DEMO MANUAL DC2169A LT8616 Dual 42V Synchronous Monolithic Step-Down Regulator with 6.5µA Quiescent Current Description Demonstration circuit 2169A is a dual monolithic step-down DC/DC switching regulator featuring the LT®8616. The LT8616 is a high efficiency, high speed, dual synchronous monolithic step-down switching regulator that consumes only 6.5μA of quiescent current with both channels enabled. The demo circuit is designed for 5V, 1.5A and 3.3V, 2.5A outputs. Both channels contain all switches and necessary circuitry to minimize the external components and solution size. Fast minimum ON time of 35ns enables high VIN to low VOUT conversion at high switching frequency. Independent input voltage, feedback, soft-start and power good pins for each channel simplify complex power supply tracking/sequencing requirements. The inputs of the two channels are connected on the demo board by default. They can also be separated by removing the 0Ω resistor (R13) from the board. Each output can be independently disabled using its own EN/UV pin, while VIN1 must be connected to 3.4V or above even if only channel 2 is in use. The demo board has an EMI filter installed between VIN2 and VEMI. To use the EMI filter, the inputs should be tied to VEMI. The switching frequency of both channels can be programmed either via an oscillator resistor or a common external clock up to 3MHz.The SYNC pin on the demo board is grounded by default for Burst Mode® operation. Performance Summary To synchronize to an external clock, move JP1 to SYNC/ MODE and apply the external clock to the SYNC/MODE turret. The RT resistor (R5) should be chosen to set the LT8616 internal switching frequency at least 20% below the lowest synchronization input. Low ripple Burst Mode operation increases the efficiency at the light load while keeping the output ripple low. Figure 1 and Figure 2 show the demo board efficiency for each channel at 12V input voltage in Burst Mode operation. Figure 3 shows the temperature rising on DC2169A demo board with different input voltages under full load conditions on both channels. The LT8616 data sheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with this demo manual for DC2169A. The LT8616 is assembled in a 28-lead plastic TSSOP package. Proper board layout is essential for both low EMI operation and maximum thermal performance. See the data sheet sections for details. Design files for this circuit board are available at http://www.linear.com/demo/DC2169A 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 SYMBOL PARAMETER CONDITIONS MIN VIN1 Channel 1 Input Supply Range VIN2 Channel 2 Input Supply Range 4.1 VOUT1 Channel 1 Output Voltage 4.88 VOUT2 Channel 2 Output Voltage fSW Switching Frequency IOUT1 Channel 1 Max Output Current IOUT2 Channel 2 Max Output Current EFE Efficiency at DC TYP 5.8 RT = 14.7kΩ 5.02 UNITS 42 V 42 V 5.15 V 3.21 3.29 3.37 V 1.85 2.05 2.25 MHz 1.5 A 2.5 VIN1 = VIN2 = 12V, IOUT1 = 1.5A, IOUT2 = 2.5A MAX A 