DEMO MANUAL DC1632A LTC3839EUH Fast Transient Step-Down DC/DC Converter DESCRIPTION Demonstration circuit 1632A is a single output 1.5V/40A dual phase synchronous buck converter operating with a switching frequency of 300kHz over an input voltage range of 4.5V to 14V. The controlled on-time valley current mode architecture of the LTC3839 allows for a fast load step response (see Figure 4). The load step response can be tested with the on-board load step circuit and a bench pulse generator. Other features of the board include remote sensing, selectable light load operating modes of forced continuous mode (FCM) and discontinuous mode (DCM), a PLLIN pin for synchronizing to an external clock, a CLKOUT pin, an EXTVCC pin to reduce losses in the controller, and PERFORMANCE SUMMARY PARAMETER RUN and TRACK/SS pins. Up to 12-phase operation can be achieved by daisy-chaining the CLKOUT and PLLIN signals of multiple boards and programming the relative phase with the PHASMD jumper. The demo board uses a high density, two sided drop-in layout. The entire converter, excluding the bulk output and input capacitors, fits within a compact 1.6˝ × 1.2˝ area on the board. The package style for the LTC3839EUH is a 32-lead 5mm × 5mm QFN with an exposed ground pad. Design files for this circuit board are available at http://www.linear.com/demo L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. (TA = 25°C) CONDITIONS VALUE Minimum Input Voltage 4.5V Maximum Input Voltage 14V Output Voltage VOUT IOUT = 0A to 40A, VIN = 4.5V to 14V 1.5V ± 2% VOUT Maximum Output Current, IOUT VIN = 4.5V to 14V, VOUT = 1.5V 40A Nominal Switching Frequency Efficiency (see Figures 2 and 3) 300kHz VOUT = 1.5V, IOUT = 40A, VIN = 12V 90.7% Typical dc1632af 1 DEMO MANUAL DC1632A QUICK START PROCEDURE Demonstration circuit 1632A is easy to set up to evaluate the performance of the LTC3839EUH. Please refer to Figure 1 for proper measurement equipment setup and follow the procedure below. 1) With power off, connect the input supply, load and meters as shown in Figure 1. Preset the load to 0A and VIN supply to 0V. Place jumpers in the following positions: JP1 JP3 RUN MODE ON FCM 2) Adjust the input voltage to be between 4.5V and 14V. VOUT should be 1.5V ±2%. 3) Next, apply 40A load and re-check VOUT. 4) Once the DC regulation is confirmed, observe the output voltage ripple, load step response, efficiency and other parameters. Note 1. Use the BNC connector labeled VOUT to measure the output voltage ripple. Load Step Testing (Optional) Demonstration circuit 1632A provides a simple load step circuit consisting of a MOSFET and sense resistor for each rail. To apply a load step, follow the steps below. 1) Pre-set the amplitude of a pulse generator to 0.0V and the duty cycle to 5% or less. 2) Connect the scope to the VOUT BNC connectors for the rail under test with a coax cable. To monitor the load step current, connect the scope probe across the ISTEP± pins. 3) Connect the output of the pulse generator to the PULSE GEN pin and connect the return to the GND pin. 4) With the converter running, slowly increase the amplitude of the pulse generator output to provide the desired load step pulse height. The scaling for the LOAD STEP signal is 5mV/Amp. Note 2. Do not apply the load from the VO_SNS+ pin to the