ADP2389-EVALZ/ADP2390-EVALZ User Guide UG-863 One Technology Way * P.O. Box 9106 * Norwood, MA 02062-9106, U.S.A. * Tel: 781.329.4700 * Fax: 781.461.3113 * www.analog.com Evaluating the ADP2389/ADP2390, 18 V, 12 A Step-Down Regulators with Programmable Current Limit FEATURES GENERAL DESCRIPTION Input voltage: 4.5 V to 18 V Continuous output current: 12 A Integrated MOSFET: 17 m/4.5 m Reference voltage: 0.6 V 0.5% Programmable switching frequency: 200 kHz to 2.2 MHz Enhanced transient response Programmable current-limit with 10% accuracy Precision enable and power good External compensation and soft start PFM mode (ADP2390 only) Start up into a precharged output Supported by ADIsimPower design tool The ADP2389/ADP2390 evaluation board is a complete, 12 A, 18 V, step-down regulator solution that allows users to evaluate the performance of the ADP2389/ADP2390 with a near ideal printed circuit board (PCB) layout. The programmable current-limit function allows the inductor to be optimized by output current. The peak current-limit threshold is preset to 16.8 A to ensure the 12 A output current capability. The switching frequency can be programmed between 200 kHz and 2.2 MHz, which provides the possibility for a stackable multiphase power solution. TM An enhanced transient response feature improves the load transient performance, which reduces the output capacitance. The output of the ADP2389/ADP2390 evaluation board is preset to 1.8 V and the switching frequency is set to 500 kHz. Different output voltage settings can be achieved by changing appropriate passive components. The ambient temperature operating range is -40C to +85C. Full details on the ADP2389/ADP2390 regulators are provided in the ADP2389/ADP2390 data sheet, available from Analog Devices, Inc., which should be consulted in conjunction with this user guide. 13375-001 EVALUATION BOARD PHOTOGRAPH Figure 1. PLEASE SEE THE LAST PAGE FOR AN IMPORTANT WARNING AND LEGAL TERMS AND CONDITIONS. Rev. 0 | Page 1 of 8 UG-863 ADP2389-EVALZ/ADP2390-EVALZ User Guide TABLE OF CONTENTS Features .............................................................................................. 1 Measuring Evaluation Board Performance ...................................3 General Description ......................................................................... 1 Modifying the Board .....................................................................4 Evaluation Board Photograph ......................................................... 1 Evaluation Board Schematic and Artwork.....................................5 Revision History ............................................................................... 2 Ordering Information .......................................................................7 Evaluation Board Hardware ............................................................ 3 Bill of Materials ..............................................................................7 Power Supplies .............................................................................. 3 REVISION HISTORY 9/15--Revision 0: Initial Version Rev. 0 | Page 2 of 8 ADP2389-EVALZ/ADP2390-EVALZ User Guide UG-863 EVALUATION BOARD HARDWARE POWER SUPPLIES Turning On the Evaluation Board The ADP2389/ADP2390 evaluation board is provided fully assembled and tested. Before applying power to the evaluation board, follow the procedures in this section. When the power source and load are connected to the evaluation board, it can be powered for operation. Jumper J5 (Enable) 1. 2. 