19-2894; Rev 1; 4/04 MAX1573 Evaluation Kit The MAX1573 evaluation kit (EV kit) is a fully assembled and tested surface-mount circuit board. The EV kit contains the MAX1573, a white LED driver with a high-efficiency charge pump. The EV kit accepts a 2.7V to 5.5V input voltage and drives up to 4 white LEDs with regulated constant current for uniform intensity. The MAX1573 runs at 1MHz fixed frequency, allowing tiny external components. An EV kit is available for both the UCSP and the TQFN packages. Component List DESIGNATION QTY DESCRIPTION C1–C4 4 1µF ±10%, 6.3V X5R ceramic capacitors (0603) TDK C1608X5R0J105K D1–D4 4 Surface-mount white LEDs Nichia NSCW215T JU1, JU2 2 3-pin headers Features ♦ Proprietary Adaptive 1x/1.5x Modes ♦ High Efficiency (PLEDs / PBATT), Up to 92% ♦ 2% LED Current Matching ♦ 28mA/LED Drive Capability ♦ Eliminates Ballast Resistor ♦ Low 0.1µA Shutdown Current ♦ 2.7V to 5.5V Input Voltage Range ♦ Tiny 2.1 x 2.1 x 0.6mm UCSP Package ♦ Surface-Mount Components ♦ Fully Assembled and Tested Ordering Information PART TEMP RANGE IC PACKAGE JU3 1 Not installed R1 1 7.5kΩ ±1% resistor (0603) MAX1573EVKIT 0°C to +70°C 14 UCSP 4 x 4 U1 1 MAX1573EBE or MAX1573ETE MAX1573TQFNEVKIT 0°C to +70°C 16 TQFN None 2 Shunts None 1 MAX1573EVKIT PC board Component Suppliers SUPPLIER Nichia COMPONENT PHONE WEBSITE LEDs 717-285-2323 www.nichia.com Resistors 714-373-7366 www.maco.panasonic.co.jp Taiyo Yuden Capacitors 408-573-4150 www.t-yuden.com TDK Capacitors 888-835-6646 www.component.tdk.com Panasonic Note: Please indicate that you are using the MAX1573 when contacting these suppliers. Quick Start Recommended Equipment For evaluation of either EV kit: • Variable-output power supply capable of supplying up to +5.5V at 300mA Procedure The MAX1573 EV kit is fully assembled and tested. Perform the following steps to verify board operation. Do not turn on the power supply until all connections are completed: 1) Verify that shunts are across pins 1 and 2 of JU1 (EN1) and JU2 (EN2). 2) Preset the power supply to 2.7V and turn off. 3) Connect the positive lead of the power supply to the VIN pad on the EV kit board. Connect the ground lead of the power supply to the GND pad directly below the VIN pad. 4) Turn on the power supply. 5) Verify that all 4 white LEDs are on with uniform intensity. UCSP is a trademark of Maxim Integrated Products, Inc. ________________________________________________________________ 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: MAX1573 General Description Evaluates: MAX1573 MAX1573 Evaluation Kit Table 1. JU1 and JU2 Functions (Dimming Control) JU1 POSITION EN1 JU2 POSITION EN2 MAX1573 OUTPUT 1 and 2 Connected to VIN 1 and 2 Connected to VIN Full brightness 1 and 2 Connected to VIN 2 and 3 Connected to GND 3/10 brightness 2 and 3 Connected to GND 1 and 2 Connected to VIN 1/10 brightness 2 and 3 Connected to GND 2 and 3 Connected to GND Shutdown 6) Sweep the power supply to 5.5V. Verify that all 4 LEDs remain on with constant and uniform intensity. across pins 1 and 2 on JU1 and JU2). To set a different LED current, change R1, where R1 = 215 x 0.6 / ILED(FULL). 7) Reconfigure JU1 and JU2 to verify the different brightness levels. For instructions on brightness control, see Table 1. Evaluating Off-Board LEDs The MAX1573 EV kit allows for easy evaluation of offboard LEDs. To evaluate off-board LEDs, first cut the trace that shorts JU3. Next, connect the pad labeled VOUT on the EV kit to the anodes of the LEDs under evaluation. Last, connect the cathode of each LED to one of the EV kit pads labeled LED1–LED4. If evaluating fewer than 4 off-board LEDs, see the Evaluating Fewer Than 4 LEDs section. Detailed Description Jumper Selection EN1 and EN2 on the MAX1573 provide control for ON/OFF, 1/10, 3/10, and full current. JU1 and JU2 connect these 2 pins to either VIN or GND (see Table 1). An external signal can be used to drive EN1 or EN2 by removing the corresponding shunt completely from the jumper and connecting the external signal to the appropriate connecting pad. Evaluating Fewer than 4 LEDs To evaluate fewer than 4 LEDs, remove the desired LED(s) and connect the corresponding LED pad(s) to the input voltage. Do not leave LED pad(s) floating. Setting LED Current The default LED current is set to 17mA (with shunts C2 1µF C3 1µF VOUT D1 C1N VIN 2.7V TO 5.5V C1 A1 B1 C1P C2N B2 C2P OUT IN C4 1µF C1 1µF EN1/PWM 1 2 3 JU1 1 2 3 D1 D2 D3 D4 U1 A3 EN1 MAX1573 LED1 EN2 JU3 SHORT A2 JU2 LED2 A4 EN2 LED3 B4 GND R1 7.5kΩ 1% LED4 SET D4 C4 D3 C3 GND D2 Figure 1. MAX1573 EV Kit Schematic 2 _______________________________________________________________________________________ LED1 LED2 LED3 LED4 GND0 MAX1573 Evaluation Kit Evaluates: MAX1573 Figure 2. MAX1573 UCSP EV Kit Component Placement Guide—Top Silkscreen Figure 4. MAX1573 UCSP EV Kit PC Board Layout— Component Side Figure 3. MAX1573 UCSP EV Kit Component Placement Guide—Bottom Silkscreen Figure 5. MAX1573 UCSP EV Kit PC Board Layout—Solder Side _______________________________________________________________________________________ 3 Evaluates: MAX1573 MAX1573 Evaluation Kit Figure 6. MAX1573 TQFN EV Kit Component Placement Guide—Top Silkscreen Figure 7. MAX1573 TQFN EV Kit Component Placement Guide—Bottom Silkscreen Figure 8. MAX1573 TQFN EV Kit PC Board Layout— Component Side Figure 9. MAX1573 TQFN 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. 4 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.