Evaluates: MAX2745
MAX2745 Evaluation Kit
2
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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.
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.
• VDD5V (JP12) is the power supply for the I
2
C control
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.
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.
Component List (continued)
DESIGNATION
QTY
DESCRIPTION
L58
1
8.2nH
±
0.1nH (0402) inductor
Murata LQP15MN8N2B02
L60
0***
Open
±
0.1nH (0402) inductor
Murata
R1
1
70k
Ω
±
1% (0402), 1/16W resistor
R5, R8
2
820
Ω
±
1% (0402), 1/16W resistors
R6, R18, R19,
R20, R27, R69,
R70, R77
8
0
Ω
±
1% (0402), 1/16W resistors
R9
1
100k
Ω
±
1% (0402), 1/16W resistor
R10–R13
4
200
Ω
±
1% (0402), 1/16W resistors
R14–R17
4
10k
Ω
±
1% (0402), 1/16W resistors
R22–R25
0**
Open,
±
1%, 1/16W resistors
R59
0***
Open,
±
1% (0402), 1/16W resistor
R62
1
22.1k
Ω
±
1% (0402), 1/16W resistor
R71
1
220
Ω
±
5% (0402), 1/10W resistor
R79–R86
8
30k
Ω
±
1% (0402), 1/16W resistors
DESIGNATION
QTY
DESCRIPTION
S2, S3
2
DIP switches SW4 SMT
CTS 204-12ST
TP1–TP5
5
Test points, PC mini, 0.040 red
Digi-key 5000K-ND
U1
0***
Open TXCO, 16.367667MHz, SM
Rakon
U3
1
MAX2745ECM IC, GPS RF, SM
Maxim MAX2745ECM
U4
1
MAX8510EXK27 low-noise linear
regulator
Maxim MAX8510EXK27
U12
1
Hex buffer/driver with open drain
Texas Instruments SN74LV07ADR
Y1
1
16.368327MHZ XTL
Rakon IDD30UM-1SJ
16.367MHz/XZB548
**
These components are for internal test purposes.
***
These are the optional components. See the instructions on the schematic for more details.