DEMO MANUAL DC2372A LTC3121EDE High Efficiency 15V 1.5A Synchronous Step-Up Converter Description Demonstration circuit 2372A is a 5.5V input, 12V output at 400mA DC/DC power supply featuring the LTC®3121. The IC includes internal high and low side 1.5A switches and features selectable PWM or Burst Mode® operation for high efficiency at low output current. The board operates from an input voltage as low as 1.8V and continues to operate down to 500mV once started. The output is fixed at 12V although other voltages between 2.2V and 15V can be selected by resistor changes. The IC includes soft-start and input current limit, adjustable switching frequency with the ability to synchronize to an external clock, and output overvoltage protection with output disconnect. Performance Summary PARAMETER Included on the board are jumpers for ON/OFF and operating MODE, PWM or BURST. Terminals are included for connecting VIN and VOUT as well as ON/OFF and SYNC. The LTC3121 data sheet gives a complete description of the IC operation and application information. The data sheet must be read in conjunction with this quick start guide. Design files for this circuit board are available at http://www.linear.com/demo/DC2372A L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode 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 VALUE 1.8V to 5.5V Output Voltage VIN = 5V, VOUT Load = 400mA 12V ±3% Output Current VIN = 5V, VOUT = 12V 400mA Output Voltage Ripple (PWM Mode) VIN = 5V, VOUT = 12V, VOUT Load = 400mA 40mVP-P Output Voltage Ripple (Burst Mode Operation) VIN = 5V, VOUT = 12V, VOUT Load = 50mA Switching Frequency 200mVP-P 1MHz ±15% dc2372af 1 DEMO MANUAL DC2372A Quick Start Procedure This Demonstration circuit 2372A can be evaluated using the setup shown in Figure 1. 1.Connect voltmeters to VIN and VOUT, select upper positions for jumper JP1 (ON) and JP2 (PWM). 2.With input power supply set for 0V, connect the supply to VIN and GND terminals. 3.Slowly increase the input power supply to 1.8V. Observe output voltage and verify that it meets the specifications in the Performance Summary table. 6V, 3A Adjustable Power Supply 4.Connect a suitable load resistor or active load to the output terminals and verify that it meets specifications in the Performance Summary table. 5.Use a scope to monitor the output voltage ripple in both PWM mode and Burst Mode operation by moving the mode jumper JP2 to the appropriate position. See Figure 4 for correct method for evaluating output ripple. 6.Note: If jumper JP2 is set for Burst Mode operation, maximum output current is limited to approximately 100mA at 5VIN. – – LOAD + + Figure 1. Proper Measurement Equipment Setup 2 dc2372af DEMO MANUAL DC2372A Quick Start Procedure 100 90 Burst Mode OPERATION 90 80 70 EFFICIENCY (%) EFFICIENCY (%) 80 100 60 50 40 PWM MODE 30 60 50 30 20 10 10 1 10 100 LOAD CURRENT (mA) 1000 PWM MODE 40 20 0 0.1 Burst Mode OPERATION 70 0 0.1 1 dc2372a F02 Figure 2. Efficiency VIN = 2V 10 100 LOAD CURRENT (mA) 1000 dc2372a F03 Figure 3. Efficiency VIN = 5V Figure 4. Measuring Output Voltage Ripple dc2372af 3 DEMO MANUAL DC2372A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER 1 1 C1 CAP 10μF X5R 10V 10%1206 TDK, C3216X5R1A106K 2 1 C2 CAP 0.10μF X7R 50V 10% 0603 TDK, CGA3E2X7R1H104K080AA 3 1 C3 CAP 4.7μF X5R 25V 10% 0805 TDK,C2012X5R1E475K085AC 4 0 C4 CAP 0402 OPT OPT 5 1 C5 CAP 22μF 25V X5R 10% 1210 MURATA, GRM32ER61E226KE15L 6 1 C7 CAP 1μF X7R 25V 10% 0603 TDK, CGA3E1X7R1E105K080AC 7 1 C8 CAP 1nF 50V X7R 10% 0402 AVX, 04025C102KAT2A 8 1 C9 CAP 10pF C0G 25V 5% 0402 AVX, 04023A100JAT2A 9 6 E1-E6 TEST POINT, TURRET, 0.094 MTG. HOLE MILL-MAX, 2501-2-00-80-00-00-07-0 10 2 JP2, JP1 CONN, HEADER, 1 × 3, 2mm SAMTEC, TMM-103-02-L-S 11 2 XJP1, XJP2 SHUNT, 2mm SAMTEC, 2SN-BK-G 12 1 L1 IND, PWR 6.8μH, 20%, XAL40xx Series COILCRAFT, XAL4030-682ME 13 1 R1 RES, 1MΩ 1/10W 1% 0402 PANASONIC, ERJ2RKF1004X 14 1 R2 RES, 57.6kΩ 1/10W 1% 0402 PANASONIC, ERJ2RKF5762X 15 0 R3 RES,0402 OPT OPT 16 1 R4 RES 1.02MΩ 1/10W 1% 0402 VISHAY, CRCW04021M02FKED 17 1 R5 RES, 113kΩ 1/10W 1% 0402 PANASONIC, ERJ2RKF1133X 18 1 R6 RES, 82.5kΩ 1/10W 1% 0402 PANASONIC, ERJ2RKF8252X 19 1 U1 IC, LTC3121EDE LINEAR TECH, LTC3121EDE STAND OFF 20 4 STAND-OFF, NYLON 0.500" KEYSTONE, 8832 (SNAP ON) 21 1 FAB, PRINTED CIRCUIT BOARD LINEAR TECH, DEMO CIRCUIT 2372A 22 2 STENCILS, TOP & BOTTOM LINEAR TECH, DEMO CIRCUIT 2372A 4 dc2372af 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 D JP2 1 2 3 1 2 3 VCC C1 10uF 10V 1206 VIN R1 1M 1% 5 2. INSTALL SHUNTS AS SHOWN. 1. ALL RESISTORS ARE 0402 AND CAPACITORS ARE 0603. NOTE: UNLESS OTHERWISE SPECIFIED BURST PWM MODE E4 JP1 RUN E3 E2 SYNC ON OFF RUN GND E1 VIN 1.8V - 5.5V 4 4 R2 57.6k 1% 2 10 6 4 9 3 PGND GND RT SW VCC VC FB VOUT CAP 1 C3 4.7uF 0805 5 VCC 7 8 11 12 R6 82.5k 1% C8 1nF 0402 C2 0.1uF 50V 3 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. CUSTOMER NOTICE 3 1% R3 OPT C4 OPT 0402 2 2 SCALE = NONE Goran P. HZ APPROVALS C9 10pF 0402 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. PWM/SYNC SHDN/ VIN XAL4030 U1 LTC3121EDE 6.8uH L1 GND 13 5 1 C5 22uF 25V 1210 E6 GND 12V 400mA VOUT DATE 12-5-14 A B C D DATE: N/A SIZE LTC3121EDE DEMO CIRCUIT 2372A 05 - 16 - 12 IC NO. 1 SHEET 1 OF 1 1 REV. 15V, 1.5A SYNCHRONOUS BOOST DC / DC CONVERTER 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only C7 1uF 25V E5 Goran P. PROTOTYPE VOUT APPROVED DESCRIPTION TECHNOLOGY REV TITLE: SCHEMATIC R5 113K 1% R4 1.02M 1% __ ECO 1 REVISION HISTORY DEMO MANUAL DC2372A Schematic Diagram dc2372af 5 DEMO MANUAL DC2372A 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 dc2372af Linear Technology Corporation LT 0715 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 2015