3. Perform the following steps to turn on the board: Use one of the following methods to enable or to disable the regulator: * * To enable the regulator, short the middle pin of J5, EN, to high. To disable the regulator, short the middle pin of J5, EN, to low. Ensure that the power source voltage is >4.5 V and <18 V. Ensure that EN is high and monitor the output voltage. Turn on the load, check that it is drawing the proper load current, and verify that the output voltage maintains its regulation. MEASURING EVALUATION BOARD PERFORMANCE Measuring the Switching Waveform Input Power Source If the input power source includes a current meter, use that meter to monitor the input current. Connect the positive terminal of the power source to J7 (PVIN) of the evaluation board, and the negative terminal of the power source to J14 (GND) of the evaluation board. If the power source does not include a current meter, connect a current meter in series with the input source voltage. Connect the positive lead (+) of the power source to the positive (+) ammeter terminal, the negative lead (-) of the power source to J14 (GND), and the negative lead (-) of the ammeter to J7 (PVIN). Output Load Prior to connecting the load, ensure that the evaluation board is turned off. Connect an electronic load or resistor to the output of the evaluation board to set the load current. Connect the positive terminal of the load to J12 (VOUT) of the evaluation board and connect the negative terminal of the load to J15 (GND). Input and Output Voltmeters Measure the input and output voltages using voltmeters. Ensure that the voltmeters are connected to the appropriate terminals of the evaluation board and not to the load or power source. If the voltmeters are not connected directly to the evaluation board, it produces incorrect measured voltages because the voltage drops across the leads or connections between the evaluation board, the power source, and the load. To measure the input voltage, connect the positive terminal of the voltmeter to J9 (PVIN_SNS) and the negative terminal to J13 (GND_SNS). Likewise, to measure the output voltage, connect the positive terminal of the voltmeter to J11 (VOUT_SNS) and the negative terminal to J16 (GND_SNS). To observe the switching waveform with an oscilloscope, place the oscilloscope probe tip at Test Point J3 (SW) with the probe ground at J1 (GND). Set the scope to dc with the appropriate voltage and time divisions. Alternate the switching waveform limits between ~0 V and the input voltage. Measuring Load Regulation Measure the load regulation by observing the change in the output voltage while increasing the output load current. To minimize the voltage drop, use short, low resistance wires. Measuring Line Regulation Measure the line regulation by varying the input voltage and examining the change in the output voltage with a fixed output current. Line Transient Response To test the line transient response, generate a step input voltage change and observe the behavior of the output voltage using an oscilloscope. Load Transient Response To test the load transient response, generate a load current transient at the output and observe the output voltage response using an oscilloscope. Attach the current probe to the wire between the output and the load to capture the current transient waveform. Measuring Efficiency The efficiency, , is measured by comparing the input power with the output power. = VOUT x I OUT V IN x I IN Measure the input and output voltages as close as possible to the input and output capacitors to reduce the effect of voltage drop. Measuring Inductor Current To measure the inductor current, remove one end of the inductor from its pad and connect a current loop in series with the inductor end and its pad (acurrent probe can be connected onto this wire). Rev. 0 | Page 3 of 8 UG-863 ADP2389-EVALZ/ADP2390-EVALZ User Guide Measuring Output Voltage Ripple To observe the output voltage ripple, place the oscilloscope probe across the output capacitor with the probe ground lead connected to the negative (-) capacitor terminal and the probe tip placed at the positive (+) capacitor terminal. Set the oscilloscope to ac, 10 mV/division, 2 s/division time base, and 20 MHz bandwidth. A standard oscilloscope probe has a long wire ground clip. For high frequency measurements, this ground clip picks up high frequency noise and injects it into the measured output ripple. Figure 2 shows an easy way to measure the output ripple properly. It requires removing the oscilloscope probe sheath and