DC2431A AD | Alldatasheet
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 8
Technical content
DESCRIPTION
High Power Synchronous 4-Switch Buck- Boost Regulator with Spread Spectrum Demonstration circuit 2431A is a 4-switch synchronous buck-boost regulator that demonstrates the high power capability of the LT®8390. The output is 12V and the maximum output current is 25A for up to 300W power delivery. The switching frequency is 150kHz and efficiency can go higher than 98%. The operating input voltage range of DC2431A is from 9V to 36V. The output voltage and EN/UVLO are all programmed by resistor dividers. EN/UVLO is set so the circuit will turn off when the input voltage falls below 9V and will turn on when the input voltage rises above 10V. DC2431A features MOSFETs that complement the 5V gate drive of the LT8390 to achieve high efficiency. 40V MOSFETs are used on the input side of the four-switch topology while 25V MOSFETs are used on the output side. Ceramic capacitors are used at both the circuit input and output because of their small size and high ripple current capability. In addition to ceramic capacitors, there are four bulk aluminum polymer capacitors on the output. The input has four aluminum polymer capacitors. The PCB has large copper planes and extensive vias for excellent high power thermal performance. There are four mounting holes on the board for optional heat sink and fan, which can push the output power of DC2431A up to 480W. For more details, please consult the factory for assistance. The CTRL input is pulled up to the V REF pin through a 0Ω resistor to set the output current limit to its maximum, and an external voltage on CTRL can be used to lower the current limit if the resistor is removed. A capacitor at the SS pin programs soft-start. L, L T , L TC, L TM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. To improve the EMI performance, the LT8390 has spread spectrum frequency modulation. With the SYNC/SPRD pin tied to INTV CC, LT8390 starts to spread its switch - ing frequency ±15% around the programmed oscillator frequency. The PGOOD status flag indicates when output voltage is within ±10% of final regulation voltage. The LT8390’s proprietary peak current mode buck-boost architecture ensures DC2431A runs either in discontinuous conduction mode (DCM) or pulse-skipping mode (PSM) without reversed inductor current. Both of them enhance the light load efficiency. The demo circuit is designed to be easily reconfigured to many other applications, including the example schemat- ics in the data sheet. Consult the factory for assistance. High power operation, 4-switch buck-boost topology, proprietary peak current mode architecture, fault protec- tion and full monitoring make the LT8390 attractive for high power voltage regulator circuits and also circuits that require output current regulation such as battery chargers. The LT8390EFE is available in a thermally enhanced 28 -lead TSSOP package. The LT8390 data sheet must be read in conjunction with this demo manual to properly use or modify demo circuit DC2431A. Design files for this circuit board are available at http://www.linear .com/demo/DC2431A
PERFORMANCE SUMMARY Specifications are at TA = 25°C PARAMETER CONDITIONS MIN TYP MAX Input Voltage Range (VIN) VOUT = 12V, IOUT ≤ 25A 9VDC 36VDC Output Voltage (VOUT) R7 = 110k, R8 = 10k 11.5VDC 12.0VDC 12.5VDC Maximum Output Current 9V ≤ VIN ≤ 36V, VOUT = 12V 25A Switching Frequency R5 = 309k 150kHz Efficiency VIN = 12V, VOUT = 12V, IOUT =10A 98% Input EN Voltage R9 = 365k, R10 = 56.2k 10VDC Input UVLO Voltage R9 = 365k, R10 = 56.2k 9VDC Output Current Limit R3 = R4 = 6mΩ 33A
Figure 1. Test Procedure Setup Drawing for DC2431A ment equipment setup and follow the procedure below.
- Set JP1 at NO SSFM/SYNC to disable SSFM, or at SSFM
- Connect the EN/UVLO terminal to ground with a clip-on
- After all connections are made, turn on the input power
and verify that the input voltage is between 9V and 36V.
- Remove the clip-on lead from EN/UVLO. Verify that the
nect the load to make sure that it is not set too high.
- Once the proper output voltage is established, adjust
age, efficiency and other parameters.
