DEMO MANUAL DC1963A LT8310 48VIN to 12V/6A Isolated Forward Converter Description Demonstration circuit 1963A is a resonant reset forward converter featuring the LT®8310 controller. This circuit was designed to demonstrate the high level of performance, and small solution size attainable using the LT8310. It operates at a 250kHz switching frequency, and regulates a 12V, 6A output from a 36V to 72V input source, making it well suited for telecom, industrial, and other applications. Table 1 summarizes the performance of the DC1963A. The LT8310 is a constant-frequency forward converter controller with a low side N-channel MOSFET gate driver. Output regulation is handled on the secondary side by the LT1431, which is an adjustable shunt voltage regulator providing feedback to the primary side via an opto-coupler. The DC1963A takes advantage of the LT8310’s input undervoltage and overvoltage protection to shutdown the system when the input voltage is outside of the set limits. The DC1963A also has precise overcurrent protection that allows for continuous operation under short circuit conditions. The low power dissipation under a short circuit condition ensures high reliability even during a prolonged output voltage short circuit. The LT8310 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 1963A. Design files for this circuit board are available at http://www.linear.com/demo/DC1963A 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 PARAMETER Specifications are at TA = 25°C CONDITIONS Input Voltage Output Voltage VIN = 36V – 72V Maximum Output Current MIN TYP MAX 36 48 72 V 11.76 12 12.24 V 6 Switching (Clock) Frequency Output Voltage Ripple (Peak-to-Peak) VIN = 36V – 72V, IOUT = 6A (20MHz BW) Output Regulation Line and Load (36V to 72VIN, 0A to 6AOUT) Efficiency (See Figure 3) UNITS A 250 kHz 50 mV ±0.1 % VIN = 36V, IOUT = 6A 91 % VIN = 48V, IOUT = 6A 91.5 % VIN = 72V, IOUT = 6A 90.5 % dc1963af 1 DEMO MANUAL DC1963A Quick Start Procedure Demonstration circuit 1963A is easy to set up to evaluate the performance of the LT8310. Refer to Figure 1 for proper measurement equipment setup and follow the procedure below: 1. With power off, connect the input power supply to the board through +VIN and –VIN terminals. Connect the load to the terminals +VOUT and –VOUT on the board. 2. Turn on the power at the input. NOTE: Make sure that the input voltage does not exceed 72V. Input voltages lower than 36V can keep the converter from turning on due to the undervoltage lockout feature of the LT8310. NOTE: If there is no output, temporarily disconnect the load to make sure that the load is not set too high. 4. 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. 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. See Figure 2 for proper scope probe technique. 3. Check for the proper output voltages. The output should be regulated at 12V (±2%). 2 dc1963af DEMO MANUAL DC1963A Quick Start Procedure POWER SUPPLY – – + VIN + + – LOAD – IIN – VOUT + + – + IOUT Figure 1. Proper Measurement Equipment Setup INPUT OR OUTPUT CAPACITOR Figure 2. Proper Scope Probe Placement for Measuring Input/Output Ripple dc1963af 3 DEMO MANUAL DC1963A performance 93 91 EFFICIENCY (%) 89 87 85 83 81 79 VIN = 36V VIN = 48V VIN = 72V 77 75 0 1 2 3 4 LOAD CURRENT (A) 5 6 Figure 3. Typical Efficiency Curve GATE VOLTAGE 10V/DIV GATE VOLTAGE 10V/DIV SWITCH NODE VOLTAGE 50V/DIV SWITCH NODE VOLTAGE 50V/DIV 1µs/DIV 1µs/DIV (4a) 36VIN to 6AOUT (4b) 48VIN to 6AOUT GATE VOLTAGE 10V/DIV SWITCH NODE VOLTAGE 50V/DIV 1µs/DIV (4c) 72VIN to 6AOUT Figure 4. Steady State Waveforms 4 dc1963af DEMO MANUAL DC1963A performance SWITCH NODE VOLTAGE OF SECONDARY DIODE 50V/DIV SWITCH NODE VOLTAGE OF PRIMARY MOSFET 50V/DIV 50ms/DIV Figure 5. Output Short-Circuit Waveforms at 72VIN Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 1 C1 Cap., Alum. Elect. 