19-1462; Rev 0; 6/99 MAX618 Evaluation Kit The MAX618 evaluation kit (EV kit) is a constant-frequency, PWM, step-up switching regulator with an internal 2A, 28V n-channel MOSFET. The EV kit accepts a +3V to VOUT input and converts it to a 12V output for currents up to 500mA. Conversion efficiency is greater than 90%. The EV kit operates at 250kHz, allowing the use of small external components. The MAX618 EV kit is a fully assembled and tested surface-mount circuit board. Features ♦ +3V to VOUT Input Voltage Range ♦ 12V or Adjustable Output Voltage ♦ Up to 500mA Output Current ♦ Internal 2A, 28V MOSFET Switch ♦ 3µA Shutdown Current ♦ 250kHz Switching Frequency ♦ Surface-Mount Components ♦ Fully Assembled and Tested Component List DESIGNATION QTY C1, C2 2 DESCRIPTION 68µF, 20V low-ESR tantalum caps AVX TPSE686M020R0150 or Sprague 593D686X0020E2W Ordering Information PART TEMP. RANGE MAX618EVKIT 0°C to +70°C IC PACKAGE 16 QSOP _________________________Quick Start The MAX618 EV kit is fully assembled and tested. Follow these steps to verify board operation. Do not turn on the power supply until all connections are completed. C3 1 0.1µF ceramic capacitor C4 1 4.7µF, 10V X5R ceramic capacitor Taiyo Yuden LMK316BJ475ML C5 1 0.047µF ceramic capacitor C6, C7 2 1µF, 25V X5R ceramic capacitors Taiyo Yuden TMK316BJ105KL C8 1 68pF ceramic capacitor D1 1 2A Schottky diode SGS-Thomson STPS2L25U, Nihon EC21QS03L, or Central Semiconductor CMSH2-40M L1 1 15µH power inductor Sumida CDRH6D38-150 (shielded), Sumida CR75-150 (unshielded), or Sumida CDH74-150 (unshielded) R1 1 715kΩ ±1% resistor R2 1 100kΩ ±1% resistor U1 1 MAX618EEE JU1 1 3-pin header None 1 Shunt None 1 MAX618 PC board SHUNT LOCATION None 1 MAX618 data sheet 1) Connect a +5V supply to the VIN pad. Connect ground to the GND pad. 2) Connect a voltmeter and load, if any, to the VOUT pad. 3) Place the shunt across JU1 pins 2 and 3. 4) Turn on the power supply to the board and verify that the output voltage is 12V. 5) For other output voltages, refer to the Output Voltage Selection section in the MAX618 data sheet for instructions on selecting feedback resistors R1 and R2, inductor L1, output capacitor C2, and compensation capacitors C5 and C8. Note: Input (C1) and output (C2) capacitors are rated at 20V. Jumper Selection The 3-pin header JU1 selects shutdown mode. Table 1 lists the selectable jumper options in shutdown mode. Table 1. Jumper JU1 Shutdown Function SHDN PIN MAX618 OUTPUT 1&2 Connected to GND Shutdown mode, VOUT = VIN - VDIODE 2&3 Connected to VL MAX618 enabled, VOUT = 12V ________________________________________________________________ Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769. Evaluates: MAX618 General Description Evaluates: MAX618 MAX618 Evaluation Kit VIN C1 68µF 20V C3 0.1µF 10 IN 1 SHDN 5 2 JU1 L1 15µH C7 1µF 25V LX SHDN 3 LX MAX618 11 VL LX PGND VL PGND C4 4.7µF 10V PGND 6 C5 0.047µF COMP FB 2 3 4 D1 VOUT +12V C6 1µF 25V C2 68µF 20V 13 14 15 7 R1 715k 1% GND 1, 8, 9, 12, 16 R2 100k 1% C8 68pF NOTE: HEAVY LINES INDICATE HIGH-CURRENT PATHS. Figure 1. MAX618 EV Kit Schematic 2 _______________________________________________________________________________________ MAX618 Evaluation Kit Evaluates: MAX618 1.0" Figure 2. MAX618 EV Kit—Component Placement Guide 1.0" 1.0" Figure 3. MAX618 EV Kit PC Board Layout—Component Side Figure 4. MAX618 EV Kit PC Board Layout—Solder Side _______________________________________________________________________________________ 3 Evaluates: MAX618 MAX618 Evaluation Kit NOTES 4 _______________________________________________________________________________________ MAX618 Evaluation Kit _______________________________________________________________________________________ Evaluates: MAX618 NOTES 5 Evaluates: MAX618 MAX618 Evaluation Kit NOTES Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 6 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 1999 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.