAT2A 9 1 D1 DIODE, SCHOTTKY BARRIER RECTIFIER 3.0A DIODES INC., B340A-13-F 10 1 D2 DIODE, SWITCHING, SOD323 DIODES INC., 1N4148WS-7-F 11 1 D3 DIODE, SCHOTTKY MINI, SOD323 CENTRAL SEMI., CMDSH-3 12 1 R3 RES., CHIP 357k 1/16W 1%, 0402 VISHAY, CRCW0402357KFKED 13 1 R6 RES., CHIP 93.1k 1/16W 1%, 0402 VISHAY, CRCW040293K1FKED 14 1 R7 RES., CHIP 84.5k 1/16W 1%, 0402 VISHAY, CRCW040284K5FKED 15 1 R8 RES., CHIP 2k 1/10W 1%, 0805 VISHAY, CRCW08052K00FKEA 16 1 R9 RES., CHIP 20k 1/16W 1%, 0402 VISHAY, CRCW040220K0FKED 17 1 R10 RES., CHIP 10k 1/16W 1%, 0402 VISHAY, CRCW040210K0FKED 18 1 R11 RES., CHIP 6.04k 1/16W 1%, 0402 VISHAY, CRCW04026K04FKED 19 1 R15 RES., CHIP 12.4k 1/16W 1%, 0402 VISHAY, CRCW040212K4FKED 20 1 T1 XFMR, 750370047 WÜRTH, 750370047 21 1 U1 IC., LT3573EMSE, MSE16 LINEAR TECH., LT3573EMSE Additional Demo Board Circuit Components 1 1 C1 CAP., ELECTROLYTIC, 22µF 50V, C-SANYO-CE-BS-6.3X6.0 SANYO, 50CE22BS 2 0 C5 CAP., 22µF 50V, C-SANYO-CE-BS-6.3X6.0 OPT SANYO, 50CE22BS 3 0 C14 CAP., 1206 OPT OPT 4 0 C19 CAP., X7R, 4.7µF 50V, 1210 OPT MURATA, GRM32ER71H475K 5 0 C20 CAP., X7R, 0.01µF 50V, 0603 OPT AVX, 06035C103KAT 6 0 FB1 BEAD, 1206 OPT TAIYO YUDEN, FB MJ3216HS800 7 0 L1 IND, PWR, L-CDRH4D22/HP OPT SUMIDA, CDRH4D22HPNP-100MC 8 0 R2 RES., 0603 OPT OPT 9 1 R4 RES., CHIP 499Ω 1/10W 1%, 0805 VISHAY, CRCW0805499RFKEA TP, TURRET, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0 Hardware: For Demo Board Only 1 4 5 E1, E2, E3, E5, E6 dc1228af 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 + 5 4 D 4 3 + 1 2 1 TECHNOLOGY 2 3 5 A B C D DEMO MANUAL DC1228A Schematic Diagram dc1228af 5 DEMO MANUAL DC1228A 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 6 dc1228af Linear Technology Corporation LT 0913 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2013