Maxim MAX2102EVKIT-SO Evaluation kit Datasheet

19-1256; Rev 2; 10/98
MAX2102 Evaluation Kit
The board includes RF and LO inputs and I/Q baseband-output connectors, for fast evaluation in a 50Ω
environment. The RF and LO input frequency range is
950MHz to 2150MHz. A probe-tip jack is available to
examine the prescaler output with a high-impedance
probe.
____________________________Features
♦ Simple RF Test Board Offers 50Ω Test Ports for
RF and LO Inputs and Baseband Outputs
♦ Direct-Conversion Signal Tuning from 950MHz to
2150MHz, to I/Q Baseband
♦ Input Levels: -69dBm to -19dBm per Carrier
♦ Allows Testing of 50dB Automatic Gain-Control
Range
♦ Permits Observation of Dual-Modulus Prescaler
Output
Component Suppliers
SUPPLIER
PHONE
♦ Fully Assembled and Tested
FAX
AVX
(803) 946-0690
(803) 626-3123
Panasonic
(201) 392-7522
(201) 392-4441
Ordering Information
PART
TEMP. RANGE
BOARD TYPE
MAX2102EVKIT-SO
0°C to +70°C
Surface Mount
Component List
DESIGNATION QTY
B1–B5
C1, C9
C2, C3,
C8, C11
DESCRIPTION
5
Surface-mount bead cores
Panasonic EXC-CL3216U
2
47µF, 10V, ±20% electrolytic capacitors
Panasonic ECE-V1AA470P
4
0.1µF, 50V (min), 10% ceramic
capacitors
6
22pF, 50V (min), 10% ceramic
capacitors
C10, C12
2
10pF, 50V (min), 10% ceramic
capacitors
C13, C16
2
10pF, 50V (min), 10% ceramic
capacitors
C17, C19, C21,
C22
4
1000pF, 50V (min), 10% ceramic
capacitors
C20
1
10µF, 16V, ±20% tantalum capacitor
AVX TAJC106M106
C26, C27
2
0.22µF, 50V (min), 10% ceramic
capacitors
J1, J3
2
BNC connectors
C4–C7,
C14, C15
DESIGNATION QTY
DESCRIPTION
J2, J4, J5
3
Edge-mount SMA connectors
J6
1
Scope-probe connector
JU2, JU3
2
3-pin headers (0.1" centers)
Shunts
R1, R7
2
47Ω, 5% resistors
R3, R13
2
Open
R4, R16
2
51Ω, 5% resistors
R6
1
2kΩ, 5% resistor
R8, R10
2
22Ω, 5% resistors
R11, R12
2
56Ω, 5% resistors
R15
1
100Ω, 5% resistor
R17
1
4.7Ω, 5% resistor
U1
1
Maxim MAX2102CWI (28-pin SO)
None
1
MAX2102 circuit board
None
1
MAX2102 data sheet
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Evaluates: MAX2102
General Description
The MAX2102 evaluation kit (EV kit) simplifies evaluation of the MAX2102 direct-conversion tuner IC for digital DBS applications.
Evaluates: MAX2102
MAX2102 Evaluation Kit
__________Test Equipment Required
• RF-signal generator to generate the RF-carrier signals, with 950MHz to 2150MHz frequency range and
-69dBm to -19dBm power range.
• RF-signal generator to generate the LO signal, with
950MHz to 2150MHz frequency range at -10dBm.
• (Optional) RF balun, such as Anzac H-9, if testing
the MAX2102 with a differential LO drive.
• Dual-channel digitizing oscilloscope with 50Ω terminated inputs and 100MHz minimum bandwidth for
time-domain baseband measurements. In addition,
a high-frequency, high-impedance probe is required
if monitoring the prescaler.
• Network/spectrum analyzer capable of measuring
30kHz to 100MHz signals for frequency-domain
baseband measurements.
• +5V power supply that can deliver a minimum of
300mA.
• Adjustable voltage source that can supply a 1V to
4V range and source and sink 500µA for automatic
gain control (AGC).
Connections and Setup
Ensure that the RF signal generators are disabled, and
that the power supplies are off until all connections are
made.
