MAX31723PMB1 Peripheral Module

19-6332; Rev 0; 5/12
MAX31723PMB1 Peripheral Module
General Description
The MAX31723PMB1 peripheral module provides the
necessary hardware to interface the MAX31723 digital
thermometer and thermostat to any system that utilizes
PmodK-compatible expansion ports configurable for SPI
and/or GPIO communication. The IC provides temperature-to-digital conversion with no additional components.
Temperature readings are communicated from the device
over an SPI interface or a 3-wire serial interface. The
choice of interface is selectable by the user. For applications that require greater temperature resolution, the
user can adjust the readout resolution from 9 bits to 12
bits. This is particularly useful in applications where thermal runaway conditions must be detected quickly. The
thermostat has a dedicated open-drain output (TOUT).
Two thermostat operating modes (comparator and interrupt) control thermostat operation based on user-defined
nonvolatile trip points (THIGH and TLOW).
Refer to the MAX31723 IC data sheet for detailed information regarding operation of the IC.
Features
S Measures Temperatures from -55NC to +125NC
S Thermometer Accuracy is Q0.5NC
S Thermometer Resolution is Configurable from
9 Bits to 12 Bits
S Thermostat Output with User-Defined Nonvolatile
Thresholds
S SPI or 3-Wire Interface Selectable through
Jumpers
S 6-Pin Pmod-Compatible Connector (SPI/GPIO)
S Example Software Written in C for Portability
S RoHS Compliant
S Proven PCB Layout
S Fully Assembled and Tested
Ordering Information appears at end of data sheet.
MAX31723PMB1 Peripheral Module
Pmod is a trademark of Digilent Inc.
__________________________________________________________________ Maxim Integrated Products 1
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.
MAX31723PMB1 Peripheral Module
Component List
DESIGNATION
C1
DESCRIPTION
DESIGNATION
QTY
0.1FF Q10%, 16V X7R ceramic
capacitor (0603)
Murata GRM188R71C104KA01D
R1–R4
4
150I Q5% resistors (0603)
R5
1
4.7kI Q5% resistor (0603)
R6
1
10kI Q5% resistor (0603)
QTY
1
DESCRIPTION
C2
1
1FF Q10%, 10V X7R ceramic
capacitor (0603)
TDK C1608X7R1A105K
U1
1
Digital thermometer and
thermostat (8 FMAXM)
Maxim MAX31723MUA+
J1
1
6-pin right-angle male header
—
3
Shorting jumpers
1
10-pin (2 x 5) straight male
header
—
1
PCB: EPCB31723PM1
JP1
Component Suppliers
SUPPLIER
PHONE
WEBSITE
Murata Electronics North America, Inc.
770-436-1300
www.murata-northamerica.com
TDK Corp.
847-803-6100
www.component.tdk.com
Note: Indicate that you are using the MAX31723PMB1 when contacting these component suppliers
Detailed Description
SPI/3-Wire Interface
The MAX31723PMB1 peripheral module can plug directly
into a Pmod-compatible port (configured for SPI/3-wire)
through connector J1. For information on SPI and 3-wire
protocols, refer to the MAX31723 IC data sheet. The user
selects between SPI and 3-wire communication protocols
by setting the correct jumper configuration on JP2. See
Figure 1 for proper jumper settings.
Connector J1 provides connection of the module to the
Pmod host. The pin functions and pin assignments adhere
to the Pmod standard recommended by Digilent. Note that
when this module is operating in 3-wire mode, the hostside interface must be configured as GPIO to allow for bitbanged communication. 3-wire mode has the advantage
of freeing up an interface pin on the IC to allow for connection to the thermostat/alarm output. See Table 1.
The JP1 jumper block is used to configure the communication mode with the host board. The peripheral module
can communicate in either SPI or 3-wire mode. The correct shunt settings are shown in Table 2 and Figure 1.
Table 1. Connector J1
(SPI/3-Wire Communication)
PIN
SIGNAL
DESCRIPTION
1
SS
Chip enable. Must be asserted high for
communication to take place for either
the SPI or 3-wire interface.
MOSI
When SPI communication is selected,
this pin is the serial-data input for the
IC. When 3-wire communication is
selected, this pin carries bidirectional
data between the host and the IC.
