MAX8506EVKIT

19-3228; Rev 0; 2/04 MAX8506 Evaluation Kit The MAX8506 evaluation kit (EV kit) is a fully assembled and tested surface-mount circuit board that demonstrates the MAX8506 1MHz pulse-width-modulated (PWM) step-down DC-DC converter optimized for powering the power amplifier (PA) in wireless applications. The EV kit can dynamically control the output voltage in the 0.4V to VIN range from a 2.6V to 5.5V input. It can deliver 600mA of load current. The MAX8506 EV kit can also be used to evaluate the MAX8507, which has a different gain, and the MAX8508, whose output can be externally programmed for fixed 0.75V to 3.4V. Features ♦ 2.6V to 5.5V Input Voltage Range ♦ 1MHz Fixed-Frequency PWM Switching ♦ 600mA Output Current ♦ Adjustable Output Voltages 1.76 x REFIN (MAX8506) 2 x REFIN (MAX8507) Set by External Feedback Resistors (MAX8508) ♦ Low 0.1µA (typ) Quiescent Current in Shutdown Mode ♦ Surface-Mount Construction ♦ Fully Assembled and Tested Ordering Information PART TEMP RANGE MAX8506EVKIT 0°C to +70°C IC PACKAGE 16 Thin QFN (4mm x 4mm) Note: To evaluate the other devices, MAX8507/MAX8508, order a MAX8507ETE/MAX8508ETE free sample with the MAX8506EVKIT. Component List DESIGNATION QTY DESCRIPTION C1 1 2.2µF ±10%, 6.3V X5R ceramic capacitor (0603) Taiyo Yuden JMK107BJ225K TDK C1608X5R0J225K C2 1 4.7µF ±10%, 6.3V X5R ceramic capacitor (0603) TDK C1608X5R0J475K 1 0.22µF ±20%, 16V X5R ceramic capacitor (0603) Taiyo Yuden EMK107BJ224MA TDK C1608X7R1C224M 1 1500pF ±10%, 50V X7R ceramic capacitor (0603) Murata GRM188R71H152K TDK C1608X7R1H152K C3 C4 C5 1 0.1µF ±10%, 10V X5R ceramic capacitor (0402) Taiyo Yuden LMK105BJ104KV TDK C1005X5R1A104K DESIGNATION QTY DESCRIPTION C6 1 100pF ±5%, 50V C0G ceramic capacitor (0402) Murata GRP1555C1H101J TDK C1005C0G1H101J L1 1 4.7µH inductor Sumida CDRH2D18/HP-4R7NC TOKO1001AS-4R7M R1 1 10kΩ ±5% resistor (0603) R2 0 Not installed, resistor (0402) U1 1 MAX8506ETE (16-pin thin QFN 4mm x 4mm) JU1, JU2, JU3 3 3-pin headers None 3 Shunts None 1 MAX8506 PC board ________________________________________________________________ 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: MAX8506/MAX8507/MAX8508 General Description Evaluates: MAX8506/MAX8507/MAX8508 MAX8506 Evaluation Kit Component Suppliers SUPPLIER Murata PHONE FAX 770-436-1300 770-436-3030 WEBSITE www.murata.com Sumida 847-545-6700 847-545-6720 www.sumida.com Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com TDK 847-803-6100 847-390-4405 www.component.tdk.com TOKO 847-297-0070 847-699-1194 www.tokoam.com Note: Please indicate that you are using the MAX8506/MAX8507/MAX8508 when contacting these component suppliers. Quick Start The MAX8506 EV kit is a fully assembled and tested surface-mount board. Follow the steps below for board operation. Do not turn on the power supply until all connections are completed: 1) Verify that a shunt is connected across pins 1 and 2 of jumper JU1 (output enabled). 2) Verify that a shunt is connected across pins 2 and 3 of jumper JU2 (high-power bypass mode disabled). 3) Verify that a shunt is connected across pins 1 and 2 of jumper JU3 (PWM mode enabled). 4) Connect a voltmeter across the VOUT and the GND pads to monitor the output voltage. 5) Connect a 2.6V to 5.5V power supply to the VIN pad. Connect the power-supply ground terminal to the GND pad. 6) Connect a 1V power supply to the REFIN pad. Connect the power-supply ground terminal to the GND pad. 7) Turn on the power supplies and verify that the output voltage is 1.76V. Detailed Description The MAX8506 EV kit circuit board demonstrates the MAX8506 1MHz, PWM, step-down DC-DC converter circuit that is optimized to power the PA in wireless applications. The EV kit requires a power supply in the 2.6V to 5.5V range, and has an output voltage dynamically controlled by REFIN. The EV kit board features jumpers that enable the user to configure the shutdown, SKIP/PWM, and high-power (HP) bypass modes. Shutdown Mode The EV kit contains jumper JU1 to allow the user to switch the MAX8506 converter from enable to shutdown mode. Shutdown mode reduces the supply current to 0.1µA (typ) and sets the output voltage