MAXIM MAX1479EVKIT-433

19-3726; Rev 0; 5/05
MAX1479 Evaluation Kit
The MAX1479 evaluation kit (EV kit) allows for a detailed
evaluation of the MAX1479 ASK/FSK transmitter. It
enables testing of the device’s RF performance and
requires no additional support circuitry. The RF output
uses a 50Ω matching network and an SMA connector for
convenient connection to test equipment. A reverse polarity SMA is also included to connect to a 1/4 wave whip
antenna. The EV kit can also directly interface to the
user’s embedded design for easy data encoding.
The MAX1479EV kit comes in two versions: a 315MHz
version and a 433.92MHz version. The passive components are optimized for these frequencies. These components can easily be changed to work at RF frequencies
from 300MHz to 450MHz.
For easy implementation into the customer’s design, the
MAX1479EV kit also features a proven PC board layout,
which can be easily duplicated for quicker time-tomarket. The EV kit Gerber files are available for download at www.maxim-ic.com.
Features
♦ Proven PC Board Layout
♦ Proven Components Parts List
♦ Multiple Test Points Provided on Board
♦ Available in 315MHz or 433.92MHz Optimized
Versions
♦ Adjustable Frequency Range from 300MHz to
450MHz*
♦ Fully Assembled and Tested
♦ Can Operate as a Stand-Alone Transmitter with
Included Battery
*Requires component changes.
Ordering Information
PART
TEMP RANGE
IC PACKAGE
MAX1479EVKIT-315
-40°C to +85°C
16 Thin QFN
MAX1479EVKIT-433
-40°C to +85°C
16 Thin QFN
Component List
DESIGNATION QTY
DESCRIPTION
DESIGNATION QTY
DESCRIPTION
C7, C9
2
0.47µF +80/-20%, 16V ceramic
capacitors (0603) Y5V
Murata GRM188F51C474Z
6.8pF ±0.5pF, 50V ceramic capacitors
(0603) C0G
Murata GRM1885C1H6R8D
C8, C11, C12
3
220pF ±5%, 50V ceramic capacitors
(0603)
Murata GRM1885C1H221J
1
22pF ±5%, 50V ceramic capacitor
(0603) C0G
Murata GRM1885C1H220J
C13 (315MHz)
1
2.2pF ±0.5pF, 50V ceramic capacitor
(0603) C0G
Murata GRM1885C1H2R2D
C2 (433MHz)
1
10pF ±5%, 50V ceramic capacitor
(0603) C0G
Murata GRM1885C1H100J
C13 (433MHz)
1
1.0pF ±0.5pF, 50V ceramic capacitor
(0603) C0G
Murata GRM1885C1H1R0D
C3, C10
2
0.01µF ±10%, 50V ceramic capacitors
(0603)
Murata GRM188R71H103KA01
C14, C15
2
100pF ±5%, 50V ceramic capacitors
(0603)
Murata GRM1885C1H101J
C4
1
680pF ±5%, 50V ceramic capacitor
(0603) C0G
Murata GRM1885C1H681J
JU1–JU10
10
3-pin headers
Digi-Key S1012-36-ND or equivalent
L1 (315MHz)
1
27nH ±5% inductor (0603)
Coilcraft 0603CS-27NXJB
L1 (433MHz)
1
22nH ±5% inductor (0603)
Coilcraft 0603CS-22NXJB
C1, C6
(315MHz)
2
15pF ±5%, 50V ceramic capacitors
(0603)
Murata GRM1885C1H150J
C1, C6
(433MHz)
2
C2 (315MHz)
C5, C16,
C18, C19
0
Not installed
________________________________________________________________ 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: MAX1479
General Description
Evaluates: MAX1479
MAX1479 Evaluation Kit
Component List (continued)
DESIGNATION QTY
DESIGNATION QTY
DESCRIPTION
L2 (315MHz)
1
22nH ±5% inductor (0603)
Coilcraft 0603CS-22NXJB
L2 (433MHz)
1
18nH ±5% inductor (0603)
Coilcraft 0603CS-18NXJB
R1
1
5kΩ potentiometer
BC Components SM4W502
R2
0
0Ω resistor (0603), any,
not installed
R3
1
5.1Ω ±5% resistor (0603), any
R4
1
0Ω resistor (0603), any
Antenna
(315MHz)
0
315MHz 1/4-wave whip antenna,
not provided
Lynx ANT-315-CW-RH
Antenna
(433MHz)
1
433MHz 1/4-wave whip antenna,
not provided
Lynx ANT-433-CW-RH
ANTENNA_OUT
1
RP-SMA connector
Linx CONREVSMA001
BAT1
1
Battery holder
MPD BA2032
Battery
1
Coin-cell battery
Panasonic BR2032
DESCRIPTION
REF_IN
1
SMA connector top mount, not installed
Digi-Key J500-ND
Johnson 142-0701-201
RF_OUT
1
SMA connector top mount
Digi-Key J500-ND
Johnson 142-0701-201
U1
1
MAX1479ATE
VDD, VSS,
ENABLE,
DATA_IN,
CKOUT
5
Test points
Mouser 151-203 or equivalent
1
Crystal 9.84375MHz
Hong Kong Crystal
SSL9843750E03FAFZ800 or
Crystek 017000
Y1 (433MHz)
1
Crystal 13.56MHz
Hong Kong Crystal
SSM1356000E03FAFZ800 or
Crystek 017001
—
10
Shunt (JU1)
Digi-Key S9000-ND or equivalent
—
1
MAX1479 EV kit PC board
Y1 (315MHz)
Connections and Setup
Component Suppliers
SUPPLIER
PHONE
FAX
Coilcraft
800-322-2645
847-639-1469
Crystek
800-237-3061
941-561-1025
Hong Kong Crystal
852-2412-0121
852-2498-5908
Murata
800-831-9172
814-238-0490
Note: Indicate you are using the MAX1479 when contacting
these manufacturers.
