19-1759; Rev 0; 7/00 MAX2645 Evaluation Kit Features ♦ Easy Evaluation of the MAX2645 The MAX2645 is a versatile, high-performance, lownoise amplifier with adjustable IP3. These features allow the MAX2645 to be used in a variety of applications, from a low-noise amplifier to a PA predriver. As assembled, the MAX2645 EV kit is configured for lowest noise figure performance (NF = 2.3dB, IIP3 = +4dBm). A few minor component changes configure the device as a low-noise amplifier with higher linearity and slightly degraded noise figure performance (NF = 2.6dB, IIP3 = +10dBm) or as a PA predriver with high output P1dB performance (output P1dB = +12dBm). Refer to the MAX2645 data sheet for application-specific performance data. ♦ Fully Assembled and Tested ♦ All Critical Peripheral Components Included ♦ SMA Input and Output Connectors ♦ RF Ports Matched to 50Ω at 3.55GHz Ordering Information PART MAX2645EVKIT TEMP. RANGE IC PACKAGE -40°C to +85°C 10 µMAX-EP* *Exposed paddle Component Suppliers SUPPLIER PHONE FAX WEB AVX 843-448-9411 843-448-1943 Avxcorp.com EFJohnson 402-474-4800 402-474-4858 Efjohnson.com Kamaya 219-489-1533 219-489-2261 Kamaya.com Murata 800-831-9172 814-238-0490 Murata.com Taiyo Yuden 800-348-2496 847-925-0899 T-Yuden.com Toko 800-PIK-TOKO 708-699-1194 Tokoam.com Component List DESIGNATION QTY DESCRIPTION C1 1 1.5pF ±0.1pF ceramic capacitor (0402) Murata GRM36COG1R5B050 C2 1 220pF ±10% ceramic capacitor (0402) Murata GRM36X7R221K050 C3 1 47pF ±5% ceramic capacitor (0402) Murata GRM36COG470J050 C4 1 0.75pF ±0.1pF ceramic capacitor (0402) Murata GRM36COGR75B050 C5, C6, C8 3 0.1µF ±10% ceramic capacitors (0603) Murata GRM39X7R104K016 C7 1 10µF, 16V tantalum capacitor AVX TAJC106K016 C9 1 1000pF ±10% ceramic capacitor (0402) Murata GRM36X7R102K050 Z1 1 1.8nH inductor Toko LL1005-FH1N8S DESIGNATION QTY DESCRIPTION R1 1 20kΩ ±1% resistor (0603) R2, R3 2 1kΩ ±5% resistors (0603) JU1, JU2 2 3-pin headers None 2 Shunts (JU1, JU2) J1, J2 2 Test points (VCC, GND) J3, J4 2 SMA connectors (edge mount) EFJohnson 142-0701-801 U1 1 MAX2645EUB None 1 MAX2645 PC board (GETek) None 1 MAX2645 data sheet None 1 MAX2645 EV kit data sheet ________________________________________________________________ Maxim Integrated Products 1 For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800. For small orders, phone 1-800-835-8769. Evaluates: MAX2645 General Description The MAX2645 evaluation kit (EV kit) simplifies evaluation of the MAX2645 3.4GHz to 3.8GHz low-noise amplifier/PA predriver. The EV kit is fully assembled and tested, allowing simple evaluation of all device functions. All RF signal ports use SMA connectors, providing a convenient interface to RF test equipment. Evaluates: MAX2645 MAX2645 Evaluation Kit • Test Equipment Required Optional: Power meter for calibrating system measurements (HP 438A for example) This section lists the test equipment required for evaluating the MAX2645: • Connections and Setup This section provides step-by-step instructions for setting up the EV kit and ensuring proper operation: One DC power supply capable of supplying 20mA of supply current over the supply voltage range +3.0V to +5.5V • One RF-signal generator or equivalent (50Ω) sinewave source capable of delivering at least -10dBm of output power up to 3.8GHz (HP 8648, for example) • One RF-spectrum analyzer or equivalent with a frequency range of at least 4GHz (HP 8561E, for example) • Two 50Ω SMA cables (RG-58A/U or equivalent) • Optional: Digital multimeters (DMMs) to monitor DC supply voltage and supply current 1 2 1) DC Power Supply: Set the DC power supply voltage to +3.3V. Turn the power supply off and connect it to the VCC and GND connections on the EV kit. If desired, place an ammeter in series with the power supply to measure supply current and a voltmeter in parallel with the VCC and GND connections to measure supply voltage at the device. 