VO_SNS– pin. This may damage the converter. These pins are only intended to monitor the voltage across the bulk output capacitors at COUT1-4. VIN SUPPLY LIN IOUT + + – + VOUT LOAD VIN – – + – VOUT* * MONITOR THE VOLTAGE ACROSS COUT5 FOR ACCURATE EFFICIENCY MEASUREMENTS. Figure 1. Proper Measurement Equipment Setup dc1632af 2 DEMO MANUAL DC1632A QUICK START PROCEDURE LTC3839 1.5V/40A Converter FCM, fSW = 300kHz 95 EFFICIENCY (%) VIN = 5V VIN = 12V 90 85 Qtop = Infineon BSC050NE2LS Qbottom = Infineon BSC010NE2LS L = Coiltronics FP1308R3-R44-R (0.44μH, DCR = 0.18m Ω±20%) RSENSE = 2mΩ 80 75 0 5 10 15 20 25 30 35 40 45 LOAD CURRENT (A) Figure 2. Efficiency Curves for the DC1632A in FCM LTC3839 1.5V/40A Converter FCM & DCM, VIN = 12V, fSW = 300kHz DCM FCM EFFICIENCY (%) 100 90 80 70 60 50 40 30 20 10 0 0.01 Qtop = Infineon BSC050NE2LS Qbottom = Infineon BSC010NE2LS L = Coiltronics FP1308R3-R44-R (0.44μH, DCR = 0.18m Ω±20%) RSENSE = 2mΩ 0.10 1.00 10.00 100.00 LOAD CURRENT (A) Figure 3. Efficiency Curves for the DC1632A in FCM and DCM 20μsec/DIV 1.5V(AC) 50mV/DIV 106mVP-P 40A LOAD STEP 10A/DIV 20A Figure 4. Load Step Response of the DC1632A at VIN = 12V. COUT = 4× Sanyo 2R5TPE330M9 || 2× 100μF X5R 6.3V 1206, L1, 2 = 0.44μH, fSW=300kHz dc1632af 3 DEMO MANUAL DC1632A PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER CAP, X5R 1μF 16V 10% 0603 AVX 0603YD105KAT2A Required Circuit Components 1 2 C13, C5 2 3 C2, C7, C12 CAP, X5R 0.1μF 25V 10% 0603 AVX 06033C104KAT2A 3 2 C3, C11 CAP, X7R 1000pF 16V 0603 AVX 0603YC102KAT2A 4 1 C4 CAP, X5R 4.7μF 16V 10% 0805 AVX 0805YD475KAT2A 5 1 C6 CAP, NPO 68pF 25V 10% 0603 AVX 06033A680KAT2A 6 1 C8 CAP, X7R 470pF 16V 5% 0603 AVX 0603YC471JAT2A 7 1 C9 CAP, X5R 0.01μF 25V 10% 0603 AVX 06033C103KAT2A 8 1 CIN1 CAP, 180μF 16V SANYO 16SVP180MX 9 2 CIN3, CIN4 CAP, X5R 22μF 16V 1210 MURATA GRM32ER61C226KE20L 10 4 COUT1, COUT2, COUT3, COUT4 CAP, 330μF 2.5V SIZE 7343 SANYO 2R5TPE330M9 11 2 COUT6, COUT5 CAP, X5R 100μF 6.3V 1206 MURATA GRM31CR60J107ME 39L 12 2 D1,D2 DIODE, SCHOTTKY SOD-323 CENTRAL SEMI CMDSH-4E TR 13 2 L1,L2 IND, 0.44μH COILTRONICS FP1308R3-R44-R 14 2 Q1,Q3 MOSFET, N CHANNEL POWERPAK SO-8 INFINEON BSC050NE2LS 15 2 Q2,Q4 MOSFET, N CHANNEL POWERPAK SO-8 INFINEON BSC010NE2LS 16 3 R11, R29, R33 RES, CHIP 10k 1% 0603 VISHAY CRCW060310K0FKEA 17 1 R15 RES, CHIP 22.1k 1% 0603 VISHAY CRCW060322K1FKEA 18 1 R13 RES, CHIP 137k 1% 0603 VISHAY CRCW0603137KFKEA 19 2 R14, R12 RES, CHIP 2.2 1% 0603 VISHAY CRCW06032R20FKEA 20 1 R22 RES, CHIP 15k 1% 0603 VISHAY CRCW060315K0FKEA 21 6 R3, R7, R23, R28, R35, R25 RES, CHIP 0 0603 VISHAY CRCW06030000Z0EA 22 1 R32 RES, CHIP 100k 1% 0603 VISHAY CRCW0603100KFKEA 23 6 R4, R5, R17, R19, R26, R27 RES, CHIP 10 1% 0603 VISHAY CRCW060310R0FKEA 24 2 RS1, RS2 RES, CHIP 0.002 1W 1% 2512 VISHAY WSL25122L000FEA 25 1 U1 IC LTC3839EUH QFN 5mm × 5mm LINEAR TECH. LTC3839EUH#PBF Additional Circuit Components 1 0 CIN2 CAP, SVP-F8, OPT 2 0 CIN5, CIN6, CIN7, CIN8 CAP, 1210, OPT 3 0 C1, C10 CAP, 0603, OPT 4 0 COUT9-COUT12 CAP, SIZE 7343, OPT 5 0 Q5-Q8 POWERPAK SO-8, OPT 6 1 Q9 N-Channel MOSFET, TO-252 7 0 R1, R2, R6, R16, R18, R21, R31, R8, R9, R10, R20, R24 RES, CHIP 0603, OPT 8 1 R33 RES, CHIP 10k 1% 0603 VISHAY CRCW060310K0FKEA 9 1 R34 RES, CHIP 0.005 1W 1% 2010 VISHAY WSL20105L000FEA 1 16 E1-E16 TESTPOINT, TURRET .095" MILL-MAX 2501-2-00-80-00-00-07-0 2 1 JP1 2mm SINGLE ROW HEADER 3 PIN SAMTEC TMM-103-02-L-S 3 2 JP3, JP2 2mm SINGLE ROW HEADER 4 PIN SAMTEC TMM-104-02-L-S 4 6 E17-E22 JACK, BANANA KEYSTONE 575-4 5 1 J1 CONN, BNC, 5PINS CONNEX 112404 6 4 (STAND-OFF) STAND-OFF, NYLON 0.25" KEYSTONE 8831 (SNAP ON) VISHAY SUD50N03-12P-E3 Hardware dc1632af 4 A B C D 60 DEG 90 DEG EXTVCC TRK/SS 3 2 R28 0 C13 1uF EXTVCC R11 10K R25 0 R16 OPT R31 OPT C1 OPT OPT R18 5 2. INSTALL SHUNTS ON JUMPERS AS SHOWN. 