47µF, 80V, ±20% United Chemi-Con EMZA800ADA470MJA0G 2 2 C2, C3 Cap., X7S 4.7µF, 100V, 10%, 1210 TDK C3225X7S2A475K 3 2 C5, C6 Cap., X5R 47µF, 16V, 20%, 1210 Murata GRM32ER61C476ME15L 4 2 C7, C8 Cap., POSCAP 150µF, 16V, 10%, 7343 SANYO 16TQC150MYF 5 1 C9 Cap., X7S 1µF, 100V, 10%, 0805 TDK C2012X7S2A105K 6 1 C10 Cap., COG 5.6nF, 25V, 5%, 0603 TDK C1608C0G1E562J080AA 7 1 C11 Cap., X5R 4.7µF, 25V, 10%, 0805 AVX 08053D475KAT2A 8 1 C12 CAP CER 180pF, 450V, 5%, NP0 0805 TDK C2012C0G2W181J 9 2 C13, C24 Cap., X5R 1µF, 25V, 20%, 0603 AVX 06033D105MAT2A 10 1 C16 Cap., X7R 4700pF, 250V, 20%, 1812 MurataErie GA343DR7GD472KW01L 11 1 C18 Cap., X7R 3.3nF, 50V, 10%, 0603 AVX 06035C332KAT2A (to FT223A) 12 1 C21 Cap., X7R 1.2nF, 25V, 10%, 0603 AVX 06033C122KAT1A 13 1 C22 Cap., X5R 10µF, 16V, 20%, 0805 AVX 0805YD106MAT2A (from FT182/189A) 14 1 C26 Cap., NPO 100pF, 25V, 5%, 0603 AVX 06033A101JAT2A 15 1 C27 Cap., U2J 2.2nF, 250V, 5%, 0805 Murata GRM21A7U2D222JW31 16 2 D2, D3 Schottky Diode, 30A/80V, TO-263AB Vishay Semi. VBT3080S-E3 17 1 D4 Zener Diode, 11V SOD-123 Central Semi. CMHZ5241BTR 18 1 D5 Diode, 1A/200V SOD-123 Central Semi. CMMR1U-02TR 19 1 ISO1 Opto Iso., NEPOC Series NEC PS2801C-1-A 20 1 L1 Inductor, 22µH Würth Electronik 74435572200 21 1 L2 Inductor, 6.8µH Coilcraft XAL6060-682MEC 22 1 Q1 Mosfet-N Channel, 200V/36A SuperSO8 Infineon BSC320N20NS3G 23 1 R1 Res., Chip 86.6k, 0.06W, 1%, 0603 Vishay CRCW060386K6FKEA 24 1 R2 Res., Chip 1.74k, 0.10W, 1%, 0603 Vishay CRCW06031K74FKEA dc1963af 5 DEMO MANUAL DC1963A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER 25 26 1 R5 Res., Chip 1.43k, 0.10W, 1%, 0603 Vishay CRCW06031K43FKEA 1 R6 Res., Chip 118k, 0.06W, 1%, 0603 Vishay CRCW0603118KFKEA 27 1 R7 Res., Chip 40.2k, 0.06W, 1%, 0603 Vishay CRCW060340K2FKEA 28 2 R8, R9 Res/Jumper, Chip 0Ω, 1/16W, 1 AMP 0603 Vishay CRCW06030000Z0EA 29 1 R10 Res., RL Vert. 0.025, 1W, 1%, 0815 SSM Thin Film Tech. RL3720WT-R025-F 30 2 R13, R25 Res., Chip 10k, 0.06W, 5%, 0603 Vishay CRCW060310K0JNEA 31 1 R14 Res., Chip 3k, 0.06W, 5%, 0603 Vishay CRCW06033K00JNEA 32 1 R15 Res., Chip 3.3k, 0.06W, 5%, 0603 Vishay CRCW06033K30JNEA 33 2 R16, R23 Res., Chip 100k, 0.06W, 5%, 0603 Vishay CRCW0603100KJNEA 34 1 R17 Res., Chip 95.3k, 0.06W, 1%, 0603 Vishay CRCW060395K3FKEA 35 1 R20 Res., Chip 24.9k, 0.06W, 1%, 0603 Vishay CRCW060324K9FKEA 36 1 R21 Res., Chip 200, 0.125W, 1%, 0805 Vishay CRCW0805200RFKEA 37 1 R22 Res., Chip 499, 0.06W, 1%, 0603 Vishay CRCW0603499RFKEA 38 1 R24 Res., Chip 61.9k, 0.06W, 1%, 0603 Vishay CRCW060361K9FKEA 39 1 R26 Res., Chip 20.0k, 0.06W, 1%, 0603 Vishay CRCW060320K0FKEA 40 1 R27 Res., Chip 59.0k, 0.25W, 1%, 1206 Vishay CRCW120659K0FKEA 41 1 T1 XFMR., PULSE-PA4078NL PULSE PA4078NL 42 1 U1 I.C., Converter Controller TSSOP20-FE20 Linear Tech. Corp. LT8310EFE#PBF 43 1 U2 I.C., Prog. Reference SO8NB Linear Tech. Corp. LT1431CS8#PBF Optional Circuit Components 1 1 C14 Cap., 0603 5 E1, E2, E3, E4, E5 Turret, Testpoint Hardware 1 6 Mill Max 2501-2-00-80-00-00-07-0 dc1963af DEMO MANUAL DC1963A Schematic Diagram dc1963af 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. 7 DEMO MANUAL DC1963A 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 8 dc1963af Linear Technology Corporation LT 0714 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2014