19-3325; Rev 0; 7/04
MAX2745 Evaluation Kit
General Description
The MAX2745 evaluation kit (EV kit) simplifies evalua-
tion of the MAX2745 global positioning system (GPS),
radio frequency (RF), front-end IC. 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.
♦
Easy Evaluation of the MAX2745
♦
+2.4V to +3.6V Single-Supply Operation
♦
Jumpers for Digital Control and Shutdown
♦
All Critical Peripheral Components Included
Features
Evaluates: MAX2745
Component Suppliers
SUPPLIER
Alpha
ATC
CoilCraft
Kayama
Murata
PHONE
360-647-2360
949-583-9119
847-639-6400
219-489-1533
770-436-1300
FAX
360-671-4936
949-583-9213
847-639-1469
219-489-2261
770-436-3030
PART
MAX2745EVKIT
Ordering Information
TEMP RANGE
-40°C to +85°C
IC PACKAGE
48 TQFP-EP*
*EP
= Exposed paddle.
**These
components are for internal test purposes.
***These
are the optional components. See the instructions on
the schematic for more details.
Note:
Indicate you are using the MAX2745 when contacting
these manufacturers.
DESIGNATION
C1, C3, C6, C7,
C9–C15, C17,
C22, C33, C53,
C54,
C109–C114
C2, C23, C32
C4, C8
C5
C16, C59, C60
C18, C19
C27–C30,
C48–C51
C36, C43, C47,
C52
C66
C80
C81, C100
QTY
DESCRIPTION
DESIGNATION
C98
22
100nF
±10%
(0402) capacitors
Murata GRM155R61A104K
C101
C102
C105, C106
C107
F5
QTY
1
1
1
2
1
1
Component List
DESCRIPTION
1.0µF
±20%
(0603) capacitor
Taiyo Yuden JMK107BJ105MA-B
10pF
±0.5pF
(0402) capacitor
Murata GRM1555C1H100B
1pF
±0.1pF
(0402) capacitor
Murata GRM1555C1H1R0B
1.0µF
±10%
(2012) capacitors
AVX TAJR105K016
10nF
±10%
(0402) capacitor
Murata GRM155R71C103K
1.575GHz GPS RF saw filter
Murata SAFSE1G57AB0T00R00
Connector DSUB 25-R
DB25 M PC board connector
AMP 747238-4
Open, SMA edge-mount connectors
SMA edge-mount connectors
Johnson 142-0701-801
Shunts
Digi-Key S9000-ND
2-pin headers, 0.1in center
Sullins PTC36SAAN
3-pin headers, 0.1in center
Sullins PTC36SAAN
3
2
1
3
2
0**
4
1
0***
2
100pF
±5%
(0402) capacitors
Murata GRM1555C1H101J
220pF
±10%
(0402) capacitors
Murata GRM155R71H221K
1000pF
±10%
(0402) capacitor
Murata GRM155R71H102K
1500pF
±10%
(0402) capacitors
Murata GRM155R71H152K
39pF
±5%
(0402) capacitors
Murata GRM1555C1H390J
Open (0402) capacitors
22pF
±5%
(0402) capacitors
Murata GRM1555C1H220J
12pF
±5%
(0402) capacitor
Murata GRM1555C1H120J
Open
±10%
(0402) capacitor
Murata
6800pF
±10%
(0402) capacitors
Murata GRM155R71E682K
J5
J19–J22,
J35–J38
J24, J26, J28,
J33, J34
JP1–JP12
JP1–JP6, JP12
JP7–JP11
1
0**
5
12
7
5
________________________________________________________________
Maxim Integrated Products
1
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.
