DEMO MANUAL DC1687A LTC3115EDHD-1 40V, 2A Synchronous Buck-Boost DC/DC Converter Description Demonstration circuit 1687A features the LTC®3115-1, a high voltage monolithic synchronous buck-boost converter. The DC1687A demo board has two user selectable operating modes: Burst Mode® operation and forced continuous operation (fixed frequency PWM) (JP1). There is also an accurate programmable RUN pin which is used to enable the converter (JP2). The DC1687A operates with a 2.7V to 40V input voltage range. The demo board has been designed with the output voltage set to 5.0V. The LTC3115-1 incorporates a proprietary low noise switching algorithm which optimizes efficiency with input voltages above, below or equal to the output voltage and ensures seamless transitions between operating modes. The demo board has been programmed to operate at 1MHz in PWM mode to optimize small size with high efficiency operation. The demo board also has optional provisions to back feed VCC in order to increase efficiency in some 5V output applications. There is also a provision for an optional Schottky diode from SW2 to VOUT for applications where VOUT is greater than 20V and short circuit protection is desired. Consult the data sheet for more information on these options. Figures 1 and 2 show typical demo board efficiency. The LTC3115-1 data sheet has detailed information about the operation, specifications, and applications of the part. The data sheet should be read in conjunction with this quick start guide. Design files for this circuit board are available at http://www.linear.com/demo L, LT, LTC, LTM, µModule, Burst Mode, 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 VALUE Input Voltage Range 2.7V to 40V VOUT 5.0V IOUT (See Note 1) 1A For VIN ≥ 3.6V, 2A For VIN > 6V Efficiency See Figures 1 and 2 Note 1: The Demo Board output current is a function of VIN. Please refer to the data sheet for more information dc1687af 1 DEMO MANUAL DC1687A Quick Start Procedure Using short twisted pair leads for any power connections and with all loads and power supplies off, refer to Figure 3 for the proper measurement and equipment setup. The battery/power supply (PS1) should not be connected to the circuit until told to do so in the procedure below. 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), or by using an oscilloscope probe tip jack. 1.Jumper and PS1 settings to start: PS1 = OFF JP1 (PWM) = fixed frequency JP2 (RUN) = ON 4.Turn on PS1 and slowly increase voltage until the voltage at VIN is 4.0V. 5.Verify VOUT is ~5.0V. 6.VIN can now be varied between 2.7V and 40.0V. IOUT may need to be reduced for VIN < 4V. VOUT should remain in regulation. 7.Load current (IOUT) can also be varied. The maximum IOUT is a function of VIN and the current limit. Consult the data sheet for more information on IOUT vs VIN. In general for VIN > 3.6V IOUT can be increased to 1A. For VIN > 6V IOUT can be increased to 2A. 8.For operation in Burst Mode operation move Jumper JP1 to burst. IOUT is limited in Burst Mode operation. See the data sheet for more information. 9. NOTE: If VOUT drops out of regulation, check to be sure the maximum load has not been exceeded, or that VIN is not below the minimum value for regulation (see data sheet) 100 100 90 90 EFFICIENCY (%) EFFICIENCY (%) 2.With power OFF connect the power supply (PS1) as shown in Figure 3. If accurate current measurements are desired (for efficiency calculation for example) then connect an ammeter in series with the supply as shown. The ammeter is not required however. 3.Connect a 500mA load to VOUT as shown in Figure 3 (10Ω for VOUT = 5V). Connect an ammeter if accurate current measurement or monitoring is desired. 