DEMO MANUAL DC1980A LT3514 Triple Step-Down Switching Regulator with 100% Duty Cycle Operation Description 100 Each converter is synchronized to either a common external clock input or a resistor programmable 250kHz to 2.2MHz internal oscillator. Programmable frequency allows optimization between efficiency and external component size. Each output can be independently disabled using its own RUN/SS pin. 95 90 EFFICIENCY (%) Demonstration circuit 1980A is a triple current mode PWM step-down DC/DC converter featuring the LT®3514. The demo circuit is designed for 5V, 3.3V and 1.8V outputs from a 5.4V to 36V input. The current capability of 5V and 1.8V outputs is 1A and the 3.3V output is capable of 2A output. Individual soft-start and current limit for each output as well as frequency synchronous function simplify the complex design of triple-output power converters. 85 80 75 70 65 60 5 10 15 20 25 VIN (V) 35 30 40 DC1980a F01 Figure 1. System Efficiency at f = 1MHz with IOUT1 = IOUT4 = 1A and IOUT3 = 2A The LT3514 data sheet gives complete description of the device, operation and application information. The data sheet must be read in conjunction with this quick start guide for the demo circuit 1980A. 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. DC1980a F02 Figure 2. Thermal Image at VIN = 12V, f = 1MHz with IOUT1 = IOUT4 = 1A and IOUT3 = 2A Performance Summary Specifications are at TA = 25°C SYMBOL PARAMETER CONDITIONS VIN Input Supply Range 5.4 VOUT1 Output Voltage 1 4.85 5 VOUT3 Output Voltage 3 3.2 VOUT4 Output Voltage 4 1.746 Frequency Switching Frequency VIN = 12V 0.9 IOUT1 VOUT1 Maximum Output Current VIN = 5.4V ~ 36V MIN 1 TYP MAX UNITS 36 V 5.15 V 3.3 3.4 V 1.8 1.854 V 1 1.1 MHz A dc1980af 1 DEMO MANUAL DC1980A Performance Summary Specifications are at TA = 25°C SYMBOL PARAMETER CONDITIONS IOUT3 VOUT3 Maximum Output Current VIN = 5.4V ~ 36V MIN 2 IOUT4 VOUT4 Maximum Output Current VIN = 5.4V ~ 36V 1 TYP MAX UNITS A A VOUT1(AC) VOUT1 Output Ripple VIN = 5.4V ~ 36V, IOUT1 = 1A 25 mV VOUT3(AC) VOUT3 Output Ripple VIN = 5.4V ~ 36V, IOUT3 = 2A 25 mV VOUT4(AC) VOUT4 Output Ripple VIN = 5.4V ~ 36V, IOUT4 = 1A 25 mV Quick Start Procedure Demonstration circuit 1980A is easy to set up to evaluate the performance of the LT3514. Refer to Figure 3 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. Measure the input or output voltage ripple by touching the probe tip directly across the VIN or VOUT and GND terminals. See Figure 4 for proper scope probe technique. 1.Place JP1 to JP4 on ON position. 3.Turn on the power at the input. NOTE. Make sure that the input voltage does not exceed 36V 4.Check for the proper output voltages. NOTE. If there is no output, temporarily disconnect the load to make sure that the load is not set too high. 5.Once the proper output voltages are established, adjust the load within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters. 2.With power off, connect the input power supply to VIN and GND. dc1980af 2 DEMO MANUAL DC1980A Quick Start Procedure DC1980a F03 Figure 3. DC1980A Proper Equipment Setup VIN OR VOUT GND DC1980A F04 Figure 4. Measuring Input or Output Ripple dc1980af 3 DEMO MANUAL DC1980A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 1 C1 CAP, X5R, 22µF, 6.3V, 10% 0805 TDK, C2012X5R0J226K 2 1 C3 CAP, X5R, 47µF, 6.3V, 10% 1206 MURATA, GRM31CR60J476KE19L 3 1 C4 CAP, X5R, 22µF, 10V, 10% 0805 TDK, C2012X5R1A226K 4 1 