to 0V. See Table 1 for JU1 configurations. High-Power Bypass Mode Jumper JU2 allows the user to enable or disable the high-power bypass mode of the MAX8506 converter. When the high-power mode is enabled, the converter stops regulating the output voltage and the output voltage, VOUT, is equal to the input voltage, VIN. When the high-power mode is disabled, the converter regulates the output voltage to the programmed voltage. See Table 2 for JU2 configuration. Removing the shunt on jumper JU2 and applying a CMOS logic-level signal to the HP pad on the EV kit board can also control the high-power bypass mode. Skip/PWM Mode Installing a shunt across pins 2 and 3 of jumper JU3 enables skip-mode operation. This allows automatic PWM control at medium and heavy current loads, and skip mode at light current loads to improve efficiency and reduce quiescent current. Installing a shunt across pins 1 and 2 of JU3 enables forced-PWM operation. Forced-PWM operation is desirable in sensitive RF and data-acquisition applications to ensure that switching harmonics do not interfere with sensitive IF and data- Table 1. Jumper JU1 (SHDN) SHUNT LOCATION MAX8506 OUTPUT Pins 1 and 2 Connected to VIN Output enabled, VOUT = 1.76 x REFIN Pins 2 and 3 Connected to GND Shutdown, VOUT = 0V Connected to SHDN pad Output controlled by the user (user-supplied control signal must be connected to SHDN pad) None 2 SHDN PIN _______________________________________________________________________________________ MAX8506 Evaluation Kit SHUNT LOCATION HP PIN EV KIT OPERATION Pins 1 and 2 Connected to VIN High-power bypass mode enabled, VOUT = VIN Pins 2 and 3 Connected to GND High-power bypass mode disabled Connected to HP pad Output controlled by the user (user-supplied control signal must be connected to HP pad) None Table 3. Jumper JU3 (SKIP) SHUNT LOCATION SKIP PIN OPERATION MODE Pins 1 and 2 Connected to VIN PWM mode at all loads Pins 2 and 3 Connected to GND SKIP mode at light loads and PWM mode at medium and heavy loads Connected to SKIP pad Operation mode controlled by the user (user-supplied control signal must be connected to SKIP pad) None sampling frequencies. Forced-PWM operation uses higher supply current with no load compared to skip mode. See Table 3 for JU3 configuration. Evaluating the MAX8507/MAX8508 The MAX8506 EV kit circuit board comes with the MAX8506 converter installed. The MAX8506 EV kit board can also be used to evaluate the MAX8507/ MAX8508 converters. To evaluate the MAX8507 with the MAX8506 EV kit, replace the MAX8506ETE with the MAX8507ETE, and change R1 to 15kΩ and C4 to 1000pF. To evaluate the MAX8508 with the MAX8506 EV kit, replace the MAX8506ETE with the MAX8508ETE, remove C5, and then install feedback resistors on R2 and C5 pads. Change R1 to 5.62kΩ and C4 to 2700pF. The output voltage, VOUT, can be adjusted in the 0.75V to 3.4V range. Select a feedback resistor, RFeedback, between 5kΩ and 50kΩ and install on the C5 pads. R2 is determined by the following equation: R2 = RFeedback (VOUT / VFB – 1) where VFB = 0.75V and VOUT is the desired output voltage. Care should be taken when soldering or desoldering the exposed paddle under the IC. _______________________________________________________________________________________ 3 Evaluates: MAX8506/MAX8507/MAX8508 Table 2. Jumper JU2 (HP) Evaluates: MAX8506/MAX8507/MAX8508 MAX8506 Evaluation Kit VIN VIN 10 11 C1 2.2µF 6.3V 13 15 GND 8 7 VIN SHDN 1 JU1 1 VIN 3 9 BATT L1 4.7µH BATT BATT PGND N.C. OUT U1 OUT VOUT 12 14 R2 OPEN 3 2 REFIN 2 6 C5 0.1µF GND 16 3 C3 0.22µF COMP GND 2 SKIP REF GND REFIN 4 HP JU2 JU3 C2 4.7µF 6.3V SHDN VIN 1 HP 1 LX MAX8506 2 3 SKIP BATTP R1 10kΩ 5 C6 100pF C4 1500pF Figure 1. MAX8506 EV Kit Schematic 4 _______________________________________________________________________________________ MAX8506 Evaluation Kit Figure 3. MAX8506 EV Kit PC Board Layout—Component Side Figure 4. MAX8506 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 _____________________ 5 © 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. Evaluates: MAX8506/MAX8507/MAX8508 Figure 2. MAX8506 EV Kit Component Placement Guide— Component Side