wrapping an unshielded wire around the oscilloscope probe. By keeping the ground length of the oscilloscope probe as short as possible, the true ripple can be measured. To limit output voltage accuracy degradation due to the FB pin bias current (0.1 A maximum) to less than 0.5% (maximum), ensure that the bottom divider string resistor, R5, is less than 30 k. The top resistor, R9, value is calculated using the following equation: V - 0.6 V R9 = R5 x OUT 0.6 V When the output voltage is changed, the values of the inductor (L1), the output capacitors (C13, C14, C15, C16, and C17), and the compensation components (R10, C5, and C4) must be recalculated and changed to ensure stable operation (see the ADP2389/ADP2390 data sheet for details on external component selection). Changing the Switching Frequency The switching frequency (fSW) setpoint can be changed by replacing the R6 resistor with a different value, as shown in the following equation: fSW (kHz) = 67,000/(R6 (k) +12) A 210 k resistor sets the frequency to 300 kHz, and a 100 k resistor sets the frequency to 600 kHz. 13375-002 When the switching frequency is changed, the values of the inductor (L1), the output capacitors (C13, C14, C15, C16, and C17), and the compensation networks (R10, C5, and C4) must be recalculated and changed for stable operation (see the ADP2389/ADP2390 data sheet for details on external component selection). Figure 2. Measuring Output Voltage Ripple MODIFYING THE BOARD To modify the ADP2389/ADP2390 evaluation board configuration, unsolder and/or replace or remove the appropriate passive components or jumpers on the board. Changing the Output Voltages The output voltage setpoints of the ADP2389/ADP2390 can be changed by replacing the R9 and R5 resistors with the resistor values shown in Table 1. Table 1. Resistive Divider for Various Output Voltages VOUT (V) 1.0 1.2 1.5 1.8 2.5 3.3 5.0 R9, 1% (k) 10 10 15 20 47.5 10 22 R5, 1% (k) 15 10 10 10 15 2.21 3 Changing the Soft Start Time The soft start time of the ADP2389/ADP2390 on the evaluation board is programmed to 4 ms. To change the soft start time, tSS, replace the C3 capacitor value using the following equation: C3 (nF) = 5.67 x tSS (ms) Changing the Peak Current-Limit Threshold The peak current-limit threshold of ADP2389/ADP2390 can be changed by replacing the R7 resistor with a different value, as shown in the following equation: IOCP (A) = 1000/(R7 (k) + 0.5) A 54.9 k resistor sets the current-limit threshold to 18 A, an 82.5 k resistor sets the current-limit threshold to 12 A, and a 110 k resistor sets the current-limit threshold to 9 A. By programming the peak current-limit threshold at different levels, the value and size of the inductor (L1) can be optimized based on actual applications. Rev. 0 | Page 4 of 8 1 1 2 3 4 1 EN J5 GND J14 1 2 3 1 2 3 4 GND_SNS J13 PVIN_SNS J9 PVIN J7 R3 NC R1 NC C11 C10 C9 C8 C12 R2 10k 29 32 31 4 30 28 27 22 23 24 25 26 FTW RT ILIM VREG PGOOD EN VIN PVIN1 PVIN2 PVIN3 PVIN4 PVIN5 U1 VIN = 12V, VOUT = 1.8V, IOUT = 12A, fSW = 500kHz C6 1uF 1 PGOOD J2 C1 0.1uF 59k R7 Rev. 0 | Page 5 of 8 121k 10uF/25V R6 10uF/25V NC 10uF/25V R4 10uF/25V 10uF/25V PGND1 PGND2 PGND3 PGND4 PGND5 PGND6 PGND7 SS COMP FB SW1 SW2 SW3 SW4 SW5 SW6 SW7 SW8 SW9 BST 1 2 3 6 7 8 9 10 11 20 34 19 21 C3 22nF R12 6.8R C18 NC R8 NC 1 C5 1.5nF R10 27.4k C7 0.1uF J3 SW C4 22p 1 L1 1uH C2 NC R9 20k C14 C13 R5 10k 2 100uF/6.3V 100uF/6.3V 12 13 14 15 16 17 18 C17 C16 C15 100uF/6.3V 5 33 GND1 GND2 100uF/6.3V 100uF/6.3V Figure 3. Evaluation Board Schematic for ADP2389/ADP2390 GND J4 GND J1 J8 LOOPA 1 ADP2389/ADP2390 1 1 R11 0R 1 GND J6 1 J10 LOOPB 1 2 3 4 1 1 1 2 3 4 GND J15 GND_SNS J16 VOUT_SNS J11 VOUT J12 ADP2389-EVALZ/ADP2390-EVALZ User Guide UG-863 EVALUATION BOARD SCHEMATIC AND ARTWORK 13375-003 ADP2389-EVALZ/ADP2390-EVALZ User Guide Figure 4. Layer 1, Component Side 13375-005 13375-004 UG-863 Figure 5. Layer 2, Ground Plane 13375-007 13375-006 Figure 6. Layer 3, Power Plane Figure 7. Layer 4, Bottom Side Rev. 0 | Page 6 of 8 ADP2389-EVALZ/ADP2390-EVALZ User Guide