80 70 60 50 80 70 60 LOAD = 500mA LOAD = 1A 0 5 10 15 20 25 30 35 VIN (V) Figure 1. DC1687A Efficiency in PWM Mode 40 50 LOAD = 100mA LOAD = 200mA LOAD = 300mA 0 5 10 15 20 25 30 35 40 VIN (V) Figure 2. DC1687A Efficiency in Burst Mode Operation dc1687af 2 DEMO MANUAL DC1687A quick start procedure Figure 3. Proper Measurement Equipment Setup GND VIN Figure 4. Measuring Input or Output Ripple dc1687af 3 DEMO MANUAL DC1687A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 2 C1, C2 CAP, CER, 0.10µF, 16V, X7R, ±20%, 0402 TDK, C1005X7R1C104M 2 1 C4 CAP, CER, 33pF, 50V, C0G, 5%, 0402 TDK, C1005C0G1H330J 3 1 C6 CAP, CER, 47µF, 10V, 20%, X5R, 1812 TDK, C4532X5R1A476M 4 1 C7 CAP, CER, 1.0µF, 25V, X5R, 0603 TDK, C1608X5R1E105M 5 1 C8 CAP, CER, 3300pF, 50V, 5%, NP0, 0603 TDK, C1608C0G1H332J 6 1 C9 CAP, CER, 4.7µF, 6.3V, X5R, 20%, 0603 TDK, C1608X5R0J475M 7 1 C10 CAP, CER, 4.7µF, 50V, 20%, X7R, 1812 TDK, C4532X7R1H475M/2.00 8 1 C11 CAP, CER, 10pF, 50V, C0G, 0402 TDK, C1005C0G1H100D 9 1 C12 CAP, CER, 1.0µF, 50V, X7R, 20%, 1206 TDK, C3216X7R1H105M 10 1 C13 CAP, CER, 0.1µF, 50V, 20%, X7R, 0805 TDK, C2012X7R1H104M/0.85 11 1 L1 INDUCTOR, 10µH, ±20% COILCRAFT, MSS1048-103MLB 12 2 R1, R6 RES, 1.00MΩ, 1/16W, 1%, 0402, SMD VISHAY, CRCW04021M00FKED 13 1 R2 RES, 249kΩ, 1/16W, 1%, 0402, SMD VISHAY, CRCW0402249KFKED 14 1 R3 RES, 15.0kΩ, 1/10W, 1%, 0402, SMD PANASONIC, ERJ-2RKF1502X 15 1 R4 RES, 60.4kΩ, 1/10W, 1%, 0402, SMD PANASONIC, ERJ-2RKF6042X 16 1 R7 RES, 47.5kΩ, 1/16W, 1%, 0402, SMD VISHAY, CRCW040247K5FKED 17 1 U1 40V, 2A Buck Boost DC/DC Converter LINEAR TECHNOLOGY, LTC3115EDHD-1 Additional Demo Board Circuit Components 1 0 C3 CAP, CER, 1000PF, 50V, 20%, X7R, 0402 (OPT) TDK, C1005X7R1H102M 2 0 C5 CAP, ALUM, 150µF, 50V, 20%, RADIAL (OPT) PANASONIC, EEU-FM1H151 3 0 D1 DIODE SCHOTTKY, 20V, 1A, SOD323 (OPT) NXP SEMI, PMEG2010EA 4 0 D2 DIODE SCHOTTKY, 60V, 3A, SMA (OPT) DIODES INC.,B360A-13 5 0 R5 RES, 0402 (OPT) Hardware For Demo Board Only: 1 4 E1–E4 TP, TURRET, 0.094", PBF MILL-MAX, 2501-2-00-80-00-00-07-0 2 2 JP1, JP2 JMP, 3-PIN 1 ROW .079CC SAMTEC, TMM-103-02-L-S 3 2 XJP1, XJP2 4 4 SHUNT, .079" CENTER SAMTEC, 2SN-BK-G SPACER STACKING #4 SCREW NYLON .500" KEYSTONE, 8833 dc1687af 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. 1 2 3 4 E3 JP2 RUN C5 1 2 RUN 3 VIN + A JP1 1 2 3 VCC PWM OPT OPT PWM C3 C12 1uF 50V 1206 R5 R6 1M OPT FIXED FREQ SYNCH BURST MODE OFF ON GND E4 C10 4.7uF 50V 1812 2.7V - 40V VIN C9 4.7uF 6.3V 0603 R7 47.5k PWM VCC 4 8 5 16 9 11 14 10 13 GND RT GND 1 6 7 3 12 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. OPT C SCALE = NONE J.NOON NC C11 10pF 0603 DATE: N/A SIZE R3 15k C4 33pF D DESCRIPTION R2 249k R1 1M C7 1uF 25V 0603 E2 GND VOUT 5.0V / 2A 02-08-12 D LTC3115EDHD-1 DEMO CIRCUIT 1687A E SHEET 1 40V, 2A BUCK BOOST DC / DC CONVERTER IC NO. DATE 02-08-12 UNLESS NOTED: RESISTORS: OHMS, 0402, 1% CAPACITORS: uF, 0402 C6 47uF 10V 1812 E1 J.NOON APPROVED E OF 1 2 REV. 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only PRODUCTION FAB REVISION HISTORY TECHNOLOGY 2 - C8 3300pF REV ECO TITLE: SCHEMATIC R4 60.4k C2 0.1uF VOUT RUN D2 B360A APPROVALS 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. APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. B C U1 LTC3115EDHD-1 RUN VC FB PVOUT BST2 PWM/SYNC VCC L1 10uH PVCC PVIN VIN BST1 CUSTOMER NOTICE C13 0.1uF 0805 OPT D1 PMEG2010EA VOUT VIN C1 0.1uF 15 SW1 2 SW2 B PGND 17 A 1 2 3 4 DEMO MANUAL DC1687A Schematic Diagram dc1687af 5 DEMO MANUAL DC1687A 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 dc1687af 6 Linear Technology Corporation LT 0412 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2012