Quick Start
The following procedure allows for proper device
evaluation.
Required Test Equipment
•
•
•
•
2
Regulated power supply capable of providing +3.0V
Spectrum analyzer such as the Agilent 8562E
Optional ammeter for measuring supply current
Power meter such as the Agilent EPM-441A
This section provides a step-by-step guide to operating
the EV kit and testing the device’s functionality. Do not
turn on the DC power until all connections are made:
1) Connect a DC supply set to +3.0V, through an
ammeter, to the VDD and VSS terminals on the EV
kit. Do not turn on the supply.
2) Connect the RF_OUT SMA connector to the spectrum analyzer. Set the analyzer to a center frequency
of 315MHz (or 433.92MHz) and a span of 1MHz.
3) Turn on the DC supply. The spectrum analyzer
should display a peak of about +10dBm at
315MHz (or 433.92MHz).
4) Disconnect the spectrum analyzer and connect
the power meter instead. Measure the output
power and also the current draw.
5) Calculate the efficiency. This is done using the
following equation:
Efficiency = 10ˆ(POUT/10)/(V x I)
For example, for a +10.8dBm output, and a
10.9mA (at 3.0V) current, the efficiency is 37%.
_______________________________________________________________________________________
MAX1479 Evaluation Kit
A properly designed PC board is an essential part of any
RF/microwave circuit. On high-frequency inputs and outputs, use controlled-impedance lines and keep them as
short as possible to minimize losses and radiation. At
high frequencies, trace lengths that are on the order of
λ/10 or longer can act as antennas.
Keeping the traces short also reduces parasitic inductance. Generally, 1in of a PC board trace adds about
20nH of parasitic inductance. The parasitic inductance
can have a dramatic effect on the effective inductance.
For example, a 0.5in trace connecting a 100nH inductor
adds an extra 10nH of inductance or 10%.
To reduce the parasitic inductance, use wider traces
and a solid ground or power plane below the signal
traces. Also, use low-inductance connections to ground
on all GND pins, and place decoupling capacitors
close to all VDD connections.
The EV kit PC board can serve as a reference design
for laying out a board using the MAX1479.
Detailed Description
Power-Down Control
The MAX1479 can be controlled externally using the
ENABLE connector. The IC draws approximately 0.2nA
(at room temperature) in shutdown mode. Jumper JU1
is used to control this mode. The shunt can be placed
between pins 1 and 2 to enable the device. Remove
the JU1 shunt for external control. See Table 1 for
jumper function descriptions.
Table 1. JU1 Through JU4 Jumpers
Function
JUMPER
JU1
JU2
JU3
JU4
STATE
FUNCTION
1-2
RF carrier transmit enable
2-3
Power-down mode
N.C.
External power-down control
1-2
RF carrier transmit mode (ASK),
FSK high frequency (FSK)
2-3
PA off, PLL ON (ASK),
FSK low frequency (FSK)
N.C.
External data transmit
1-2
External supply operation
2-3
Battery operation
1-2
FSK mode
2-3
ASK mode
Data Input
The MAX1479 EV kit transmits ASK and FSK data with
data rates of up to 100kbps (ASK) or 20kbps (FSK).
JU2 controls whether the MAX1479 transmits the ASK
carrier frequency (or the FSK high frequency), turns off
the PA (or transmits the FSK low frequency), or transmits an external data stream. See Table 1.
REF_IN External Frequency Input
For applications where the correct frequency crystal is
not available, it is possible to directly inject an external
frequency through the REF_IN SMA (not provided).
Connect the SMA to a low-phase-noise generator. The
addition of C18 and C19 is necessary (use 0.01µF
capacitors).
Battery Operation
The MAX1479 EV kit can be powered by an external
power supply or by the supplied 3V coin-cell battery. Set
jumper JU3 to connect pins 2 and 3 for battery operation.
RF Output
The MAX1479 EV kit includes two SMA connectors for
RF output. RF_OUT is a standard SMA and is used to
connect the PA output to test equipment. Output is
matched to 50Ω. ANTENNA_OUT is a reverse polarity
SMA and is used to connect to the 1/4-wave whip
antenna (not supplied). Note that resistor R2 (0Ω)
needs to be added.