UG-863 ORDERING INFORMATION BILL OF MATERIALS Table 2. ADP2389 Bill of Materials Qty. 2 2 1 1 1 1 5 5 1 Reference Designator C1, C7 C2, C18 C3 C4 C5 C6 C8, C9, C10, C11, C12 C13, C14, C15, C16, C17 L1 4 2 1 1 1 1 1 1 1 R1, R3, R4, R8 R2, R5 R6 R7 R9 R10 R11 R12 U1 11 J1, J2, J3, J4, J6, J8, J9, J10, J11, J13, J16 1 4 J5 J7, J12, J14, J15 Description 0.1 F, 16 V, capacitor, 0603 Optional, capacitor, 0603 22 nF, 16 V, capacitor, 0603 22 pF, 50 V, capacitor, 0603 1.5 nF, 25 V, capacitor, 0603 1 F, 16 V, capacitor, 0603 10 F, 25 V, capacitor, 1206 100 F, 6.3 V, capacitor, 1210 Inductor, 7443320100, L = 1 H, ISAT = 32 A, DCR = 1.17 m Optional, resistor, 0603 10 k, 1%, resistor, 0603 121 k, 1%, resistor, 0603 59 k, 1%, resistor, 0603 20 k, 1%, resistor, 0603 27.4 k, 1%, resistor, 0603 0 , 0.1 W, resistor, 0603 6.8 , 1%, resistor, 0603 18 V, 12 A, synchronous, step-down regulator, 32-lead, LFCSP_VQ, with exposed paddles Test point, 2.54 mm pitch SIL vertical PC tail pin header, 6.1 mm mating pin height, tin, SIP1 Jumper, 0.1-inch header, three-way, SIP3 Terminal screw vertical PC mount Rev. 0 | Page 7 of 8 Part Number/Vendor GRM188R71C104KA01D/Murata Optional/Murata GRM188R71C223KA01D/Murata GRM1885C1H220JA01D/Murata GRM188R71E152KA01D/Murata GRM188R61C105KA93D/Murata GRM31CR61E106MA12L/Murata GRM32ER60J107ME20L/Murata 7443320100/Wurth Elektronik Optional/Vishay Dale CRCW060310K0FKEA/Vishay Dale CRCW0603121KFKEA/Vishay Dale CRCW060359K0FKEA /Vishay Dale CRCW060320K0FKEA/Vishay Dale CRCW060327K4FKEA/Vishay Dale CRCW06030000Z0EA/Vishay Dale CRCW06036R80FKEA/Vishay Dale ADP2389/Analog Devices, Inc. M20-9990245/Harwin M20-9990346/Harwin 8191/Keystone Electronics UG-863 ADP2389-EVALZ/ADP2390-EVALZ User Guide Table 3. ADP2390 Bill of Materials Qty. 2 2 1 1 1 1 5 5 1 Reference Designator C1, C7 C2, C18 C3 C4 C5 C6 C8, C9, C10, C11, C12 C13, C14, C15, C16, C17 L1 4 2 1 1 1 1 1 1 1 R1, R3, R4, R8 R2, R5 R6 R7 R9 R10 R11 R12 U1 11 J1, J2, J3, J4, J6, J8, J9, J10, J11, J13, J16 1 4 J5 J7, J12, J14, J15 Description 0.1 F, 16 V, capacitor, 0603 Optional, capacitor, 0603 22 nF, 16 V, capacitor, 0603 22 pF, 50 V, capacitor, 0603 1.5 nF, 25 V, capacitor, 0603 1 F, 16 V, capacitor, 0603 10 F, 25 V, capacitor, 1206 100 F, 6.3 V, capacitor, 1210 Inductor, 7443320100, L = 1 H, ISAT = 32 A, DCR = 1.17 m Optional, resistor, 0603 10 k, 1%, resistor, 0603 121 k, 1%, resistor, 0603 59 k, 1%, resistor, 0603 20 k, 1%, resistor, 0603 27.4 k, 1%, resistor, 0603 0 , 0.1 W, resistor, 0603 6.8 , 1%, resistor, 0603 18 V, 12 A, synchronous, step-down regulator, 32-lead, LFCSP_VQ, with exposed paddles Test point, 2.54 mm pitch SIL vertical PC tail pin header, 6.1 mm mating pin height, tin, SIP1 Jumper, 0.1-inch header, 3-way, SIP3 Terminal screw vertical PC mount Part Number/Vendor GRM188R71C104KA01D/Murata Optional/Murata GRM188R71C223KA01D/Murata GRM1885C1H220JA01D/Murata GRM188R71E152KA01D/Murata GRM188R61C105KA93D/Murata GRM31CR61E106MA12L/Murata GRM32ER60J107ME20L/Murata 7443320100/Wurth Elektronik Optional/Vishay Dale CRCW060310K0FKEA/Vishay Dale CRCW0603121KFKEA/Vishay Dale CRCW060359K0FKEA /Vishay Dale CRCW060320K0FKEA/Vishay Dale CRCW060327K4FKEA/Vishay Dale CRCW06030000Z0EA/Vishay Dale CRCW06036R80FKEA/Vishay Dale ADP2390/Analog Devices, Inc. M20-9990245/Harwin M20-9990346/Harwin 8191/Keystone Electronics ESD Caution ESD (electrostatic discharge) sensitive device. Charged devices and circuit boards can discharge without detection. Although this product features patented or proprietary protection circuitry, damage may occur on devices subjected to high energy ESD. Therefore, proper ESD precautions should be taken to avoid performance degradation or loss of functionality. Legal Terms and Conditions By using the evaluation board discussed herein (together with any tools, components documentation or support materials, the "Evaluation Board"), you are agreeing to be bound by the terms and conditions set forth below ("Agreement") unless you have purchased the Evaluation Board, in which case the Analog Devices Standard Terms