3
MISO
When SPI communication is selected,
this pin is the serial-data output for
the IC. When 3-wire communication is
selected, this pin carries the IC TOUT
signal.
4
SCK
Serial clock. Used to synchronize data
movement on the serial interface for
either the SPI or 3-wire interface.
5
GND
Ground
6
VCC
Power supply
2
µMAX is a registered trademark of Maxim Integrated Products,
Inc.
__________________________________________________________________ Maxim Integrated Products 2
MAX31723PMB1 Peripheral Module
Table 2. Connector JP1 (Serial-Bus
Type Selection)
SHUNT
SPI MODE
3-WIRE MODE
1
3-5
1-2
2
4-6
3-5
3
9-10
4-6
Software and FPGA Code
Example software and drivers are available that execute
directly without modification on several FPGA development boards that support an integrated or synthesized microprocessor. These boards include the Digilent
Nexys 3, Avnet LX9, and Avnet ZEDBoard, although
other platforms can be added over time. Maxim provides
complete Xilinx ISE projects containing HDL, Platform
Studio, and SDK projects. In addition, a synthesized bit
stream, ready for FPGA download, is provided for the
demonstration application.
The software project (for the SDK) contains several
source files intended to accelerate customer evaluation and design. These include a base application
(maximModules.c) that demonstrates module functionality and uses an API interface (maximDeviceSpecific
Utilities.c) to set and access Maxim device functions
within a specific module.
The source code is written in standard ANSI C format, and
all API documentation including theory/operation, register
description, and function prototypes are documented in
the API interface file (maximDeviceSpecificUtilities.h & .c).
SPI MODE
3-WIRE MODE
The complete software kit is available for download at
www.maxim-ic.com. Quick start instructions are also
available as a separate document.
Figure 1. JP1 Jumper Settings
__________________________________________________________________ Maxim Integrated Products 3
MAX31723PMB1 Peripheral Module
VCC
R5
4.7k
J1
1
2
3
4
5
6
R1
R2
R3
R4
150
150
150
150
U1
1
TOUT
2
SS
MOSI
MISO
SCK
GND
VCC
3
GND
4
MAX31723
TOUT
VDD
CE
SERMODE
SCLK
SDI
GND
SDO
8
VCC
7
SERMODE
6
SDI
5
SDO
R6
10k
GND
C2
1uF
C1
VCC
GND
0.1uF
GND
JP2
SDI
MOSI
SDO
SERMODE
1
3
5
7
9
2
4
6
8
10
SDO
MISO
VCC
TOUT
MOSI
SDI
MOSI
SDI
MISO
SDO
MISO
SDO
TOUT
TOUT
no connect
SERMODE
Programming header - sets up either SPI
mode or 3-Wire mode (see diagram to the right)
VCC
SPI mode
SERMODE
GND
3-Wire mode
Figure 2. MAX31723PMB1 Peripheral Module Schematic
Figure 3. MAX31723PMB1 Peripheral Module Component Placement Guide—Component Side
__________________________________________________________________ Maxim Integrated Products 4
MAX31723PMB1 Peripheral Module
Figure 4. MAX31723PMB1 Peripheral Module PCB Layout—Component Side
Figure 5. MAX31723PMB1 Peripheral Module PCB Layout—Inner Layer 1 (Ground)
Figure 6. MAX31723PMB1 Peripheral Module PCB Layout—Inner Layer 2 (Power)
__________________________________________________________________ Maxim Integrated Products 5
MAX31723PMB1 Peripheral Module
Figure 7. MAX31723PMB1 Peripheral Module PCB Layout—Solder Side
Figure 8. MAX31723PMB1 Peripheral Module Component Placement Guide—Solder Side
__________________________________________________________________ Maxim Integrated Products 6
MAX31723PMB1 Peripheral Module
Ordering Information
PART
TYPE
MAX31723PMB1#
Peripheral Module
#Denotes RoHS compliant.
__________________________________________________________________ Maxim Integrated Products 7
MAX31723PMB1 Peripheral Module
Revision History
REVISION
NUMBER
REVISION
DATE
0
5/12
DESCRIPTION
Initial release
PAGES
CHANGED
—
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
© 2012
Maxim Integrated Products 8
Maxim is a registered trademark of Maxim Integrated Products, Inc.