MAX2745 Evaluation Kit
Evaluates: MAX2745
Component List (continued)
DESIGNATION
L58
L60
R1
R5, R8
R6, R18, R19,
R20, R27, R69,
R70, R77
R9
R10–R13
R14–R17
R22–R25
R59
R62
R71
R79–R86
QTY
1
0***
1
2
8
1
4
4
0**
0***
1
1
8
DESCRIPTION
8.2nH
±0.1nH
(0402) inductor
Murata LQP15MN8N2B02
Open
±0.1nH
(0402) inductor
Murata
70kΩ
±1%
(0402), 1/16W resistor
820Ω
±1%
(0402), 1/16W resistors
0Ω
±1%
(0402), 1/16W resistors
100kΩ
±1%
(0402), 1/16W resistor
200Ω
±1%
(0402), 1/16W resistors
10kΩ
±1%
(0402), 1/16W resistors
Open,
±1%,
1/16W resistors
Open,
±1%
(0402), 1/16W resistor
22.1kΩ
±1%
(0402), 1/16W resistor
220Ω
±5%
(0402), 1/10W resistor
30kΩ
±1%
(0402), 1/16W resistors
Y1
1
U12
1
DESIGNATION
S2, S3
TP1–TP5
U1
U3
QTY
2
5
0***
1
DESCRIPTION
DIP switches SW4 SMT
CTS 204-12ST
Test points, PC mini, 0.040 red
Digi-key 5000K-ND
Open TXCO, 16.367667MHz, SM
Rakon
MAX2745ECM IC, GPS RF, SM
Maxim MAX2745ECM
MAX8510EXK27 low-noise linear
regulator
Maxim MAX8510EXK27
Hex buffer/driver with open drain
Texas Instruments SN74LV07ADR
16.368327MHZ XTL
Rakon IDD30UM-1SJ
16.367MHz/XZB548
U4
1
**These
components are for internal test purposes.
***These
are the optional components. See the instructions on the schematic for more details.
Detailed Description
The MAX2745 EV kit simplifies evaluation of the
MAX2745 GPS RF front-end IC. 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. In this section, detailed descriptions of
the EV board as well as the control interface/software
are given to facilitate better evaluation of the IC.
• VDD5V (JP12) is the power supply for the I
2
C* con-
trol interface. It is not required if the control interface
is not used.
I/O Ports
The MAX2745 EV kit has one RF input port, three IF out-
put ports, one clock output port, and one PC control port.
• RF_IN (J24) is the GPS RF signal input port with
SMA connector.
• VCMOUT_1P/VCMOUT_1N/DOUT are the IF out-
put ports.
• CKOUT is the 16MHz/32MHz clock output port.
• J5 is the 25-pin PC parallel control port.
DC Power Supply
The MAX2745 EV kit requires three different pow-
er supplies:
• VINDC (JP3) is the main power supply for the
MAX2745 IC and the external RF circuitry such as
the TCXO. This VINDC supply powers the MAX8510
LDO, which produces 2.85V output with extremely
low noise. If different supply voltages are desired to
test the IC, bypass the LDO and directly power the
board through JP2. See the
Jumper Description
sec-
tion for more details.
• VDD18 (JP1) is the 1.6V to 2.3V supply voltage
needed to test the voltage booster section. Do not
use VDD18 for normal operation. See the
Jumper
Description
section for more details.
2
Digital Controls
There are two DIP switches (S2, S3) on the MAX2745
EV kit that provide eight digital controls. Refer to the
MAX2745 data sheet for more details.
*Purchase
of I
2
C components from Maxim Integrated Products,
Inc., or one of its sublicensed Associate Companies, conveys
a license under the Philips I
2
C Patent Rights to use these com-
ponents in an I
2
C system, provided that the system conforms
to the I
2
C Standard Specification as defined by Philips.
_______________________________________________________________________________________
MAX2745 Evaluation Kit
Jumper Description
There are eight jumpers on the MAX2745 EV kit besides
the power-supply jumpers.
1) JP9—SHDN. Connect pin 2 to pin 3 (GND) for nor-
mal operation.
2) JP7—TCXO power supply. By default the MAX2745 EV
kit uses a 16MHz crystal, so leave this jumper open.
3) JP5—External LNA supply. Refer to the MAX2745
data sheet for more details.
4) JP6—Short this jumper when testing the voltage
booster. When JP6 is shorted, JP2 MUST be open
and 1.6V to 2.3V supply is expected at JP1
(VDD18).
5) JP10—Reserved. Pin 2 MUST be shorted to pin 1
(GND) for normal operation.
6) JP8—Voltage booster enable. Short pin 2 to pin
3 (VDD) to disable the voltage booster (nor-
mal operation).
7) JP11—SHDN of the MAX8510 LDO. Connect pin
2 to pin 1 (VDD) to enable the MAX8510 (nor-
mal operation).
8) JP2—Short this jumper to connect the MAX8510 LDO
output to the power supply of the EV board. If a supply
voltage other than 2.85V is desired, leave JP2 open
and connect the new supply voltage to pin 1 of JP2.
When the voltage booster is enabled, JP2 MUST be
open and NO supply is allowed on either pin.
• Two power supplies capable of up to 1A at +1.6V to
+6.0V
• One ammeter for measuring the supply current
(optional)
• 50Ω SMA cables
• A network analyzer (HP 8753D, for example) to mea-
sure small-signal return loss and gain (optional)
• An oscilloscope to check the digital IF output
Evaluates: MAX2745
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:
1) Connect a DC supply set to +3.3V to the VDC and
GND terminals on the EV kit. Do not turn on the supply.