85.1 % dc2169af 1 DEMO MANUAL DC2169A Performance Summary 100 EFFICIENCY (%) 90 80 70 60 50 fSW = 2MHz VIN1 = 12V VOUT1 = 5V 0 0.3 0.9 1.2 0.6 LOAD CURRENT (A) 1.5 DC2169A F01 Figure 1. LT8616 Channel 1 Efficiency vs Load Current 100 EFFICIENCY (%) 90 80 70 60 50 fSW = 2MHz VIN2 = 12V VOUT2 = 3.3V 0 0.5 1.5 1 LOAD CURRENT (A) 2 2.5 DC2169A F02 Figure 2. LT8616 Channel 2 Efficiency vs Load Current TEMPERATURE RISING (°C) 100 fSW = 2.05MHz VOUT1 = 5V, IOUT1 = 1.5A 80 60 40 20 8 16 24 32 INPUT VOLTAGE (V) 40 DC2169A F03 Figure 3. LT8616 Temperature Rising vs Input Voltage 2 dc2169af DEMO MANUAL DC2169A Quick Start Procedure DC2169A is easy to set up to evaluate the performance of the LT8616. Refer to Figure 4 for proper measurement equipment setup and follow the procedure below: 4.Turn on the power at the input. 5.Check for the proper output voltages (5V and 3.3V). NOTE: If there is no output, temporarily disconnect the load to make sure that the load is not set too high or is shorted. 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 5 for the proper scope technique. 6.Once the proper output voltages are established, adjust the load within the operating ranges and observe the output voltage regulation, ripple voltage, efficiency and other parameters. 1.Place JP1 on the Burst Mode position. 7.An external clock can be added to the SYNC terminal when SYNC function is used (JP1 on the SYNC/MODE position). Please make sure that the SYNC frequency is at least 20% higher than the set switching frequency. See the data sheet section Synchronization. 2.With power off, connect the input power supply to VEMI and GND. Make sure that the input voltage does not exceed 42V. 3.With power off, connect loads from VOUT1 to GND, and VOUT2 to GND. Figure 4. Proper Measurement Equipment Setup VOUT GND Figure 5. Measuring Input or Output Ripple dc2169af 3 DEMO MANUAL DC2169A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 2 C2, C3 CAP., X7R, 0.1µF, 10V, 10% 0402 SAMSUNG, CL05B104KP5NNNC 2 1 C4 CAP., X7R, 22µF, 10V, 10% 1210 MURATA, GRM32ER71A226KE20L 3 1 C5 CAP., X7R, 47µF, 10V, 10% 1210 MURATA, GRM32ER71A476KE15L 4 2 C6, C7 CAP., X7R, 0.01µF, 10V, 10% 0603 AVX, 0603ZC103KAT2A 5 2 C8, C9 CAP., C0G, 4.7pF, 50V, ±0.25pF 0603 AVX, 06035A4R7CAT2A 6 2 C10, C11 CAP., X7R, 2.2µF, 50V, 10% 1206 MURATA, GRM31CR71H225KA88L 7 5 C12, C17, C19, C27, C28 CAP., X7R, 1µF, 10V, 10% 0603 AVX, 0603ZC105KAT2A 8 4 C13, C14, C15, C16 CAP., X7R, 0.1µF, 50V, 10% 0402 TDK, C1005X7R1H104K050BB 9 1 L1 IND., 3.3µH, XAL4030 COILCRAFT, XAL4030-332ME 10 1 L2 IND., 2.2µH, XFL4020 COILCRAFT, XFL4020-222ME 11 6 R1, R3, R6, R8, R10, R11 RES., CHIP, 1M, 0.1W, 1%, 0603 VISHAY, CRCW06031M00FKEA 12 1 R2 RES., CHIP, 187k, 0.1W, 1%, 0603 VISHAY, CRCW0603187KFKEA 13 1 R4 RES., CHIP, 316k, 0.1W, 1%, 0603 VISHAY, CRCW0603316KFKEA 14 1 R5 RES., CHIP, 14.7k, 0.1W, 1%, 0603 VISHAY, CRCW060314K7FKEA 15 2 R7, R13 RES., CHIP, 0Ω, 0.1W, 0603 VISHAY, CRCW06030000Z0EA 16 1 U1 IC., LT8616EFE