MAX17504EVKITB#

Evaluates: MAX17504 in 5V Output-Voltage Application MAX17504 5V Output Evaluation Kit General Description The MAX17504 5V output evaluation kit (EV kit) provides a proven design to evaluate the MAX17504 high-voltage, high-efficiency, synchronous step-down DC-DC converter. The EV kit is preset for 5V output at load currents up to 3.5A and features a 500kHz switching frequency for optimum efficiency and component size. The EV kit features adjustable input undervoltage lockout, adjustable soft-start, open-drain RESET signal, and external frequency synchronization. Ordering Information appears at end of data sheet. Features ●● Operates from a 7.5V to 60V Input Supply ●● 5V Output Voltage ●● Up to 3.5A Output Current ●● 500kHz Switching Frequency ●● E nable/UVLO Input, Resistor-Programmable UVLO Threshold ●● Adjustable Soft-Start Time ●● M ODE Pin to Select Among PWM, PFM, or DCM Modes ●● Open-Drain RESET Output ●● External Frequency Synchronization ●● Overcurrent and Overtemperature Protection ●● Proven PCB Layout ●● Fully Assembled and Tested Component List DESIGNATION QTY L1 1 10µH, 5.5A inductor TDK SLF12575T-100M5R4-H Taiyo Yuden NS10165T100MNA 2.2µF ±10%, 10V X7R ceramic capacitor (0603) Murata GRM188R71A225K R1 1 3.32MΩ ±1% resistor (0402) R2 1 604kΩ ±1% resistor (0402) R3 1 100kΩ ±1% resistor (0402) 12000pF ±10%, 16V X7R ceramic capacitor (0402) Murata GRM155R71C123K R4 1 22.1kΩ ±1% resistor (0402) R5 0 Not installed, resistor (0402) R6 1 10kΩ ±1% resistor (0402) TP1, TP2 2 Test pads U1 1 Buck converter (20 TQFN-EP*) Maxim MAX17504ATP+ — 3 Shunts (JU1–JU3) — 1 PCB: MAX17504 – 5V Output EVKIT DESIGNATION QTY C1, C8 2 2.2µF ±10%, 100V X7R ceramic capacitors (1210) Murata GRM32ER72A225KA35 1 C2 C3 1 DESCRIPTION C4, C9 2 22µF ±10%, 10V X7R ceramic capacitors (1210) Murata GRM32ER71A226K C5 1 0.1µF ±10%, 16V X7R ceramic capacitor (0402) Murata GRM155R71C104K C6 0 Not installed, ceramic capacitor (0402) C7 1 47µF, 80V aluminum electrolytic capacitor (D = 10mm) Panasonic EEEFK1K470P JU1–JU3 3 3-pin headers 19-6889; Rev 1; 2/14 DESCRIPTION *EP = Exposed pad. Note: C7, R1, and R2 are optional components; R1 and R2 are not needed if the EN/UVLO pin is permanently connected to VIN. The electrolytic capacitor (C7) is required only when the VIN power supply is situated far from the MAX17504-based circuit. When R5 is open, the device switches at 500kHz switching frequency. The SLF12575 inductor has been used to prepare the EV kit test report. MAX17504 5V Output Evaluation Kit Evaluates: MAX17504 in 5V Output-Voltage Application Component Suppliers SUPPLIER PHONE WEBSITE Murata Americas 800-241-6574 www.murataamericas.com Panasonic Corp. 800-344-2112 www.panasonic.com Taiyo Yuden 800-348-2496 www.t-yuden.com TDK Corporation 847-699-2299 www.tdk.com Note: Indicate that you are using the MAX17504 when contacting these component suppliers. Quick Start Recommended Equipment ●● MAX17504 5V output EV kit ●● 7.5V to 60V, 7A DC input power supply ●● Load capable of sinking 3.5A ●● Digital voltmeter (DVM) Procedure The EV kit is fully assembled and tested. Follow the steps below to verify the board operation. Caution: Do not turn on power supply until all connections are completed. 1) Set the power supply at a voltage between 7.5V and 60V. Disable the power supply. 2) Connect the positive terminal of the power supply to the VIN PCB pad and the negative terminal to the nearest PGND PCB pad. Connect the positive terminal of the 3.5A load to the VOUT PCB pad and the negative terminal to the nearest PGND PCB pad. 3) Connect the DVM across the VOUT PCB pad and the nearest PGND PCB pad. 4) Verify that shunts are installed across pins 1-2 on jumper JU1 and pins 2-3 on jumper JU3 (see Tables 1 and 3 for details). 5) Select the shunt position on jumper JU2 according to the intended mode of operation (see Table 2 for details). 