DESCRIPTION Demonstration circuit DC88A features the LTM 6EV, a low input voltage A step-down power module. The operating input voltage range is.v to.v with an output voltage range from 0.8V to V. DC88A can support a load current up to A, while derating may be necessary for different V IN, V OUT and thermal conditions. The LTM6EV can operate in pulse-skipping mode or Burst Mode operation for high effi ciency under a light load. The DC88A has a default programmable switching frequency of 00kHz and may be synchronized to an external clock from 60kHz up to 70kHz. The TRACK/SS input allows the output voltage to ramp up and ramp down; coincidentally or ratiometrically with an external voltage. A remote PERFORMANCE SUMMARY (T A = C) DEMO MANUAL DC88A LTM6EV: Ultralow V IN A Step-Down Power µmodule Regulator output voltage sense feature improves the output voltage accuracy under high loads. These features and the availability of the LTM6EV in a compact mm mm.mm LGA package make the demonstration circuit ideal for use in many high density point-of-load regulation applications. The LTM6 data sheet must be read in conjunction with this demo manual for working on or modifying the demo circuit 88A. Design fi les 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. PARAMETER CONDITIONS VALUE Input Voltage Range.V to.v Output Voltage V OUT Selectable with Jumpers (Open for 0.8V) 0.8V,.0V,.V,.V,.8V,.V,.V Maximum Continuous Output Current Derating is Necessary for Certain Operating Conditions. A DC See Data Sheet for Details Default Operating Frequency 00kHz External Clock Synchronous Frequency Range 60kHz to 70kHz Efficiency V IN = V, V OUT =.V, I OUT = A 9%, See Figure BOARD PHOTO dc88af
DEMO MANUAL DC88A QUICK START PROCEDURE Demonstration circuit 88A is easy to set up to evaluate the performance of the LTM6EV. Please refer to Figure for proper measurement equipment setup and follow the procedure below:. Place jumpers in the following positions for a typical.8v OUT application: JP JP JP JP V OUT SELECT MODE/PLLIN TRACK/SS.8V ON FCM SS. With power off, connect the input power supply, load and meters as shown in Figure. Preset the load to 0A and V IN supply to be V.. Turn on the power supply at the input. The output voltage should be.8v ±.%.. Once the proper output voltage is established, adjust the load within the operating range and observe the output voltage regulation, output voltage ripple, effi ciency and other parameters. Output ripple should be measured at J with a BNC cable.. To perform a load transient test, apply a square-wave pulse signal between IOSTEP_CLK and GND pins. The pulse amplitude (V ~.V) sets the amplitude of load current step. The pulse signal should have very small duty cycle (<0%) to limit the thermal stress on the transient load circuit. The output transient current can be monitored at BNC connector J6 (mv/a). 6. The LTM6 can be synchronized to an external clock signal. Place the jumper JP in the EXTCLK position and apply the clock signal on the CLKIN (TP7) test point. 7. The output of LTM6 can track another supply. The jumper JP allows selection of the soft-start or output tracking feature. If tracking external voltage is selected, the corresponding test point, TRACK (TP7), needs to be connected to a valid reference voltage signal. V A V IN.V TO.V V A LOAD 0A TO A DC88A F0 Figure. Test Setup of DC88A dc88af
DEMO MANUAL DC88A QUICK START PROCEDURE Effi ciency vs Load Current at.v IN, Forced Continuous Mode Effi ciency vs Load Current at V IN, Forced Continuous Mode 9 9 90 90 EFFICIENCY (%) 8 EFFICIENCY (%) 8 80 7 0.V OUT.8V OUT.V OUT.V OUT.0V OUT 0.9V OUT 0.8V OUT 6 9 OUTPUT CURRENT (A) 80 7 0.V OUT.V OUT.8V OUT.V OUT 6 9 OUTPUT CURRENT (A).V OUT.0V OUT 0.9V OUT 0.8V OUT DC88A F0a DC88A F0b Figure. Measured Supply Effi ciency with Different V IN and V OUT V OUT 0mV/DIV I OUT 6.A/DIV V IN = V 0μs/DIV V OUT =.V 0A TO 7A LOAD STEP C OUT = 00μF CERAMIC, C7 = 0.μF DC88 F0 Figure. Measured Load Transient Response (0A to 7A Step) dc88af