1. ALL RESISTORS ARE IN OHMS, 0603. ALL CAPACITORS ARE IN MICROFARADS, 0603. NOTES: UNLESS OTHERWISE SPECIFIED PGOOD E10 E7 E6 E5 E4 DCM SYNC FCM E12 CLKOUT MODE JP3 INTVCC 3 2 R1 OPT R2 OPT VIN INTVCC PHASMD JP2 RUN JP1 2 INTVCC 120 DEG PLLIN GND OFF ON 3 1 5 C9 0.01uF 8 7 6 5 4 VOUT VOUTSENSE+ TRACK/SS ITH RT SGND CLKOUT MODE/PLLIN PHASEMD R6 OPT ISTEP+ ISTEPLOAD STEP 5mV / A 5% DUTY CYCLE MAX R29 10K R22 15K C8 470pF C10 OPT R15 22.1K C6 68pF R13 137K FSW = 300kHz 3 2 1 U1 LTC3839EUH R3 0 INTVCC S2+ E16 E15 R4 10 C3 1nF R5 10 S2- S1- R32 100K R33 10K 4 BG1 DRVCC1 VIN PGND INTVCC EXTVCC DRVCC2 BG2 E14 E13 GND PULSE GEN 17 18 19 20 21 C4 4.7uF 16V 0805 VOUT 3 OPT 7343-D15T COUT9 OPT 7343-D15T +COUT11 + 4 COUT12 OPT 7343-D15T + Q1 OPT 7343-D15T +COUT10 4 4 4 INFINEON BSC050NE2LS 4 INFINEON BSC010NE2LS Q2 4 R14 2.2 OPTIONAL COUT C7 0.1uF C5 1uF INFINEON BSC010NE2LS Q4 23 EXTVCC 22 4 Q3 INFINEON BSC050NE2LS 4 R12 2.2 INTVCC 3 24 CMDSH-3 CMDSH-3 D2 INTVCC D1 Q9 SUD50N03-12P 1 R34 0.005 2010 VOUT 0.1uF C12 0.1uF R23 0 0 R7 C2 LOAD STEP CIRCUIT 1 R35 0 GND R26 R27 10 10 C11 1nF SGND S1+ J1 4 29 SGND E1 28 RUN 1 4 1 4 32 VRNG VOUTSENSE- 9 30 SENSE2+ SENSE1+ 31 SENSE2SENSE111 DTR 12 27 BOOST2 BOOST1 14 PGOOD 13 3 10 5 4 3 2 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. 2 25 TG2 26 SW2 TG1 15 SW1 16 5 6 7 8 1 2 3 5 6 7 8 1 2 3 PGND 33 5 6 7 8 1 2 3 5 6 7 8 1 2 3 5 6 7 8 1 2 3 CIN4 22uF 16V 1210 0.44uH L2 R8 OPT CIN6 OPT 1210 CIN3 22uF 16V 1210 0.44uH L1 R20 OPT CIN5 OPT 1210 S1- R24 OPT R21 OPT S1+ S2- R10 OPT R9 OPT S2+ 2 0.002 2512 RS1 0.002 2512 RS2 2 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. R17 10 CIN8 1210 OPT HZ SCALE = NONE MIKE S. VIN- GND TECHNOLOGY E11 E9 E8 MIKE S. APPROVED DATE 11-8-11 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only GND VO_SNS- VO_SNS+ E22 GND 330uF 2.5V 7343-D15T E21 VOUT E20 1.5V / 40A E19 E3 VIN+ VIN 4.5V - 14V E18 E17 E2 PRODUCTION LTC3839EUH 1 DEMO CIRCUIT 1632A Tuesday, January 10, 2012 IC NO. SHEET 1 OF 1 2 REV. FAST TRANSIENT STEP-DOWN DC/DC CONVERTER DATE: N/A SIZE 1 DESCRIPTION REVISION HISTORY +COUT1 VOUT 330uF 2.5V 7343-D15T +COUT2 180uF 16V +CIN1 TITLE: SCHEMATIC R19 10 VIN 2 REV OPT SANYO-F8 +CIN2 __ ECO 330uF 2.5V 7343-D15T CIN7 1210 OPT +COUT3 APPROVALS COUT5 100uF 6.3V 1206 330uF 2.5V 7343-D15T +COUT4 COUT6 100uF 6.3V 1206 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. CUSTOMER NOTICE OPTIONAL DCR SENSE FILTER / DIVIDER FOR PHASE 1 Q6 OPT Q5 OPT OPTIONAL DCR SENSE FILTER / DIVIDER FOR PHASE 2 Q8 OPT Q7 OPT 5 6 7 8 1 2 3 5 6 7 8 1 2 3 5 6 7 8 1 2 3 RUN A B C D DEMO MANUAL DC1632A SCHEMATIC DIAGRAM dc1632af 5 DEMO MANUAL DC1632A 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 dc1632af 6 Linear Technology Corporation LT 0212 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2012