6) Turn on the DC power supply. Detailed Description The MAX17504 5V output EV kit provides a proven design to evaluate the MAX17504 high-voltage, highefficiency, synchronous step-down DC-DC converter. The EV kit is preset for 5V output from 7.5V to 60V input at load currents up to 3.5A and features a 500kHz switching frequency for optimum efficiency and component size. The EV kit includes an EN/UVLO PCB pad and jumper JU1 to enable the output at a desired input voltage. The SYNC PCB pad and jumper JU3 allow an external clock to synchronize the device. Jumper JU2 allows the selection of a particular mode of operation based on light-load performance requirements. An additional RESET PCB pad is available for monitoring whether the converter output is in regulation. Soft-Start Input (SS) The device utilizes an adjustable soft-start function to limit inrush current during startup. The soft-start time is adjusted by the value of C3, the external capacitor from SS to GND. The selected output capacitance (CSEL) and the output voltage (VOUT) determine the minimum value of C3, as shown by the following equation: C3 ≥ 28 x 10-6 x CSEL x VOUT The soft-start time (tSS) is related to C3 by the following equation: tSS = C3/(5.55 x 10-6) For example, to program a 2.2mS soft-start time, C3 should be 12nF. 7) Enable the load. 8) Verify that the DVM displays 5V. www.maximintegrated.com Maxim Integrated │  2 Evaluates: MAX17504 in 5V Output-Voltage Application MAX17504 5V Output Evaluation Kit Regulator Enable/Undervoltage-Lockout Level (EN/UVLO) The device offers an adjustable input undervoltagelockout level. For normal operation, a shunt should be installed across pins 1-2 on jumper JU1. To disable the output, install a shunt across pins 2-3 on JU1 and the EN/ UVLO pin is pulled to GND. See Table 1 for JU1 settings. Set the voltage at which the device turns on with the resistive voltage-divider R1/R2 connected from VIN_ to SGND. Connect the center node of the divider to EN/UVLO. Choose R1 to be 3.32MΩ and then calculate R2 as follows: R1× 1.215 R2 = (VINU − 1.215) where VINU is the voltage at which the device is required to turn on. MODE Selection (MODE) The device’s MODE pin can be used to select among PWM, PFM, or DCM modes of operation. The logic state of the MODE pin is latched when VCC and EN/UVLO voltages exceed the respective UVLO rising thresholds and all internal voltages are ready to allow LX switching. State changes on the MODE pin are ignored during normal operation. Refer to the MAX17504 IC data sheet for more information on PWM, PFM, and DCM modes of operation. Table 2 shows EV kit jumper settings that can be used to configure the desired mode of operation. Table 1. Regulator Enable (EN/UVLO) Description (JU1) SHUNT POSITION EN/UVLO PIN MAX17504_ OUTPUT 1-2* Connected to VIN Enabled Not installed Connected to the center node of resistor-divider R1 and R2 Enabled, UVLO level set through the R1 and R2 resistors 2-3 Connected to SGND Disabled www.maximintegrated.com External Clock Synchronization (SYNC) The internal oscillator of the device can be synchronized to an external clock signal on the SYNC pin. The external synchronization clock frequency must be between 1.1fSW and 1.4fSW, where fSW is the frequency of operation set by R5. The minimum external clock high pulse width should be greater than 50ns and the minimum external clock low pulse width should be greater than 160ns. Table 2. MODE Description (JU2) SHUNT POSITION MODE PIN MAX17504_ MODE Not installed* Unconnected PFM mode of operation 1-2 Connected to SGND PWM mode of operation 2-3 Connected to VCC DCM mode of operation Table 3. SYNC Description (JU3) SHUNT POSITION SYNC PIN MAX17504_ SYNC 1-2 Connected to test loop on PCB Frequency can be synchronized with an external clock 2-3* Connected to SGND SYNC feature unused Maxim Integrated │  3 Evaluates: MAX17504 in 5V Output-Voltage Application MAX17504 5V Output Evaluation Kit EV Kit Test Report 5V OUTPUT, PWM MODE EFFICIENCY