19-1463; Rev 2; 10/00 MAX2235 Evaluation Kit The MAX2235 evaluation kit (EV kit) simplifies evaluation of the MAX2235 power amplifier (PA). It enables testing of the device’s RF performance and requires no additional support circuitry. The EV kit’s signal inputs and outputs use SMA connectors to facilitate the connection of RF test equipment. The MAX2235 EV kit is assembled with a MAX2235 and incorporates input and output matching components optimized for the 824MHz to 849MHz RF frequency band. All matching components may be changed to work at RF frequencies from 800MHz to 1000MHz. ♦ Easy Evaluation of MAX2235 ♦ +2.7V to +5.5V Single-Supply Operation ♦ RF Input and Output Matched for Operation from 824MHz to 849MHz ♦ All Critical Peripheral Components Included Ordering Information Component Suppliers SUPPLIER PHONE FAX ATC 516-622-4700 516-622-4748 Kamaya 219-489-1533 219-489-2261 Murata Electronics 800-831-9172 814-238-0490 Toko 408-432-8281 408-943-9790 PART TEMP. RANGE MAX2235EVKIT -40°C to +85°C IC PACKAGE 20 TSSOP-EP Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION C1 1 100pF, 5% ceramic capacitor (0603) Murata GRM39COG101J050V C14 1 11pF, 5% ceramic capacitor ATC 100A110JW150X C2 1 68pF, 5% ceramic capacitor (0603) Murata GRM39COG680J050V C15 1 0.01µF, 10% ceramic capacitor (0805) Murata GRM40X7R103K050V C3, C4 2 1000pF, 10% ceramic capacitors (0603) Murata GRM39X7R102K050V C16 1 1µF, +80%, -20% ceramic capacitor (1206) Murata GRM42-6Y5V105Z025V C5, C6 2 100pF, 5% ceramic capacitors (0402) Murata GRM36COG101J050V C17, C18 2 C7 1 22pF, 5% ceramic capacitor (0603) Murata GRM39COG220J050V 1000pF, 10% ceramic capacitors (0805) Murata GRM40X7R102K050V L1 1 8.2nH (0603) inductor Toko LL1608-FH8N2K L3 1 30-gauge wire short J1, J2 2 SMA connectors (PC edge mount) E.F. Johnson 142-0701-801 J3, J4 2 Test points JU1 1 3-pin header (0.1" centers) R1 1 0Ω resistor (0603) Kamaya RMC16-000T VCTRL 1 1-pin header U1 1 MAX2235EUP (TSSOP-20) None 1 MAX2235 EV kit PC board C8 1 0.068µF, 10% Murata GRM39X7R683K016V C9, C10 2 470pF, 10% ceramic capacitors (0603) Murata GRM39X7R471K050V C11 1 220pF, 5% ceramic capacitor (0603) Murata GRM39COG221J050V C12 1 1500pF, 10% ceramic capacitor (0603) Murata GRM39X7R152K0504 C13 1 47pF, 5% ceramic capacitor ATC 100A470JW150X ________________________________________________________________ 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: MAX2235 Features General Description Evaluates: MAX2235 MAX2235 Evaluation Kit Quick Start The MAX2235 EV kit is fully assembled and factory tested. Follow the instructions in the Connections and Setup section for proper device evaluation. Test Equipment Required This section lists the recommended test equipment to verify operation of the MAX2235. It is intended as a guide only, and some substitutions are possible. • One RF signal generator capable of delivering at least +10dBm of output power at the operating frequency (HP8648C, or equivalent) • One RF power sensor capable of handling at least +20dBm of output power at the operating frequency (HP8482A, or equivalent) • One RF power meter capable of measuring up to +20dBm of output power at the operating frequency (HP EPM-441A, or equivalent) • An RF spectrum analyzer that covers the operating frequency range of the MAX2235 as well as a few harmonics (HP8561E, for example) • A power supply capable of up to 1A at +2.7V to +5.5V • An optional ammeter for measuring the supply current • Two 50Ω SMA cables • One SMA 20dB pad • Network Analyzer (HP8753D, for example) to measure small-signal return loss and gain (optional) Connections and Setup This section provides a step-by-step guide to operating the EV kit and testing the device’s function. Do not turn on the DC power or RF signal generators until all connections are made. 2) Connect one RF signal generator to the RFIN SMA connector; do not turn on the generator’s output. Set the generator for an output frequency of 836MHz at a power level of 0dBm. 3) Connect a 20dB pad to the RFOUT SMA connector on the EV kit. This is to prevent overloading of the power sensor and the power meter. 4) Connect a power sensor to the 20dB pad. 5) Connect the power sensor to a power meter. Set the power meter offset to 20dB and frequency to 836MHz. 6) Turn on the DC supply. The supply current should read approximately 70mA. 7) Activate the RF generator’s output. The power meter should read approximately +30dBm. The supply-current should increase to approximately 600mA. 8) Another method for determining gain is by using a Network Analyzer (optional). This has the advantage of displaying gain versus a swept-frequency band, in addition to displaying input and output return loss. Refer to the Network Analyzer manufacturer’s user manual for setup details. Layout Issues A good PC board (PCB) is an essential part of an RF circuit design. The EV kit PCB can serve as a guide for laying out a board using the MAX2235. Keep traces carrying RF signals as short as possible to minimize radiation and insertion loss due to the PCB. Each VCC node on the PCB should have its own decoupling capacitor. This minimizes supply coupling from one section of the IC to another. A star topology for the supply layout, in which each VCC node on the circuit has a separate connection to a central VCC node, can further minimize coupling between sections of the IC. 1) Connect a DC supply set to +3.6V (through an ammeter if desired) to the VCC and GND terminals on the EV kit. Do not turn on the supply. 2 _______________________________________________________________________________________ MAX2235 Evaluation Kit SMA 1 2 3 VCC 4 C3 1000pF 5 C5 C6 C7 100pF 100pF 22pF 6 7 8 VCC 9 C11 220pF C4 1000pF 10 RFIN VCTAL GND SHDN VCC GND VCC GND 20 C10 470pF JU2 C17 1000pF VCC 3 19 18 2 C9 470pF C18 1000pF JU1 1 R1 0Ω 17 VCC VCC MAX2235 OUT GND OUT GND GND VCC GND VCC VREF GND RAMP 16 SHORT 15 C13 47pF C12 1500pF C2 68pF J2 14 SMA C14 11pF 13 12 11 C8 0.068µF VCC J3 C15 0.01µF C16 1µF gi J4 e L1 8.2nH st C1 100pF Evaluates: MAX2235 J1 1.0" Pl ea se re Figure 1. MAX2235 EV Kit Schematic Figure 2. MAX2235 EV Kit Component Placement Guide— Component Side 1.0" Figure 3. MAX2235 EV Kit PC Board Layout—Component Side _______________________________________________________________________________________ 3 ea re se P g i l s e te re a gi se st r er eg ! is te 1.0" 1.0" Figure 4. MAX2235 EV Kit PC Board Layout—Ground Plane Pl Pl ea se Evaluates: MAX2235 MAX2235 Evaluation Kit Figure 5. MAX2235 EV Kit PC Board Layout—Power Plane 1.0" Figure 6. MAX2235 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 © 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.