MAXIM MAX2643EVKIT

19-1682; Rev 0; 4/00
MAX2642/MAX2643 Evaluation Kits
Features
♦ Easy Evaluation of MAX2642/MAX2643
The MAX2642/MAX2643 EV kits are fully assembled
with the MAX2642 or MAX2643 on board, and incorporate
input matching components optimized for 900MHz
operation.
♦ Fully Assembled and Tested
♦ +2.7V to +5.5V Single-Supply Operation
♦ RF Input and Output Matched to 50Ω at 900MHz
♦ Jumper Included for Gain/Shutdown Setting
Ordering Information
Component List
DESIGNATION
C1
QTY
1
PART
TEMP.
RANGE
MAX2642EVKIT
-40°C to +85°C
SC70-6
AAC
MAX2643EVKIT
-40°C to +85°C
SC70-6
AAD
DESCRIPTION
470pF ±5% ceramic cap (0603)
Murata GRM39X7R471K050 or
Taiyo Yuden UMK107 B471KZ
C2
1
3.3pF ±5% ceramic cap (0603)
Murata GRM39COG3R3B050
C3
0
Not installed
C4, C5
2
100pF ±5% ceramic caps (0603)
Murata GRM39COG101J050 or
Taiyo Yuden UMK107CH101JZ
C6
1
47pF ±5% ceramic cap (0603)
Murata GRM39COG470J050 or
Taiyo Yuden UMK107CH470JZ
C7
1
4.7µF ceramic capacitor (0805)
L1
1
8.7nH inductor (0603)
Coilcraft 0603CS-8N7XJBC
R1
1
511Ω ±1% resistor (0603)
R2
1
33kΩ ± 5% resistor (0603) (MAX2642)
10kΩ ± 5% resistor (0603) (MAX2643)
R3
0
Not installed
R4
1
0Ω resistor
VCC, GND
2
2-pin headers
JU1
0
Not installed
JU2
1
3-pin header
RFIN, RFOUT
2
Edge-mount SMA connectors
U1
1
Maxim MAX2642EXT-T or
MAX2643EXT-T IC (6-pin SC70)
IC
PACKAGE
TOP
MARK
Component Suppliers
SUPPLIERS
PHONE
FAX
WEB
Coilcraft
847-639-6400 847-639-1469
www.coilcraft.
com
Murata
Electronics
800-831-9172 814-238-0490
www.murata.
com
Taiyo Yuden
800-348-2496 408-434-0375
www.
t-yuden.com
________________________________________________________________ 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.
Evaluate: MAX2642/MAX2643
General Description
The MAX2642/MAX2643 evaluation kits (EV kits) simplify
evaluation of the MAX2642 and MAX2643 low-noise
amplifiers (LNAs). These kits enable testing of the
devices’ performance and require no additional support
circuitry. The signal input and output use SMA connectors
to facilitate connection of RF test equipment.
Evaluate: MAX2642/MAX2643
MAX2642/MAX2643 Evaluation Kits
Quick Start
The MAX2642/MAX2643 EV kits are fully assembled and
factory tested. Follow the instructions in the Connections
and Setup section for proper device evaluation.
Test Equipment Required
• An RF signal generator capable of delivering -10dBm
of output power and a frequency range covering the
MAX2642/MAX2643 (800MHz to 1000MHz, for example)
• An RF spectrum analyzer that covers the operating
frequency range
• A DC power supply capable of supplying +2.7V to
+5.5V
• Two 50Ω coaxial cables with SMA connectors
• An ammeter to measure supply current (optional)
• A noise figure meter (optional)
• A network analyzer for measuring gain and return
loss (optional)
Connections and Setup
Checking Power Gain
1) Connect a DC supply (preset to +3.0V) to the VCC
and GND terminals (through an ammeter, if desired)
on the EV kit.
2) Set the RF generator for an output frequency of
900MHz at a power level of -30dBm. Connect the RF
generator’s output to the RFIN SMA connector.
3) Connect the coaxial cable from the RFOUT SMA connector to the spectrum analyzer.
7) Optional: Another method of determining gain is by
using a network analyzer. This has the advantage of
displaying gain vs. a swept frequency band, in addition to displaying input and output return loss. Refer
to the user manual of the network analyzer for setup
details.
Checking Noise Figure
Noise figure measurements on low-noise devices such
as the MAX2642/MAX2643 are extremely sensitive to
board and lab setup losses and parasitics. There are
many techniques and precautions for measuring low
noise figure. A detailed explanation of these items
would exceed the scope of this document. Take into
account PC board and external components loss when
performing noise-figure measurements. The typical
input losses on these EV kits is 0.25dB. For more information on how to perform this level of noise-figure measurement, refer to the noise-figure meter operating
manual and to Hewlett Packard’s application note #57-2,
Noise Figure Measurement Accuracy.
Layout Considerations
Good PC board layout is an essential part of an RF circuit’s design. The EV kit PC board can serve as a guide
for laying out a board using the MAX2642/MAX2643.
Generally, the VCC node on the PC board should have
a decoupling capacitor located close to the device,
and additional capacitors may be needed for long VCC
lines. This minimizes supply coupling. Proper grounding
of the GND pins is essential. Connect the GND pins to
the ground plane either directly, through vias, or both.
4) Turn on the DC supply. The supply current should
read approximately 5mA (if using an ammeter).
5) Activate the RF generator’s output. A signal on the
spectrum analyzer’s display should indicate a typical
gain of +17dB after accounting for cable and board
losses.
6) Optional: For the MAX2642, set the jumper JU2 to the
V CC position. The power gain should now be
+3.5dB.
2
_______________________________________________________________________________________
MAX2642/MAX2643 Evaluation Kits
Evaluate: MAX2642/MAX2643
VCC
JU2
C4
100pF
R3
OPEN
JU1
C3
OPEN
1
RFOUT
BIAS
R2
33k (MAX2642)
10k (MAX2643)
6
RFOUT
SWA
C5
100pF
R1
511Ω
U1
2
RFIN
C1
470pF
L1
8.7nH
SWA
3
GND
RFIN
C2
3.3pF
MAX2642
MAX2643
GND
GND
5
R4
0Ω
VCC 4
C6
47pF
VCC
C7
4.7µF
Figure 1. MAX2642/MAX2643 EV Kit Schematic
_______________________________________________________________________________________
3
Evaluate: MAX2642/MAX2643
MAX2642/MAX2643 Evaluation Kits
1.0"
1.0"
Figure 2. MAX2642/MAX2643 EV Kits Component Placement
Guide—Component Side
1.0"
Figure 3. MAX2642/MAX2643 EV Kits PC Board Layout—
Component Side
1.0"
Figure 4. MAX2642/MAX2643 EV Kits PC Board Layout—
Ground Plane Layers 2 and 3
Figure 5. MAX2642/MAX2643 EV Kits 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.