Figure 5. Temperature Rise at Worst Case (VIN = 9.5V, VOUT = 12V, IOUT = 25A)
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER 31 1 R5 RES., 309k, 1/10W, 1%, 0603 VISHAY, CRCW0603309KFKEA 32 1 R6 RES., 15k, 1/10W, 1%, 0603 VISHAY, CRCW060315K0FKEA 33 1 R7 RES., 110k, 1/10W, 1%, 0603 VISHAY, CRCW0603110KFKEA 34 1 R8 RES., 10k, 1/10W, 1%, 0603 VISHAY, CRCW060310K0FKEA 35 1 R9 RES., 365k, 1/10W, 1%, 0603 VISHAY, CRCW0603365KFKEA 36 1 R10 RES., 56.2k, 1/10W, 1%, 0603 VISHAY, CRCW060356K2FKEA 37 1 R11 RES., 100k, 1/10W, 1%, 0603 VISHAY, CRCW0603100KFKEA 38 2 R12, R13 RES., 10Ω, 1/10W, 1%, 0603 VISHAY, CRCW060310R0FKEA 43 1 U1 I.C., VOL TAGE REGULATOR, 28-TSSOP LINEAR TECH., LT8390EFE#PBF Optional Electronic Components 39 7 R14, R15, R16, R17, R18, R19, R20 RES., 0Ω, 1/10W, 0603 VISHAY, CRCW06030000Z0EA 40 0 R21, R22, R23, R24, R25, R26 (OPT) RES., OPTION, 0603 41 0 R27 (OPT) RES., OPTION, 1225 42 0 R28, R29 (OPT) RES., OPTION, 0805 11 0 C26, C27, C28 (OPT) CAP ., OPTION, 0603 12 0 C29, C30 (OPT) CAP ., OPTION, 0805 13 0 C31, C32, C33, C34 (OPT) CAP ., OPTION, ALUM 28 0 M9, M10 (OPT) XSTR., MOSFET , OPTION, TDSON-8 14 0 D1, D2 (OPT) DIODE., OPTION, SMB Hardware 15 11 E1, E2, E3, E4, E5, E6, E7, E8, E9, E10, E11 TEST POINT , TURRET , .094 MTG. HOLE MILL-MAX, 2501-2-00-80-00-00-07-0 16 1 JP1 CONN., HEADER, 2 × 3, 2mm WURTH ELEKTRONIK, 62000621121 17 1 XJP1 SHUNT , 2mm WURTH ELEKTRONIK, 60800213421 18 4 J1, J2, J3, J4 CONN., JACK, BANANA, 0.218 KEYSTONE, KEY-575-4 19 4 J5, J6, J7, J8 STUD, TEST PIN PEM KFH-032-10 20 8 (J5, J6, J7, J8) NUT , BRASS NUTS # 10-32 ANY #10-32 21 4 (J5, J6, J7, J8) RING, LUG RING # 10 KEYSTONE #10 22 4 (J5, J6, J7, J8) WASHER, TIN PLATED BRASS ANY #10 PARTS LIST
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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. SCHEMATIC DIAGRAM VIN 9V - 36V EN/UVLO GND GND ALL CAPACITORS ARE 0603. NOTE: UNLESS OTHERWISE SPECIFIED 150kHz ALL RESISTORS ARE 0603. 12V OUT PGOOD ISMON GND LOADEN 25A CTRL VIN + C19 180uF 50V 0.1uF C14 47uF 1210 16V 1uF 100V 0805 C10 10uF 1210 50V C15 47uF 1210 16V 15K +C22 560uF 16V 16HVH560M R12 0.006 1225 KRL6432E-C-R006-F-T5 1 3 2 4 R29 OPT 0805 LT8390EFE EN/UVLO9 PGOOD17 TEST10 CTRL13 LOADEN11 ISP 14 SYNC/SPRD22 SS 18 LOADTG23 VC 20 RT 21 VREF12 ISMON16 LSN 6 LSP 5 ISN 15 FB 19 TG2 25 SW2 26 BG2 28 BG1 1 SW1 3 TG1 4 BST1 2 BST2 27 VIN7 INTVCC8 GND 29 VOUT 24 R19 JP1 SSFM ON EXT SYNCEXT SYNC NO SYNC/SSFM SYNC/SSFM 309K BSC014N04LSI R4 0.006 1225 R13 0.1uF R26 OPT +C33 OPT R23 OPT R21 OPT R7 110K R11 100K R25 OPT J4C2 4.7uF 10V R15 C11 10uF 1210 50V C30 OPT 0805 1uF 25V R14 BSC015NE2LS5I C29 OPT 0805 C24 560uF 16V 16HVH560M 0.002 1225 BSC014N04LSI E10 OPT R22 OPT C13 47uF 1210 16V R24 OPT C12 10uF 1210 50V + C31 OPT C25 1uF +C18 180uF 50V R16 BSC010N04LSI M3 BSC015NE2LS5I +C23 560uF 16HVH560M 16V 0.47uF C16 47uF 1210 16V 0.002 1225 KRL6432E-M-R002-G-T1 1 3 2 4 R18 +C34 OPT + C32 OPT R10 56.2K 10uF 1210 50V + C20 180uF 50V M10 OPT C27 OPT R17 E11 C26 OPT SER2915L-332KL COILCRAFT 3.3uH BSC009NE2LS5I 10K +C21 560uF 16V 16HVH560M C28 OPT 0.1uF D2 OPT R28 OPT 0805 365K OPT +C17 180uF 50V 15nF R20 R27 OPT 1225 ISP ISN INTVCC INTVCC VREF VIN LOADTG LOADTG ISP ISN VREF
DEMO MANUAL DC2431A Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear .com © LINEAR TECHNOLOGY CORPORATION 2016 LT 1016 • PRINTED IN USA 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