and Conditions of Sale shall govern. Do not use the Evaluation Board until you have read and agreed to the Agreement. Your use of the Evaluation Board shall signify your acceptance of the Agreement. This Agreement is made by and between you ("Customer") and Analog Devices, Inc. ("ADI"), with its principal place of business at One Technology Way, Norwood, MA 02062, USA. Subject to the terms and conditions of the Agreement, ADI hereby grants to Customer a free, limited, personal, temporary, non-exclusive, non-sublicensable, non-transferable license to use the Evaluation Board FOR EVALUATION PURPOSES ONLY. Customer understands and agrees that the Evaluation Board is provided for the sole and exclusive purpose referenced above, and agrees not to use the Evaluation Board for any other purpose. Furthermore, the license granted is expressly made subject to the following additional limitations: Customer shall not (i) rent, lease, display, sell, transfer, assign, sublicense, or distribute the Evaluation Board; and (ii) permit any Third Party to access the Evaluation Board. As used herein, the term "Third Party" includes any entity other than ADI, Customer, their employees, affiliates and in-house consultants. The Evaluation Board is NOT sold to Customer; all rights not expressly granted herein, including ownership of the Evaluation Board, are reserved by ADI. CONFIDENTIALITY. This Agreement and the Evaluation Board shall all be considered the confidential and proprietary information of ADI. Customer may not disclose or transfer any portion of the Evaluation Board to any other party for any reason. Upon discontinuation of use of the Evaluation Board or termination of this Agreement, Customer agrees to promptly return the Evaluation Board to ADI. ADDITIONAL RESTRICTIONS. Customer may not disassemble, decompile or reverse engineer chips on the Evaluation Board. Customer shall inform ADI of any occurred damages or any modifications or alterations it makes to the Evaluation Board, including but not limited to soldering or any other activity that affects the material content of the Evaluation Board. Modifications to the Evaluation Board must comply with applicable law, including but not limited to the RoHS Directive. TERMINATION. ADI may terminate this Agreement at any time upon giving written notice to Customer. Customer agrees to return to ADI the Evaluation Board at that time. LIMITATION OF LIABILITY. THE EVALUATION BOARD PROVIDED HEREUNDER IS PROVIDED "AS IS" AND ADI MAKES NO WARRANTIES OR REPRESENTATIONS OF ANY KIND WITH RESPECT TO IT. ADI SPECIFICALLY DISCLAIMS ANY REPRESENTATIONS, ENDORSEMENTS, GUARANTEES, OR WARRANTIES, EXPRESS OR IMPLIED, RELATED TO THE EVALUATION BOARD INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, TITLE, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS. IN NO EVENT WILL ADI AND ITS LICENSORS BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES RESULTING FROM CUSTOMER'S POSSESSION OR USE OF THE EVALUATION BOARD, INCLUDING BUT NOT LIMITED TO LOST PROFITS, DELAY COSTS, LABOR COSTS OR LOSS OF GOODWILL. ADI'S TOTAL LIABILITY FROM ANY AND ALL CAUSES SHALL BE LIMITED TO THE AMOUNT OF ONE HUNDRED US DOLLARS ($100.00). EXPORT. Customer agrees that it will not directly or indirectly export the Evaluation Board to another country, and that it will comply with all applicable United States federal laws and regulations relating to exports. GOVERNING LAW. This Agreement shall be governed by and construed in accordance with the substantive laws of the Commonwealth of Massachusetts (excluding conflict of law rules). Any legal action regarding this Agreement will be heard in the state or federal courts having jurisdiction in Suffolk County, Massachusetts, and Customer hereby submits to the personal jurisdiction and venue of such courts. The United Nations Convention on Contracts for the International Sale of Goods shall not apply to this Agreement and is expressly disclaimed. (c)2015 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. UG13375-0-9/15(0) Rev. 0 | Page 8 of 8