VS. LOAD CURRENT 5V OUTPUT, PWM MODE LOAD AND LINE REGULATION 5.08 figure 1 5.07 90 5.05 VIN = 36V EFFICIENCY (%) OUTPUT VOLTAGE (V) 5.06 5.04 5.03 5.02 5.01 MODE = SGND 500 1000 VIN = 24V 70 1500 2000 2500 3000 40 3500 VIN = 12V MODE = SGND 0 5V OUTPUT, PFM MODE EFFICIENCY VS. LOAD CURRENT figure 2 5.2 EFFICIENCY (%) OUTPUT VOLTAGE (V) 90 VIN = 24V 5.1 5.0 4.9 VIN = 12V 4.5 500 70 VIN = 48V VIN = 24V VIN = 36V 60 VIN = 12V 40 MODE = OPEN 0 80 50 VIN = 48V VIN = 36V 4.6 figure 4 100 5.4 4.7 1000 1500 2000 2500 3000 3500 Figure 3. MAX17504 5V Output Efficiency (PWM Mode) 5V OUTPUT, PFM MODE LOAD AND LINE REGULATION 4.8 500 LOAD CURRENT (mA) Figure 1. MAX17504 5V Output Load and Line Regulation (PWM Mode) 5.3 VIN = 48V 60 LOAD CURRENT (mA) 5.5 VIN = 36V 50 4.99 0 80 VIN = 24V VIN = 12V VIN = 48V 5.00 4.98 figure 3 100 1000 1500 2000 2500 3000 3500 LOAD CURRENT (mA) Figure 2. MAX17504 5V Output Load and Line Regulation (PFM Mode) www.maximintegrated.com 30 MODE = OPEN 1 10 100 1000 3500 LOAD CURRENT (mA) Figure 4. MAX17504 5V Output Efficiency (PFM Mode) Maxim Integrated │  4 Evaluates: MAX17504 in 5V Output-Voltage Application MAX17504 5V Output Evaluation Kit EV Kit Test Report (continued) 5V OUTPUT, DCM MODE EFFICIENCY VS. LOAD CURRENT 100 VIN = 48V EFFICIENCY (%) 90 VI N= 36V 80 VIN = 24V 70 60 VIN = 12V 50 40 30 MODE = VCC 1 10 100 1000 3500 LOAD CURRENT (mA) Figure 5. MAX17504 5V Output Efficiency (DCM Mode) Figure 6. MAX17504 5V Output Full Load Bode Plot (VIN = 24V) 5V OUTPUT, PWM MODE (LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A) figure 7 100mV/div VOUT (AC) IOUT MODE = SGND 1A/div 40μs/div Figure 7. MAX17504 5V Output, No Load to 1.75A Load Transient (PWM Mode) www.maximintegrated.com Maxim Integrated │  5 Evaluates: MAX17504 in 5V Output-Voltage Application MAX17504 5V Output Evaluation Kit EV Kit Test Report (continued) 5V OUTPUT, DCM MODE (LOAD CURRENT STEPPED FROM 50mA TO 1.75A) 5V OUTPUT, PFM MODE (LOAD CURRENT STEPPED FROM 5mA TO 1.75A) figure 8 figure 9 VOUT (AC) IOUT 100mV/div 100mV/div VOUT (AC) 1A/div 1A/div IOUT MODE = OPEN MODE = VCC 2ms/div 200μs/div Figure 8. MAX17504 5V Output, 5mA to 1.75A Load Transient (PFM Mode) Figure 9. MAX17504 5V Output, 50mA to 1.75A Load Transient (DCM Mode) 5V OUTPUT, PWM MODE (LOAD CURRENT STEPPED FROM 1.75A TO 3.5A) figure 10 VOUT (AC) 100mV/div 2A/div IOUT 40μs/div Figure 10. MAX17504 5V Output, 1.75A to 3.5A Load Transient www.maximintegrated.com Maxim Integrated │  6 MAX17504 5V Output Evaluation Kit Evaluates: MAX17504 in 5V Output-Voltage Application Figure 11. MAX17504 5V Output EV Kit Schematic www.maximintegrated.com Maxim Integrated │  7 MAX17504 5V Output Evaluation Kit Evaluates: MAX17504 in 5V Output-Voltage Application Figure 12. MAX17504 5V Output EV Kit Component Placement Guide—Component Side Figure 14. MAX17504 5V Output EV Kit PCB Layout— Inner Layer 1 Figure 13. MAX17504 5V Output EV Kit Component Side PCB layout Figure 15. MAX17504 5V Output EV Kit PCB Layout—Inner Layer 2 www.maximintegrated.com Maxim Integrated │  8 MAX17504 5V Output Evaluation Kit Figure 16. MAX17504 5V Output EV Kit PCB Layout— Solder Side Evaluates: MAX17504 in 5V Output-Voltage Application Figure 17. MAX17504 5V Output EV Kit Component Placement Guide—Top Solder Mask Figure 18. MAX17504 5V Output EV Kit Component Placement Guide—Bottom Solder Mask www.maximintegrated.com Maxim Integrated │  9 MAX17504 5V Output Evaluation Kit Evaluates: MAX17504 in 5V Output-Voltage Application Ordering Information PART TYPE MAX17504EVKITB# EV Kit #Denotes RoHS compliant. www.maximintegrated.com Maxim Integrated │  10 Evaluates: MAX17504 in 5V Output-Voltage Application MAX17504 5V Output Evaluation Kit Revision History REVISION NUMBER REVISION DATE 0 12/13 Initial release — 1 2/14 Fixed typo in Figure 6 5 DESCRIPTION PAGES CHANGED For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. © 2014 Maxim Integrated Products, Inc. │  11