DEMO MANUAL DC88A PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components CIN CAP, 0μF 0% 6V OS-CON SANYO OS-CON 6SVP0M CIN, CIN CAP, 0 7μF 0% 6V XR TAIYO YUDEN EMKBJ76MM-T CO, CO, CO, CO6 CAP, 0 00μF 0% 6.V XR AVX 06D07MATA R9, R0 RES, 060 0Ω % /0W VISHAY CRCW0600R0JNEA R RES, 060 8.7k % /0W VISHAY CRCW0608K7FKEA 6 C CAP, 060 7pF 0% 0V NPO AVX 060A70KAT 7 U IC, HIGH EFFICIENCY STEP-DOWN MODULE LINEAR TECH.LTM6EV Additional Demo Board Circuit Components 0 CIN CAP, 0 μf 0% 6V XR ION TDK CXRC6M ION 0 CO CAP, 7 0μF 0% V POSCAP ION SANYO POSCAP TPE0MI ION 0 CO CAP, 0 00μF 0% 6.V XR ION AVX 06D07MATA ION 0 C CAP, 060 0pF 0% 0V NPO ION AVX 060AKAT ION C CAP, 060.7μF 0% 0V XR TAIYO YUDEN LMK07BJ7MA-T 6 0 C,C6 CAP, 060 ION ION 7 C CAP, 060 0nF 0% 0V X7R TDK C608X7RH0K 8 C7 CAP, 060 0.μF 0% 6V X7R TAIYO YUDEN EMK07BJ0MA-T 9 0 C8 CAP, 080 ION ION 0 0 D DIODE, ZENER 0mW ION DIODES INC. BZX8CV6 ION Q XSTR, MOSFET VISHAY SILICONIX SUD0N0-09P-E RS RES, 0.0Ω % W PANASONIC ERJMWSFMU 0 R,R-R, R8, R, R RES, 060 ION ION R RES, 060 k % /0W VISHAY CRCW060KFKEA R RES, 060 k % /0W VISHAY CRCW060KFKEA 6 R RES, 060 69.8k % /0W VISHAY CRCW06069K8FKEA 7 R6 RES, 060 8.7k % /0W VISHAY CRCW0608K7FKEA 8 R7 RES, 060 9.k % /0W VISHAY CRCW0609KFKEA 9 R, R RES, 060 0k % /0W VISHAY CRCW0600K0JNEA 0 R7 RES, 060 60.k % /0W VISHAY CRCW06060KFKEA R9 RES, 060 00k % /0W VISHAY CRCW06000KJNEA R RES, 060 0Ω JUMPER VISHAY CRCW0600000Z0EA Hardware JP, JP HEADER, PIN, mm SAMTEC TMM-0-0-L-S JP HEADER, MM DOUBLE R0W, X SAMTEC TMM-0-0-L-D JP HEADER, MM DOUBLE R0W, X7 SAMTEC TMM-07-0-L-D J, J, J, J JACK, BANANA KEYSTONE 7- J, J6 CONN, BNC, PINS CONNEX 0 6 TP, TP, TP, TP, TP8 TURRET MILL MAX 0--00-80-00-00-07-0 7 TP, TP7, TP, TP, TP7 TURRET MILL MAX 08--00-80-00-00-07-0 8 XJP, XJP, XJP, XJP SHUNT, mm SAMTEC SN-BK-G 9 STANDOFF, SNAP ON KEYSTONE_88 dc88af
DEMO MANUAL DC88A SCHEMATIC DIAGRAMS.V -.V GND 0uF 6V 7uF 7uF 6V 6V 6V 0 0 0 - JP ON CLKIN EXTCLK PULSE_SKIP BURST MODE FCM TRACK R7 60.K TRACK TRACK/SS SS PGOOD REVISION HISTORY ECO REV DESCRIPTION APPROVED DATE PRODUCTION JEFF Z. 0//0 DYNAMIC LOAD CIRCUIT C.7uF IOSTEP_CLK IOSTEP CO CO CO 00uF 00uF 00uF 6.V 6.V 6.V 0 0 0 J C7 0.uF VO SHT R9 0 TP VO J CO CO6 0.8V -.V 00uF @A 0 6.V 0 J VO SHT SHT 0.8V SELECT.0V.V.V.8V.V.V TECHNOLOGY HIGH EFFICIENCY ULTRA-LOW A STEP-DOWN POWER MODULE R LTM6EV DEMO CIRCUIT 88A Thursday, May, 00 R R TP U LTM6EV A A A A A A6 B B B B B B6 C C C C C C6 G H H VOSNS GND VO- VO- SHT < VO- VOSNS- J M B7 B9 C7 C9 D D D D D D6 D8 E E E E E E6 E7 E9 F F F F F F6 F7 F8 F9 G G G G G G6 G7 G8 G9 H H H H H H6 H7 H8 H9 J J J J J J6 J7 J8 J9 J0 K K K K K K6 K7 K8 K9 K0 K TP JP 6 7 8 A0 A B A8 A9 A7 D9 F G COMP FSET MODE/PLLIN TRACK/SS L L L L L L6 L7 L8 L9 L0 L M M M M M M6 M7 M8 M9 M0 M C8 _LCL DIFF_ L K R 0 PGOOD PGOOD VFB F MTP MTP MTP MTP MTP MTP6 MTP7 MTP8 MTP9 A B C0 C C D0 D D E C JP 6 9 7 8 0 TP TP7 R8 JP Q SUD0N0-09P-E J6 J CIN CIN CIN CIN J TP R 0k OFF D R C TP7 C6 R9 00K TP RS 0.0 % R 0k CO C 0nF TP8 R R0 0 TP R C 7pF R R R R R R6 R7 K K 69.8K 8.7K 8.7K 9.K % % % % % % 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. dc88af
DEMO MANUAL DC88A 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 0 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 60 McCarthy Blvd. Milpitas, CA 90 Copyright 00, Linear Technology Corporation 6 LT 00 PRINTED IN USA Linear Technology Corporation 60 McCarthy Blvd., Milpitas, CA 90-77 (08) -900 FAX: (08) -007 www.linear.com LINEAR TECHNOLOGY CORPORATION 00 dc88af