2) Connect a DC supply set to +5.0V to the 5VDC on
the EV kit. Do not turn on the supply.
3) Connect one RF signal generator to the RFIN SMA
connector; do not turn on the generator’s output.
Set the output frequency to 1575.420000MHz. Set
the power level to -120dBm.
4) Connect the ACOMOUT+/- output on the EV kit to a
spectrum analyzer through an SMA cable.
5) Connect the EV kit to a PC through a parallel cable.
6) Run the control software on an IBM-compatible PC.
7) Set the digital controls to the appropriate states
(refer to the MAX2745 data sheet for the digital con-
trol settings).
8) Turn on the DC supplies. The supply current should
read approximately 20mA.
9) Activate the RF generator’s output.
10) Check the IF outputs.
11) Check other features of the MAX2745, e.g., 16MHz
clock output, voltage booster, temperature-sensor
output, etc.
Control Software
The control software is needed to test the VSPORT of
the MAX2745. It is mainly for internal test purposes and
not required for normal operation. Refer to the
MAX2745 data sheet for more details.
Quick Start
The MAX2745 EV kit is fully assembled and factory test-
ed. 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 MAX2745. It is intended as a
guide only, and some substitutions are possible.
• An RF signal generator capable of delivering RF
power as low as -120dBm and as high as 0dBm at
the 1575.42MHz operating frequency (HP E4433B,
or equivalent)
• An RF spectrum analyzer that covers the MAX2745
operating frequency range, as well as a few harmon-
ics (FSEB20, for example)
Layout Issues
A good PC board is an essential part of RF circuit
design. The EV kit PC board can serve as a guide for
laying out a board using the MAX2745. Keep traces
carrying RF signals as short as possible to minimize
radiation and insertion loss. Use impedance control on
all RF signal traces. The VCC node on the PC board
should have decoupling capacitors to the closest
ground. Refer to the
Layout
section of the MAX2745
data sheet for more information.
_______________________________________________________________________________________
3
Evaluates: MAX2745
5
4
3
2
5
4
3
2
5
4
3
2
1
JP7
5
4
3
2
3
2
1
1
U1
1
NC
C19
39P
XTAL1
C33
GND
49
48
47
46
45
44
43
42
41
40
39
38
37
TEMPOUT
1
XTAL1
XTAL2
VDD_XOSC
PD_CHIP
VSS_CP
VDD_CP
CP_OUT
VSS_VCO
VCO_CTRL
VDD_VCO
TEMPOUT
SDATA
30K R83
30K R84
30K R85
MAX2745 Evaluation Kit
1
C6
100N
VDD
VDD
C59
5
4
3
2
GMCTRL_BPF
ODS
CFS
COE
5
4
3
2
12P
1
JP5
2
HEADER 2
1500pF
13
14
15
16
17
18
19
20
21
22
23
24
gnd
gnd
VRF IN
C10
100N
VDD
22P
22P
2
5
4
3
2
1
in
VCMOUT_1P
VCMOUT_1N
VDD
C11
R69
0
VDD
100N
C52
VS7006 Rev A
C98
TEST_EN
CKOUT
DOUT1
out
3
J34
SMA
R70
0
10P
C102
8.2nH
C12
100N
2
4
1.575GHz
SAFSE1G57AB0T00R00
TP5
1
R71
220 HEADER1
C60
1500pF
C9
100N
JP6
HEADER2
1
1pF
C7
100N
R27
0
1
C112
100N
IEXT_LNA
VCMOUT_1N
C47