Modulation Mode Input
Jumper JU4 sets the mode of transmission. Set jumper
JU4 to connect pins 1 and 2 for FSK mode, 2 and 3 for
ASK mode.
FSK Frequency Deviation
The FSK deviation is set by jumpers JU5 through JU7.
The maximum deviation depends on the PC board parasitics. The EV kit max is around 50kHz (315MHz). If very
large FSK frequency deviations are desired, use a crystal
with a larger motional capacitance and/or reduce PC
board parasitic capacitances. One way to reduce parasitic capacitances on the EV kit is to remove C14, C15,
and C16 and move the crystal closer to the IC.
_______________________________________________________________________________________
3
Evaluates: MAX1479
Layout Issues
Evaluates: MAX1479
MAX1479 Evaluation Kit
Table 2. Clock-Divider Settings
JUMPER
SETTING
JU5
JUMPER
SETTING
JUMPER
SETTING
FUNCTION
1-2
1-2
1-2
Max deviation
1-2
1-2
2-3
7/8 x max deviation
1-2
2-3
1-2
3/4 x max deviation
1-2
2-3
2-3
5/8 x max deviation
JU6
2-3
1-2
JU7
1-2
1/2 x max deviation
2-3
1-2
2-3
3/8 x max deviation
2-3
2-3
1-2
1/4 x max deviation
2-3
2-3
2-3
1/8 x max deviation
Clock Output
Jumpers JU8 and JU9 set the divider ratio for the clock
output. See Table 3 for the settings.
I/O Connections
Table 5 is a list of all I/O connections.
Table 5. I/O Connectors
Table 3. Clock Divider Settings
JUMPER
SETTING
JUMPER
1-2
1-2
JU8
2-3
2-3
JU9
SIGNAL
SETTING
FUNCTION
DESCRIPTION
RF_OUT
RF output
1-2
fXTAL /16
REF_IN
External reference frequency input
2-3
fXTAL /8
ANTENNA_OUT
Reverse polarity SMA for 1/4-wave antenna
1-2
fXTAL /4
VSS
Ground
2-3
Logic 0
output
VDD
Power-supply input
DATA_IN
Data input
ENABLE
Power-down control
CLKOUT
Buffered clock output
Envelope Shaping
Jumper JU10 sets envelope shaping for a more gentle
turn-on/turn-off of the PA in ASK mode. Set jumper
JU10 to connect pins 2 and 3 to allow for envelope
shaping. See Table 4 for settings.
For additional information and a list of application
notes, consult the www.maxim-ic.com website.
Table 4. JU10 Jumper Function
JUMPER
JU10
4
STATE
FUNCTION
1-2
No envelope shaping
2-3
Envelope shaping
_______________________________________________________________________________________
MAX1479 Evaluation Kit
C15
100pF
Y1*
C19
OPEN REF_IN
1
50Ω OUTPUT
2
C16
OPEN
14
XTAL1
XTAL2
15
AT 315MHz
AT 433.92MHz
C1
15pF
6.8pF
C2
22pF
10pF
C6
15pF
6.8pF
C13
2.2pF
1.0pF
L1†
27nH
22nH
L2†
22nH
18nH
Y1
9.84375MHz
13.56MHz
C5
OPEN
VDD
GND
JU4
*
†USE WIRE-WOUND INDUCTORS ONLY.
C18
OPEN
1
2
3
2
MODE
VSS
16
U1
R3
5.1Ω
MAX1479
VDD
DATA_IN
1
2
JU2
VDD
3
1
C7
0.47µF
C11
220pF
4
BAT1
6
ENABLE
3
ROUT
7
3
1
2
3
R1
5kΩ
C9
0.47µF
JU10
C8
220pF
C3
0.01µF
C12
220pF
C4
680pF
1
2
CKOUT
L1*
L2*
C1*
5
1
2
3
R4
0Ω
VDD
JU1
JU3
DIN
VDD_PA
1
2
VDD
VDD
C10
0.01µF
3
ENABLE
Evaluates: MAX1479
C14
100pF
CLKOUT
PAOUT
CLK0
CLK1
DEV0
DEV1
DEV2
9
10
11
12
13
VDD
VDD
VDD
JU7
JU9
JU5
1 2 3
1 2 3
VDD
1 2 3
RF_OUT
1
8
C13*
C2*
2
C6*
R2
OPEN
ANTENNA_OUT
1
2
VDD
JU8
1 2 3
JU6
1 2 3
Figure 1. MAX1479 EV Kit Schematic
_______________________________________________________________________________________
5
Evaluates: MAX1479
MAX1479 Evaluation Kit
Figure 2. MAX1479 EV Kit Component Placement Guide—
Component Side
Figure 3. MAX1479 EV Kit PC Board Layout—Component Side
Figure 4. MAX1479 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.
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© 2005 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.