1) Connect the +5V power supply to J7 (“VCC”).
Connect ground to J8 (“GND”).
2) Ensure that there are no shunts installed at JU2 or
JU3.
3) Connect the variable voltage source to the pad
labeled “AGC.” Ensure that the voltage source’s
ground is connected to J8.
4) Connect an SMA cable from the LO signalgenerator source to SMA connector J4 (LO) on the
board. A 6dB attenuator connected in-line between
J4 and the cable is recommended to minimize
reflections that could affect power-level control on
some signal generators. See the section Using a
Differential Oscillator Source for information on driving the LO port differentially.
5) Connect an SMA cable from the RF-carrier signalgenerator source to SMA connector J2 (RFIN).
A 6dB pad between J2 and the cable is recommended.
6) Connect two cables of equal length from the dualchannel oscilloscope inputs to BNC connectors J1
and J3 (“IOUT,” “QOUT”). Ensure that the oscilloscope inputs are 50Ω.
2
7) Set up the instruments:
—Set the RF-carrier signal source to deliver
950MHz at -30dBm at RFIN. Be sure to account
for attenuator and cable losses.
—Set the LO signal source to deliver 950.125MHz
at -10dBm at LO. Be sure to account for attenuator and cable losses.
—Set up the oscilloscope to view a 125kHz sine
wave at 0.5Vp-p full scale, triggered from either
the “IOUT” or “QOUT” signal.
8) Turn on the power supplies and enable the signal
generators.
9) Adjust the AGC control voltage until the IOUT and
QOUT signals are approximately 0.25Vp-p.
Analysis
AGC
Vary the RF-carrier signal-generator power over the
-19dBm to -69dBm range. Use the AGC voltage control
(in a 1V to 4V range) to keep the IOUT and QOUT signals in the 0.25Vp-p range.
Note (from the EV kit schematic) that the board includes 47Ω resistors (R1, R7) in series with the baseband IOUT and QOUT outputs, which results in a 6dB
attenuation with the cable terminated to 50Ω at the
oscilloscope. The actual voltage swing per carrier is
0.5Vp-p at the MAX2102’s IOUT and QOUT pins.
Vary the LO and RFIN frequency over the 950MHz to
2150MHz range, maintaining 125kHz between RFIN
and LO. Observe that over 50dB, AGC range is maintained across the frequency band.
Quadrature Accuracy
The difference in phase between the IOUT and QOUT
baseband signals should be 90°, with Q lagging I if the
LO frequency is greater than the RFIN frequency.
Using both the oscilloscope’s DELAY measurement
function and averaging, determine the quadrature
phase mismatch (deviation from 90°).
The baseband frequency is 125kHz. At higher baseband frequencies, the delay between IOUT and QOUT
becomes more difficult to measure accurately.
Additionally, phase error due to small differences in
group delay in IOUT and QOUT measurement channels
becomes more pronounced. Therefore, low baseband
frequencies are suggested when making this measurement.
_______________________________________________________________________________________
MAX2102 Evaluation Kit
Adjustments and Control
Prescaler
Jumper JU2 controls prescaler enabling and disabling.
The prescaler on the MAX2102 EV kit is configured to
be disabled as shipped. In this configuration, there is
no short installed on JU2. To enable the prescaler,
install a short in the “PSON” position. This connects pin
25 on the MAX2102 to GND.
JU3 controls the prescaler divider ratio (modulus).
Install a short in the “DIV65” position for divide-by-65
mode, or in the “DIV64” position for divide-by-64 mode.
For external control of the prescaler modulus (for example, from an external synthesizer), drive JU3’s center
connector directly.
Using a Differential Oscillator Source
To use a differential LO source, do the following:
1) Remove R16.
3) Connect the RF balun so that LO and LO are driven
by complementary signals. Drive the balun input
from the LO signal source. Ensure that any unused
ports on the balun are terminated with 50Ω terminators.
A 6dB attenuator connected in-line between the LO
and LO ports and the balun is recommended to
minimize reflections, which may affect balun and
signal-generator performance.