C113
100N
1
2
3
4
5
6
7
8
9
10
11
12
R12
30K R86
VDD
VDD_AGC
PSAVE
XTAL_LFS
XTAL_SEL
BST_CTRL_AH
TEST_EN
VDD1V8_1
CKOUT
DOUT1
VT_CSW
VB_CSW
VOUT
30K R79
30K R80
30K R81
30K R82
TI_IP
0
5
4
3
2
R77
10K R14
10K R15
10K R16
Open
J36
SMA
5
4
3
2
5
4
3
2
TI_IN
VDD
R19
R20
3
JP8
2
1
HEADER 3
VDD18
22P
22P
1
0
0
C49
HEADER 3
C43
C36
R18
0
3
JP10
2
1
C110
100N
1
J28
SMA
CKOUT
C111
100N
1
J26
SMA
DOUT1
SDATAW
SDATA
SCLKW
SCLK
TESTENW
TESTEN
1
A1
2
1Y
3
2A
4
2Y
5
3A
6
3Y
VCC
14
6A
13
6Y
12
5A
11
5Y
10
4A
9
7
GND
74LV07A
4Y
8
10K
100N
U12
R17
5
4
3
2
5
4
3
2
5
4
3
2
Figure 1. MAX2745 EV Kit Schematic
C27
1
Open
SMA
J19
4
TO_QN
Open
C28
1
Open
SMA
J20
VINDC
VDDLDO
OUT
5
BP
4
10nF
C107
C105
1.0uF
TO_QP
C106
1.0uF
2
GND
3
SHDN/
MAX8510EXK2T
Open
U4
1
IN
TO USE CRYSTAL, DNP U1, POPULATE Y1
C29
1
Open
SMA
J21
TO USE TCXO, DNP Y1, POPULATE U1
HEADER1
TP1
VCO_CTRL
C81
6800pF
JP9
HEADER 3
R8
820
1
R6
0
C30
R5
820
Open
SMA
J22
1
2
JP2
HEADER 2
2
1
HEADER 2
VDD5V
1
2
HEADER 2
JP12
VDD
3
2
1
VDD
Open
1
TP2
TEMPOUT
R62
22.1K
HEADER1
C80
4700P
39P
Y1
16.368MHZ
C13
100N
C14
100N
VDD
C15
100N
HEADER1 HEADER1
TP3
TP4
2.7nH
C18
L60
VDD VDD
1500pF
C8
220P
C4
220P
JP4
VDDLDO
C16
HEADER 3
HEADER 2
HEADER 2
Open
TO_IN
1
2
3
1
2
1
2
JP11
VINDC
JP3
VDD18
JP1
TO USE 16.368 MHz CRYSTAL, DNP L60, C80
TO USE 32.736 MHz CRYSTAL,
POPULATE L60, C80
HEADER 3
TO_IP
VDD
C1
100N
C2
100P
VDD
4
2
GND OUT
3
16.367667MHz TCXO
C5
CLK
R59
XTAL1
1000pF
Open
C32
100P
R10
R11
200
200
100N
DIP SW4
C114
R13
200
GMCTRL_BPF
ODS
CFS
COE
1
2
3
4
8
7
6
5
200
S2
C22
100N
R9
C23 100K
100P
R1
70K
100N
U3
VDD
J24
SMA
VDD
C66
F5
C101
L58
C3
100N
C17
100N
VDD
XRES
CAP_BIAS
VDD_BIAS
VDD_LNAM
VSS
VSS
RF_IN
VSS
VDD_FUSE
IEXT_LNA
VDD_LPF
AGC_FIL
GMCTRL_BPF
ODS
CFS
COE
VDD_DIV
SCLK_SCL
GBVSS_ADC_DIV
VCMOUT_1P
VCMPOUT_1N
VDD_ADC
DVSS_ADC
DVDD_ADC
J33
SMA
1
36
35
34
33
32
31
30
29
28
27
26
25
VCMOUT_1P
1.0uF
Open
J35
SMA
VDD
C100
6800pF
C53
VDD
1
C48
VDD5V
VDD5V
C54
100N
R22 Open
Open
R23 Open
Open
PSAVE
XTAL_LFS
XTAL_SEL
BST_CTRL_AH
SDATAR
SCLKR
VDD
8
7
6
5
Open
J38
SMA
TI_QN
1
C50
R24 Open
Open
1
2
3
4
S3
C109
DIP SW4
100N
J5
Open
J37
SMA
TI_QP
1
C51
27
25
24
23
SDATAW
22
21
20
19
18
17
16
15
SCLKW
TESTENW
SCLKR
14
CONN DSUB 25-R
26
13
13 27
12
12 25
11
11 24
10
10 23
9
9 22
8
8 21
7
7 20
6
6 19
5
5 18
4
4 17
3
3 16
2
2 15
1
1 14
26
_______________________________________________________________________________________
R25 Open
Open
MAX2745 Evaluation Kit
Evaluates: MAX2745
1.0"
1.0"
Figure 2. MAX2745 EV Kit Component Placement Guide—
Component Side
Figure 3. MAX2745 EV Kit PC Board Layout—Layer 2
1.0"
1.0"
Figure 4. MAX2745 EV Kit PC Board Layout—Layer 3
Figure 5. MAX2745 EV Kit PC Board Layout—Component Side
5
_______________________________________________________________________________________
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