19-2774; Rev 0; 2/03 MAX1910 Evaluation Kit Features ♦ Current-Regulated Charge Pump ♦ 60mA Output Current ♦ No Inductor Required ♦ 750kHz Operation Minimizes Input Ripple ♦ Uses Small Ceramic Capacitors Component List DESIGNATION QTY DESCRIPTION C1, C2 2 0.47µF ±10%, 10V X5R ceramic capacitors (0603) Taiyo Yuden LMK107BJ474KA C3, C4 2 2.2µF ±10%, 10V X5R ceramic capacitors (0805) Taiyo Yuden LMK212BJ225KG R1–R4 4 R6 0 15Ω ±5% resistors (0805) Not installed (0805) PC board shorts Not installed (0805) R11 1 1Ω ±5% resistor (0805) R13 1 100kΩ ±5% resistor (0805) 4 White LEDs (surface mount 3mm x 2mm) Kingbright AA3020PWC, Nichia: NSCW455, or Nichia: NSCW215T R5, R7 0 ♦ Load Disconnected in Shutdown ♦ 1µA Shutdown Current ♦ Small 10-Pin µMAX Package ♦ Fully Assembled and Tested Ordering Information PART MAX1910EVKIT TEMP RANGE IC PACKAGE -40°C to +85°C 10 µMAX Quick Start JU1 1 3-pin header U1 1 MAX1910EUB (10-pin µMAX) The MAX1910 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: 1) Preset the power supply to between 2.7V and 4.2V. None 1 Shunt 2) Verify shunt JU1 is on pins 1 and 2 (enable). None 1 MAX1910 EV kit PC board 3) Connect the positive (+) lead of the power supply to the IN1 pad. D1–D4 4) Connect the negative (-) lead of the power supply to the GND pad. Component Suppliers SUPPLIER PHONE WEBSITE Kamaya 260-489-1533 www.kamaya.com Kingbright 888-546-4533 www.kingbright.com Nichia 248-352-6575 www.nichia.com Taiyo Yuden 408-573-4150 www.t-yuden.com 5) Turn on the power supply. 6) Verify that the LEDs are lit. 7) Vary the power supply from 2.7V to 4.2V. 8) To verify shutdown mode, move shunt JU1 to pins 2 and 3. The LEDs turn off. 9) Move shunt JU1 back to pins 1 and 2. The LEDs turn back on. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 Evaluates: MAX1910/MAX1912 General Description The MAX1910 evaluation (EV) kit is a fully assembled and tested circuit board containing a complete circuit driving four parallel white LEDs. The circuit operates from a 2.7V to 5.3V input supply. A MAX1910 comes installed on the board, but the EV kit can also be used to evaluate the MAX1912. Evaluates: MAX1910/MAX1912 MAX1910 Evaluation Kit 1) Cut the PC board traces that short the pads for R5 and R7. Detailed Description Jumper Selection 2) Short the pads of R6. Shutdown Mode The MAX1910 features a shutdown mode that reduces input current to 0.1µA (typ). Place the shunt across pins 1 and 2 of JU1 for normal operation. Place the shunt across pins 2 and 3 of JU1 for shutdown mode (Table 1). 3) R5 remains open. 4) Install a resistor in R7. R7 sets the sum of all LED currents, and its value is found from: R7 = 0.2 IL Table 1. Jumper JU1 Functions SHUNT LOCATION SHDN PIN Connecting an External Load OUTPUT 1 and 2 Connected to IN Enabled 2 and 3 Connected to GND Shutdown To use an external load in place of the four LEDs (such as an LED module), first follow the steps listed in the Regulating the Total Current Through LEDs section. Next, remove the four LEDs (D1–D4), or the four ballast resistors (R1–R4). An external load can now be connected from OUT1+ to OUT1-. The current through the external load is regulated to the current set by R7. Regulating the Total Current Through LEDs In the default configuration, the current through LED D4 is set by the resistor R4. The current through the other LEDs tracks the current in the regulated LED. Refer to the MAX1910/MAX1912 data sheet for other LED matching and ballasting configurations. Evaluating the MAX1912 To evaluate the MAX1912, carefully remove U1 from the PC board and replace it with the MAX1912. Free samples of the MAX1912 can be obtained from Maxim. The EV kit can also be configured to regulate the total current through the LEDs by following these steps: 1 JU1 R13 100kΩ 2 3 IN R11 1Ω C3 2.2µF GND 6 8 2 4 C1 0.47µF 9 7 C2 0.47µF 3 IN1 IN2 C1+ C1- SHDN OUT U1 OUT1+ 5 R5 SHORT MAX1910 D4 D3 D2 D1 C2+ SET C2GND 1 10 R6 OPEN R4 15Ω R3 15Ω R2 15Ω R1 15Ω R7 SHORT Figure 1. MAX1910 EV Kit Schematic 2 C4 2.2µF _______________________________________________________________________________________ OUT1- MAX1910 Evaluation Kit Figure 3. MAX1910 EV Kit PC Board Layout—Component Side Figure 4. MAX1910 EV Kit PC Board Layout—Solder Side 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 3 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. Evaluates: MAX1910/MAX1912 Figure 2. MAX1910 EV Kit Component Placement Guide— Component Side