TSSOP-28/EB LINEAR TECH., LT8616EFE#PBF CAP., ALUM., 22µF, 63V, SUN ELECTRONIC INDUSTRIES CORP., 63CE22BS Additional Demo Board Circuit Components 1 2 C1, C18 2 1 L3 CHIP BEAD, 30Ω, MPZ2012 TDK, MPZ2012S300AT 3 1 L4 IND., 0.22µH, IHLP1212AB VISHAY, IHLP1212ABERR22M11 4 1 C23 CAP., X7R, 4.7µF, 50V, 10% 1206 SAMSUNG, CL31B475KBHNNNE 5 1 C24 CAP., X7R, 10µF, 50V, 10% 1210 MURATA, GRM32ER71H106KA12L 6 2 C25, C26 CAP., X7R, 0.1µF, 50V, 10% 0402 TDK, C1005X7R1H104K050BB 7 0 R9, R12 (OPT) RES., CHIP, 0603 Hardware: For Demo Board Only 1 16 E1-E16 TESTPOINT, TURRET, .094" PBF MILL-MAX, 2501-2-00-80-00-00-07-0 2 1 JP1 4 PIN 0.079 SINGLE ROW HEADER SULLINS, NRPN041PAEN-RC 3 1 XJP1 SHUNT, .079" CENTER SAMTEC, 2SN-BK-G 4 dc2169af 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 VIN1 VEMI SYNC/MODE SS2/TR2 SS1/TR1 GND 5V / 1.5A VOUT1 EN1 GND 4 C6 0.01uF C24 10uF 50V 1210 L4 0.22uH IHLP1212ABERR22M11 C7 0.01uF 0402 10V R5 14.7k 2MHz SYNC/MODE TR/SS2 TR/SS1 FB1 FB1 SW1 SW1 BOOST1 EN/UV1 VIN2 17 28 12 13 14 9 10 8 C13 0.1uF 50V 0402 3 C14 0.1uF 50V 0402 C3 R6 1M 10V L2 2.2uH R7 R9 OPT R8 1M 0 1M R10 1M R4 316K R3 C9 VOUT1 VOUT2 4.7pF XFL4020-222ME 0.1uF 0402 CUSTOMER NOTICE 11 2 26 27 3 4 5 6 22 C11 2.2uF 50V 1206 C5 47uF 10V 1210 VOUT2 VIN2 C27 1uF + E6 E4 PG1 PG2 GND VOUT2 3.3V / 2.5A EN2 GND VIN2 4.1V - 42V 1630 McCarthy Blvd. Milpitas, CA 95035 E14 E12 C19 1uF E13 E11 E10 C18 22uF 63V 63CE22BS LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A Phone: (408)432-1900 www.linear.com CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; TECHNOLOGY Fax: (408)434-0507 HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO LTC Confidential-For Customer Use Only VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED TITLE: SCHEMATIC CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT DUAL 42V SYNCHRONOUS MONOLITHIC PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. C12 1uF PG1 PG2 FB2 FB2 SW2 SW2 SW2 BOOST2 BIAS ENUV2 1 C16 0.1uF 50V 0402 5 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 2 DATE: SIZE 1 LT8616EFE DEMO CIRCUIT 2169A Monday, January 19, 2015 IC NO. SHEET 1 OF 1 4 REV. N/A C23 4.7uF 50V 1206 4 3 JP1 4 Pins 2mm Ctrs. L3 30 ohm MPZ2012S300AT SYNC/MODE BURST MODE 2 1 R2 187k 3.3uH XAL4030-332ME 0.1uF C2 U1 LT8616EFE 16 C15 0.1uF 50V 0402 0 1 STEP-DOWN REGULATOR WITH 6.5µA QUIESCENT CURRENT C26 0.1uF 50V 0402 C8 1M 4.7pF PULSE SKIPPING C4 22uF 10V 1210 R1 L1 R12 OPT R11 1M C10 2.2uF 50V 1206 R13 2 1. ALL RESISTORS ARE IN 0603 ALL CAPACITORS ARE IN 0603 C25 0.1uF 50V 0402 SYNC C17 1uF C28 1uF C1 22uF 63V 63CE22BS VOUT1 + VIN1 3 NOTE: UNLESS OTHERWISE SPECIFIED E16 E7 E8 E9 E5 E3 E15 E2 PAD150-094 E1 20 NC 5.8V - 42V 19 VIN1 D 4 18 NC RT 15 GND 29 23 NC 7 24 VIN2 INTVCC 21 NC 25 NC 5 A B C D DEMO MANUAL DC2169A Schematic Diagram dc2169af 5 DEMO MANUAL DC2169A 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 dc2169af Linear Technology Corporation LT 0515 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2015