C5 CAP, X5R, 2.2µF, 6.3V, 10% 0603 TDK, C1608X5R0J225K 5 4 C6, C19, C26, C27 CAP, X5R, 1µF, 50V, 10% 0603 TDK, C1608X5R1H105K 6 3 C7, C17, C18 CAP, X7R, 47nF, 10V, 10% 0603 AVX, 0603ZC473KAT2A 7 1 C21 CAP, NP0, 330pF, 50V, 5% 0603 AVX 06035A331JAT2A 8 1 C23 CAP, NP0, 100pF, 50V, 5% 0603 AVX 06035A101JAT 9 2 D1, D4 DIODE, SCHOTTKY BARRIER RECTIFIER ON SEMI, MBRM140T3G 10 1 D3 SCHOTTKY RECTIFIER, SMA VISHAY, B240A-M3 11 1 L1 IND, 8.2µH SUMIDA, CDRH5D28NP-8R2NC 12 1 L3 IND, 4.7µH NIC, NPIM73P4R7MTRF 13 1 L4 IND, 4.2µH SUMIDA, CDRH5D28NP-4R2NC 14 1 L5 IND, 10µH COILCRAFT, XPL2010-103MLB 15 1 R1 RES, CHIP, 12.7k, 1% 1/16W, 0603 VISHAY, CRCW060312K7FKED 16 1 R3 RES, CHIP, 31.6k, 1% 1/16W, 0603 VISHAY, CRCW060331K6FKED 17 1 R4 RES, CHIP, 53.6k, 1%, 1/16W, 0603 VISHAY, CRCW060353K6FKED 18 1 R5 RES, CHIP, 18.2k, 1% 1/16W, 0603 VISHAY, CRCW060318K2FKED 19 1 R6 RES, CHIP, 200k, 5% 1/16W, 0603 VISHAY, CRCW0603200KJNED 20 1 R7 RES, CHIP, 475k, 1% 1/16W, 0603 VISHAY, CRCW0603475KFKED 21 1 R8 RES, CHIP, 100k, 1% 1/16W, 0603 VISHAY, CRCW0603100KFKED 22 3 R9, R11, R12 RES, CHIP, 10k, 1% 1/16W, 0603 VISHAY, CRCW060310K0FKED 23 1 U1 IC, 36V TRIPLE BUCK REGULATOR LINEAR TECHNOLOGY, LT3514EUFD#PBF Additional Demo Board Circuit Components 1 1 C8 CAP, ALUM, 22µF, 50V, 20% SUN ELECT, 50CE22BS 2 0 C10 (OPT) CAP, X7R, 0.01µF, 50V,10% 0603 TDK, C1608X7R1H103K OPTION 3 0 C11 (OPT) CAP, X7R, 2.2µF, 50V, 10% 1206 MURATA, GCM31CR71H225KA55L 4 3 C12 TO C14 CAP, X7R, 0.1µF, 50V, 10% 0603 MURATA, GRM188R71H104KA93D 5 0 C20, C25, C28 (OPT) CAP, X7R, 0.1µF, 50V, 10% 0603 MURATA, GRM188R71H104KA93D 6 0 C24 (OPT) CAP, 0603 7 0 FB1 (OPT) FERRITE BEAD, OPTION OPTION 8 0 L6 (OPT) IND, 8.2µH OPTION VISHAY, IHLP-2525CZ-01 OPTION Hardware: For Demo Board Only 1 15 E1 TO E15 TURRET MILL MAX, 2501-2-00-80-00-00-07-0 2 4 JP1 TO JP4 HEADER, 3PIN, 2mm SAMTEC, TMM-103-02-L-S 3 4 xJP1 TO xJP4 SHUNT, 2mm SAMTEC, 2SN-BK-G dc1980af 4 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 SYNC RUN/SS4 RUN/SS3 RUN/SS1 PG GND R8 100k 1% C18 47nF 10V C17 47nF 10V C19 1uF 50V VOUT4 C6 1uF 50V C7 47nF 10V + ON OFF ON OFF C27 1uF 50V RUN/SS4 ON OFF C20 OPT 50V C25 OPT 50V C28 OPT 50V 5 1. ALL RESISTORS ARE 0603. ALL CAPACITORS ARE 0603. L5 10uH OFF JP1 1 2 R5 18.2k 1% (1MHz) R6 200K VIN EN/UVLO R7 3 475K 1% ON SYNC RUN/SS4 RUN/SS3 RUN/SS3 RUN/SS1 RUN/SS1 PG C26 1uF 50V C5 2.2uF 6.3V 4 4 NOTE: UNLESS OTHERWISE SPECIFIED E13 E14 E15 E12 E11 E2 VIN E1 C8 5.4V - 36V 22uF 50V 1 JP2 1 JP4 1 JP3 VIN C11 2.2uF 50V 1206 OPTIONAL CIRCUIT C10 0.01uF 50V FB1 L6 FERRITE BEAD 8.2uH 2 2 2 D VEMI 3 3 3 17 12 15 13 23 16 28 26 11 9 24 25 RT/SYNC RUN/SS4 RUN/SS3 RUN/SS1 PG EN/UVLO VIN VIN VIN VIN SW5 SKY LT3514EUFD U1 NC 1 NC 2 NC 14 NC 22 3 3 GND 29 GND 10 FB4 DA4 SW4 FB3 DA3 SW3 FB1 DA1 SW1 GND 18 GND 27 5 19 8 7 21 3 4 20 6 5 L4 4.2uH CDRH5D28-4R2 D3 B240A MBRM140T3G D1 R4 53.6k 1% 2 R1 12.7k 1% R3 31.6k 1% L3 4.7uH NPIM73P4R7MTRF D4 MBRM140T3G L1 8.2uH CDRH5D28-8R2 2 1% 10k 1% R9 1% R11 C21 330pF 10k C23 100pF VOUT3 10k R12 C24 OPT C1 22uF 6.3V 0805 VOUT4 C12 0.1uF 50V C14 C3 47uF 0.1uF 50V 6.3V 1206 C4 C13 22uF 0.1uF 10V 50V 0805 1 1 E4 E3 E8 E7 E10 E9 GND 1.8V / 1A VOUT4 GND 3.3V / 2A VOUT3 GND VOUT1 5V / 1A A B C D DEMO MANUAL DC1980A Schematic Diagram dc1980af 5 DEMO MANUAL DC1980A 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 dc1980af 6 Linear Technology Corporation LT 0713 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2013