DEMO MANUAL DC1764A LTC3122EDE High Efficiency 15V 2.5A Synchronous Step-Up Converter DESCRIPTION Demonstration circuit 1764A is a 5.5V input, 12V output at 800mA DC/DC power supply featuring the LTC®3122. The IC includes internal high and low side 2.5A 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 LTC3122 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 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 VIN = 5V, VOUT Load = 800mA 12V ±3% Output Current VIN = 5V, VOUT = 12V 800mA Output Voltage Ripple (PWM Mode) VIN = 5V, VOUT = 12V, VOUT Load = 500mA 40mVP-P Output Voltage Ripple (Burst Mode Operation) VIN = 5V, VOUT = 12V, VOUT Load = 50mA Output Voltage Switching Frequency 200mVP-P 1MHz ±15% dc1764af 1 DEMO MANUAL DC1764A QUICK START PROCEDURE This Demonstration circuit 1764A 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 V + 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. - A V A Load + Figure 1. Proper Measurement Equipment Setup dc1764af 2 DEMO MANUAL DC1764A QUICK START PROCEDURE 100 90 Burst Mode OPERATION 90 80 70 EFFICIENCY (%) EFFICIENCY (%) 80 100 60 50 40 PWM MODE 60 50 30 20 20 10 10 1 10 100 LOAD CURRENT (mA) 1000 PWM MODE 40 30 0 0.1 Burst Mode OPERATION 70 0 0.1 1 dc1764a F02 Figure 2. Efficiency VIN = 2V 10 100 LOAD CURRENT (mA) 1000 dc1764a F03 Figure 3. Efficiency VIN = 5V Figure 4. Measuring Output Voltage Ripple dc1764af 3 DEMO MANUAL DC1764A PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 1 C1 CAP CER, 10μF 10V 10% X5R 1206 TDK, C3216X5R1A106K 2 1 C2 CAP CER, 10μF 50V X7R 10% 0603 TDK, CGA3E2X7R1H104K 3 1 C3 CAP CER, 4.7μF 25V X5R 0805 TDK, C2012X5R1E475K 4 1 C5 CAP CER, 22μF 25V X5R 1210 MURATA, GRM32ER61E226KE15L 5 1 C7 CAP CER, 1μF 25V 10% X7R 0603 TDK, CGA3E1X7R1E105K 6 1 C8 CAP CER, 330pF 50V X7R 10% 0402 TDK, C1005X7R1H331K 7 1 L1 INDUCTOR, 4.7μH COILCRAFT, XAL4030-472MEB 8 1 R1 RES, 1.00M 1/16W 1% SMD 0402 PANASONIC, ERJ-2RKF1004X 9 1 R2 RES, 57.6k 1/10W 1% 0402 SMD PANASONIC, ERJ-2RKF5762X 10 1 R4 RES, 1.02M 1/16W 1% 0402 SMD VISHAY, CRCW04021M02FKTD 11 1 R5 RES, 113k 1/10W 1% 0402 SMD PANASONIC, ERJ-2RKF1133X 12 1 R6 RES, 86.6k 1/10W 1% 0402 SMD VISHAY, CRCW040286K6FKED 13 1 U1 15V, 2.5A SYNCHRONOUS BOOST DC/DC CONVERTER LINEAR TECH;, LTC3122EDE Additional Demo Board Circuit Components 1 0 C4, C9 CAP CER, 0402 OPT 2 0 C6 CAP CER, 1210 OPT 3 0 R3 RES, 0402 OPT Hardware: For Demo Board Only 1 6 E1-E6 TURRET, 0.09 DIA MILL-MAX, 2501-2-00-80-00-00-07-0 2 2 JP1, JP2 JMP, 3 PIN 1 ROW 0.079CC SAMTEC, TMM-103-02-L-S 3 2 XJP1, XJP2 SHUNT, 0.079" CENTER SAMTEC, 2SN-BK-G 4 4 STAND OFF STAND-OFF, NYLON 0.50" Tall KEYSTONE, 8832 (SNAP ON) dc1764af 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 D 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 MODE 1 PWM 2 3 BURST JP2 E4 JP1 RUN E3 E2 SYNC ON OFF RUN GND E1 VIN 1.8V - 5.5V 4 4 R2 57.6k 1% L1 2 PGND 10 GND C3 4.7uF 0805 VCC VCC 5 VC 7 FB 8 SW 1 CAP 12 VOUT 11 R6 86.6k 1% C8 330pF 0402 C2 0.1uF 50V CUSTOMER NOTICE 3 3 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. 4 PWM/SYNC 6 RT 3 VIN 9 SHDN/ U1 LTC3122EDE XAL4030 4.7uH GND 13 5 FRAN H. 2 SCALE = NONE NC PCB DES. APP ENG. APPROVALS C9 OPT 0402 1% R3 OPT C4 OPT 0402 2 2 REV DESCRIPTION TECHNOLOGY C5 22uF 25V 1210 C7 1uF 25V E6 E5 GND VOUT 12V 500mA FRAN H. APPROVED DATE 05-16-12 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only C6 OPT 1210 VOUT PRODUCTION FAB DATE: N/A SIZE LTC3122EDE DEMO CIRCUIT 1764A 05 - 16 - 12 IC NO. 1 SHEET 1 OF 1 2 REV. 15V, 2.5A SYNCHRONOUS BOOST DC / DC CONVERTER TITLE: SCHEMATIC R5 113K 1% R4 1.02M 1% __ ECO 1 REVISION HISTORY A B C D DEMO MANUAL DC1764A SCHEMATIC DIAGRAM dc1764af 5 DEMO MANUAL DC1764A 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 dc1764af 6 Linear Technology Corporation LT 0812 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2012