MAX608 Evaluation Kit ____________________________Features ♦ 5V or Adjustable Output Voltage ♦ 1.8V to VOUT + 0.4V Input Range ♦ Up to 0.5A Output Current ♦ 5µA Max Shutdown Current ♦ 110µA Max Supply Current (MAX608 I.C. only) ♦ Up to 300kHz Switching Frequency ♦ 8-Pin SO, Surface-Mount Construction ____________________Component List DESIGNATION QTY DESCRIPTION C1 1 68µF, 20V tantalum capacitor Sprague 593D686X0020E2W AVX TPSE686M020R0150 C2, C3 2 100µF, 16V tantalum capacitors Sprague 593D107X0016E2W AVX TPSE107M016R0100 C4, C5 2 0.1µF ceramic capacitors Vitramon VT1206Y104KXA D1 1 3A, 40V Schottky diode Nihon NSQ03A04 Motorola MBRU340T3 L1 1 N1 1 R1 1 ♦ Fully Assembled and Tested 22µH inductor Sumida CDRH125-220 N-channel MOSFET (SOT-223) Motorola MMFT3055EL 0.050Ω, 1% resistor (SMT) Dale WSL-2010-R050-F IRC LR2010-01-R050-F U1 1 Maxim MAX608ESA (SO-8) JU1 1 3-pin header None 1 Shunt None 1 Printed circuit board None 1 MAX608 data sheet ______________Ordering Information PART MAX608EVKIT-SO TEMP. RANGE 0°C to +70°C BOARD TYPE Surface Mount ______________Component Suppliers SUPPLIER PHONE FAX AVX (803) 946-0690 (803) 626-3123 Dale (402) 564-3131 (402) 563-6418 IRC (512) 992-7900 (512) 992-3377 Motorola (602) 303-5454 (602) 994-6430 Nihon (805) 867-2555 (805) 867-2698 Sprague (603) 224-1961 (603) 224-1430 Sumida (708) 956-0666 (708) 956-0702 Vishay/Vitramon (203) 268-6261 (203) 452-5670 ________________________________________________________________ Maxim Integrated Products Call toll free 1-800-998-8800 for free samples or literature. 1 Evaluates: MAX608 _______________General Description The MAX608 evaluation kit (EV kit) provides a regulated 5V or adjustable output voltage from an input source as low as 1.8V. It drives loads up to 0.5A with greater than 80% conversion efficiency. This EV kit is a fully assembled and tested surfacemount circuit board. Additional pads on the bottom of the board accommodate the external feedback resistors for setting different output voltages. Evaluates: MAX608 MAX608 Evaluation Kit _________________________Quick Start Table 1. Jumper JU1 Functions The MAX608 EV kit is a fully assembled and tested surface-mount printed circuit board. Follow the steps below to verify board operation. Do not turn on the power supply until all connections are completed. 1) Connect a 3V supply to the pad marked VIN. The ground connects to the GND pad. SHUNT LOCATION SHDN PIN 2&3 Connected to VIN 1&2 Connected to GND MAX608 OUTPUT Shutdown mode, VOUT = VIN - 0.4V MAX608 enabled, VOUT = 5.0V Inductor Selection 2) Connect a voltmeter and load (if any) to the VOUT pad. The 22µH Sumida CDRH125-220 inductor mounted on the EV kit board is a low-resistance, shielded, mediumcurrent inductor. It provides excellent performance over the line and load ranges. Refer to the section Determining the Inductor in the MAX608 data sheet for instructions on selecting the inductor value. 3) Place the shunt on JU1 across pins 1 and 2 for normal operation. 4) Turn on the power and verify that the output voltage is 5V. 5) Refer to the section Evaluating Other Output Voltages to modify the board for different output voltages. Evaluating Other Output Voltages The MAX608 is preset for a 5V output voltage. However, its output may also be adjusted via an external voltage divider formed by R2 and R3 (located on the bottom side of the board). The only other modification required is to cut the trace across R3. The section Setting the Output Voltage in the MAX608 data sheet gives instructions for calculating R2 and R3 values. For output voltages greater than 15V, use the MAX1771. _______________Detailed Description Jumper Selection The 3-pin header JU1 selects shutdown mode. Table 1 lists the selectable jumper options. VIN C1 68µF 20V L1 22µH D1 NSQ03A03 VOUT SHDN C2 100µF 16V 3 4 2 JU1 1 5 GND SHDN REF U1 EXT MAX608 CS+ 1 8 N1 MMFT3055ELT1 3 GND 7 FB GND OUT AGND 2 6 R2 OPEN GND C5 0.1µF Figure 1. MAX608 EV Kit Schematic 2 C6 OPEN R1 0.050Ω C4 0.1µF C3 100µF 16V _______________________________________________________________________________________ R3 0Ω MAX608 Evaluation Kit Evaluates: MAX608 Figure 2. MAX608 EV Kit Component Placement Guide— Component Side Figure 3. MAX608 EV Kit Component Placement Guide— Solder Side Figure 4. MAX608 EV Kit PC Board Layout— Component Side Figure 5. MAX608 EV Kit PC Board Layout— Solder Side _______________________________________________________________________________________ 3 Evaluates: MAX608 MAX608 Evaluation Kit 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. 4 ___________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © 1995 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.