4) Drive the balun with sufficient power to drive LO
and LO with -10dBm each. Be sure to account for
losses in the balun, cables, and attenuators.
Interface to MAX1002/MAX1003
A/D Converters
The MAX2102 EV kit can easily be interfaced to the
MAX1002/MAX1003 EV kit, allowing evaluation of the
MAX2102 in the digital domain. The MAX1002/
MAX1003 are low-cost, dual, 60Msps/90Msps analogto-digital converters for DBS applications.
For most applications, an anti-aliasing lowpass filter is
inserted in the signal path between IOUT (MAX2102 EV
kit) and IIN+ (MAX1002/MAX1003 EV kit), and another
equivalent filter is inserted between QOUT and QIN+.
Refer to the MAX2102/MAX2105 data sheet for details
on this filter.
Using 50Ω filters with BNC connectors is a simple way
to implement the necessary filtering.
2) Install J5 (SMA connector), if not already populated.
_______________________________________________________________________________________
3
Evaluates: MAX2102
The quadrature amplitude mismatch is:
Amplitude mismatch = 20log (AI / AQ)
where AI = IOUT signal amplitude, and AQ = QOUT
signal amplitude.
Vary the LO and RFIN frequency over the 950MHz to
2150MHz range, maintaining 125kHz between RFIN
and LO. Observe that the quadrature phase and gain
mismatch remains within the specifications across the
band.
4
IOUT
J1
VCC
BNC
QOUT
J3
AGC
RFIN
C4
22pF
R7
47Ω
C2
0.1µF
C1
47µF
J8
SMA
B1
BNC
47Ω
R1
GND
VCC
J7
J2
C8
0.1µF
C9
47µF
R3
OPEN
C22
1000pF
C7
R4 22pF
51Ω
B2
C21
1000pF
C5
22pF
VCC
C6, 22pF
VCC
C20
10µF
C11
0.1µF
C3
0.1µF
VCC
1
2
3
4
5
6
7
8
9
10
11
12
C10 13
10pF
14
C12
10pF
R17
4.7Ω
VCC
B5
VCC
MOD
IOUT
PSOUT
GND
PSGND
VCC
GND
GND
VCC
VCC
U1
RFIN
LO
RFIN
LO
MAX2102 V
GND
CC
AGC
GND
GND
IDC
GND
IDC
QOUT
QDC
VCC
QDC
VCC
VCC
VCC
24
23
22
21
20
19
18
17
16
15
28
27
26
25
C17
1000pF
C19
1000pF
DIV 65
1
2
R15
100Ω
DIV 64
3
C26
0.22µF
JU3
C27
0.22µF
C13
10pF
C16
10pF
2
JU2
B3
C14, 22pF
C15, 22pF
B4
R6
2k
PSON
1
VCC
PSOFF
3
R11
56Ω
VCC
J6
R8
22Ω
R16
51Ω
R10
R12 22Ω
56Ω
PSOUT
R13
OPEN
J4
J5 SMA
SMA
LO
LO
Evaluates: MAX2102
MAX2102 Evaluation Kit
Figure 1. MAX2102 EV Kit Schematic
_______________________________________________________________________________________
MAX2102 Evaluation Kit
Evaluates: MAX2102
1.0"
1.0"
Figure 2. MAX2102 EV Kit Component Placement Guide—
Component Side
Figure 3. MAX2102 EV Kit Component Placement Guide—Solder
Side
_______________________________________________________________________________________
5
Evaluates: MAX2102
MAX2102 Evaluation Kit
1.0"
Figure 4. MAX2102 EV Kit PC Board Layout—Component Side
6
1.0"
Figure 5. MAX2102 EV Kit PC Board Layout—Ground Plane
_______________________________________________________________________________________
MAX2102 Evaluation Kit
Evaluates: MAX2102
1.0"
1.0"
Figure 6. MAX2102 EV Kit PC Board Layout—Power Layer
Figure 7. MAX2102 EV Kit PC Board Layout—Solder Side
_______________________________________________________________________________________
7
Evaluates: MAX2102
MAX2102 Evaluation Kit
NOTES
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.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1998 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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