MAXIM MAX13485EEVKIT+

19-4380; Rev 0; 12/08
MAX13485E Evaluation Kit
The MAX13485E evaluation kit (EV kit) provides a
proven design to evaluate the MAX13485E half-duplex
RS-485/RS-422 transceivers in an 8-pin µDFN package.
The MAX13485E EV kit PCB comes with a
MAX13485EELA+ installed. Contact the factory for free
samples of the pin-compatible MAX13486EELA+ to
evaluate this device.
Features
♦ Lead(Pb)-Free and RoHS Compliant
♦ Proven PCB Layout
♦ Fully Assembled and Tested
Component List
DESIGNATION QTY
Ordering Information
PART
TYPE
MAX13485EEVKIT+
EV Kit
DESCRIPTION
C1
1
0.1µF ±10%, 16V X7R ceramic
capacitor (0603)
TDK C1608X7R1C104K
C2
1
1µF ±20%, 10V X5R ceramic
capacitor (0603)
TDK C1608X5R1A105M
+Denotes lead(Pb)-free and RoHS compliant.
Quick Start
Required Equipment
J1
1
2-position terminal block
JU1, JU2, JU3
3
2-pin headers
R1
1
120Ω ±5% resistor (1206)
Before beginning, the following equipment is needed:
•
MAX13485E EV kit
R2, R3, R4, R5
4
Not installed, resistors (0603)
•
5V DC power supply
TP1, TP2
2
Not installed, test points
•
Two digital voltmeters
1
RS-485 half-duplex transceiver
(8 µDFN)
Maxim MAX13485EELA+
U1
—
3
Shunts
—
1
PCB: MAX13485E Evaluation Kit+
Component Supplier
SUPPLIER
TDK Corp.
PHONE
WEBSITE
847-803-6100
www.component.tdk.com
Note: Indicate that you are using the MAX13485E when contacting
this component supplier.
Procedure
The MAX13485E EV kit is fully assembled and tested.
Follow the steps below to verify board operation:
1) Verify that the jumpers are in their default position,
as shown in Table 1. JU1 connects the 120Ω load
resistor between A and B.
2)
For testing purposes, remove the shunt from JU1.
3)
Connect the positive terminal of the 5V supply to
VCC and the negative terminal of the supply to GND.
4)
Apply 5V on the RE and DE pads. This is a logic to
RS-485 DC test.
5)
Apply 5V on the DI pad and check that A-B is positive.
6)
Apply 0V on the DI pad and check that B-A is positive.
7)
Apply 0V on RE and DE. Apply 5V on A and 0V on B.
This is an RS-485 to logic DC test.
8)
Check the state of RO using a voltmeter. RO should
be approximately 5V.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
Evaluates: MAX13485E/MAX13486E
General Description
Evaluates: MAX13485E/MAX13486E
MAX13485E Evaluation Kit
Table 1. Jumper Table (JU1, JU2, JU3)
JUMPER
SHUNT
POSITION
JU1
JU2
JU3
Open
Closed*
DESCRIPTION
Does not connect the 120Ω resistor differentially between A and B
Connects the 120Ω resistor differentially between A and B
Open*
R2 and R5 not connected
Closed
Connects A and B through R2 and R5 if populated for testing custom termination and common-mode
Open
Closed*
Keeps DE and RE electrically separate
Shorts DE and RE
*Default position.
Detailed Description of Hardware
The MAX13485E EV kit provides a proven layout for the
MAX13485E. On-board pads are included for adding
external fail-safe resistors. JU2 can be used to monitor
the A and B lines with a differential probe. A terminal
block is also included to easily connect a cable to the EV
kit board.
An electrical grid with vias and GND vias are present on
the board to enable prototyping.
2
_______________________________________________________________________________________
MAX13485E Evaluation Kit
Evaluates: MAX13485E/MAX13486E
Figure 1. MAX13485E EV Kit Schematic
_______________________________________________________________________________________
3
Evaluates: MAX13485E/MAX13486E
MAX13485E Evaluation Kit
Figure 2. MAX13485E EV Kit Component Placement Guide—
Component Side
4
Figure 3. MAX13485E EV Kit PCB Layout—Component Side
_______________________________________________________________________________________
MAX13485E Evaluation Kit
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 5
© 2008 Maxim Integrated Products
SPRINGER
is a registered trademark of Maxim Integrated Products, Inc.
Evaluates: MAX13485E/MAX13486E
Figure 4. MAX13485E EV Kit PCB Layout—Solder Side