2) RF Signal Generator: Connect one of the 50Ω SMA cables to the RF output of the signal generator. Set the RF frequency of the signal generator to 3.55GHz at an output power level of -20dBm. To improve measurement accuracy, use a power VCC GND GAIN GND C3 47pF R3 1k 9 VCC 1 GAIN 0 JU1 C8 0.1µF MAX2645 RFIN C1 3 RFIN SHDN 8 R2 1k 1 SHDN 0 JU2 C8 0.1µF Z1 4 GND 5 C2 220pF VCC C10 10µF C6 0.1µF BIAS GND RFOUT 7 8 RADIAL STUB * 40° 294 TLINE mil s LEQUIV = 1.5nH VCC C9 1000pF R1 RFOUT C4 0.75pF APPLICATION CIRCUIT LNA, LOW NF LNA, HIGH INPUT IP3 PA PREDRIVER C1 Z1 1.5pF 1000pF 0.01µF 1.8nH 0.75pF 0.75pF RBIAS (kΩ) VCC (V) 20 3.3 20 15 3.3 5.0 * BOARD MATERIAL = GETek, COPPER THICKNESS = 1 oz BOARD THICKNESS = 0.012in, DIELECTRIC CONSTANT = 3.8 Figure 1. MAX2645 EV Kit Schematic 2 _______________________________________________________________________________________ MAX2645 Evaluation Kit 3) Spectrum Analyzer: Connect the spectrum analyzer to the RFOUT port of the MAX2645 EV kit using a 50Ω SMA cable. Set the center frequency of the spectrum analyzer to 3.55GHz, the frequency span to 1MHz, and the reference level to 0dBm. To improve measurement accuracy, calibrate out any cable losses and spectrum analyzer offsets. 4) Jumper Connections: To enable the MAX2645, connect the SHDN jumper (JU2) on the EV kit to the “1” position (SHDN = VCC). To place the MAX2645 in high-gain mode, connect the GAIN jumper (JU1) on the EV kit to the “1” position (GAIN = VCC). Analysis Turn on the power supply, then the RF signal generator. The ammeter should read approximately 9.2mA, and the spectrum analyzer should show an output power of approximately -6dBm in high-gain mode. Be sure to take into account cable and board losses when calculating power gain. Typical board losses are 0.5dB at 3.5GHz. To evaluate the MAX2645 in low-gain mode, connect the GAIN jumper (JU1) on the EV kit to the “0” position (GAIN = GND). The ammeter should read approximately 3mA, and the spectrum analyzer should show an output power of approximately -31dBm in low-gain mode. To evaluate the MAX2645 low-power shutdown mode, connect the SHDN jumper (JU2) on the EV kit to the “0” position (SHDN = GND). The ammeter should read approximately 0.1µA. To evaluate the MAX2645 as a low-noise amplifier with higher linearity performance or as a PA predriver, replace capacitor C1, Z1, and resistor R1 with the components recommended in the EV kit schematic (Figure 1). Refer to the MAX2645 data sheet for applicationspecific performance data. Layout and Bypassing The MAX2645 RFOUT output port requires an equivalent 1.5nH of high-impedance transmission line to VCC for proper biasing and matching. This transmission line is terminated at the VCC node with a radial stub for high-frequency bypassing. This arrangement provides a high-Q, low-loss bias network used to optimize performance. The radial stub can be replaced with an appropriate microwave capacitor. Good PC board layout is an essential aspect of RF circuit design. The MAX2645 EV board can serve as a guide for layout of your board. Keep PC board trace lengths as short as possible to minimize parasitics and losses. Keep bypass capacitors as close to the device as possible with low-inductance connections to the ground plane. Refer to the MAX2645 data sheet for more information regarding bypassing. 1.0" 1.0" Figure 2. MAX2645 EV Kit PC Board Layout—Component Placement Guide Figure 3. MAX2645 EV Kit PC Board Layout—Component Side _______________________________________________________________________________________ 3 Evaluates: MAX2645 meter to measure the actual power at the end of the SMA connector. Turn the output of the signal generator off once the output power has been set. Connect the other end of the SMA cable to the RFIN port of the MAX2645 EV kit. Evaluates: MAX2645 MAX2645 Evaluation Kit 1.0" 1.0" Figure 4. MAX2645 EV Kit PC Board Layout—Ground Plane Figure 5. MAX2645 EV Kit PC Board Layout—Power Plane 1.0" Figure 6. MAX2645 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.