max31785 evaluation kit evaluates: max31785

MAX31785 Evaluation Kit Evaluates: MAX31785

General DescriptionThe MAX31785 evaluation kit (EV kit) provides the hardware and software graphical user interface (GUI) necessary to evaluate the MAX31785 6-channel intelli-gent fan controller. The EV kit includes a MAX31785ETL+ installed, as well as a 12V fan and USB-to-I2C module to communicate with the PC.

EV Kit Contents AssembledcircuitboardincludingMAX31785ETL+ DS3900module 12Vfan Mini-USBcable

Features EasyEvaluationoftheMAX31785 USBHIDinterface WindowsXP®-andWindows®7-Compatible

Software RoHSCompliant ProvenPCBLayout FullyAssembledandTested

19-6535; Rev 0; 12/12

Ordering Information appears at end of data sheet.

EV Kit Photo

Windows and Windows XP are registered trademarks and registered service marks of Microsoft Corporation.

Maxim Integrated 2


www.maximintegrated.com

Component List

*EP = Exposed pad.

DESIGNATION QTY DESCRIPTIONB1 1 Yellowbananajack

B2, B4 2 Blackbananajacks

B3 1 Redbananajack

C001,C101,C201,C301,C401,C501 6 2.2nF,X7Rceramic

capacitors(0805)

C004,C1,C2,C8,C11, C12, C15, C21 c8 100nF,X7Rceramic

capacitors(0805)

C002,C003,C102,C103,C202,C203,C302,C303,C402,C403,C502,C503

0 Donotpopulate,ceramiccapacitors(0805)

C3,C5,C10,C16,C18,C20 6 10nF,X7Rceramiccapacitors

(0805)

C4,C6,C17,C19 4 1µF,X7Rceramiccapacitors(0805)

C7, C13 2 10µF,X7Rceramiccapacitors(0805)

C9 1 47µFtantalumcapacitor(Case C)

C14 0 Donotpopulate,tantalumcapacitor (Case C)

D1,D2 2 RedLEDs(1206)

J1,P001,P1, P101,P201,P301,

P401,P5018 2-pin headers, 2.54mm pitch

P002C,P002O,P102,P202,P302,

P402,P5027 4-pin headers, 2.54mm pitch

Q001,Q101,Q201,Q301,Q401,Q501 6 npntransistors(3SOT23)

FairchildMMBT3904

R001,R002, R16–R21,R101,R102,R201,R202,R301,R302,R401,R402,R501,R502

18 0Ω±1%resistors(0805)

R003,R006,R103,R106,R203,R206,R303,R306,R403,R406,R503,R506

12 10Ω±1%resistors(0805)

R004,R6,R7,R22,R104,R204,R304,

R404,R5040 Donotpopulate,resistors

(0805)

DESIGNATION QTY DESCRIPTION

R005C,R005O,R105,R205,R305,

R405,R5057 1kΩ±1%resistors(0805)

R007,R4,R5,R8,R11–R15,R107,R207,R307, R407,R507

14 4.7kΩ±1%resistors(0805)

R1–R3,R23,R24 5 100kΩ±1%resistors(0805)

R9,R10 2 1.2kΩ±1%resistors(0805)

S1 1 Single-polepushbuttonswitch

TP001–TP004,TP1–TP9,

TP101–TP104,TP201–TP204,TP301–TP304,TP401–TP404,TP501–TP504

33 Whitetestpoints

TP13, TP27 2 Redtestpoints

TP14–TP21,TP23,TP24, TP26 11 Black test points

TP25 1 Yellow test point

U1A 16-channel intelligent fan controller(40TQFN-EP*)Maxim MAX31785ETL+

U1B 0

Notinstalled,6-channelintelligent fan controller (40TQFN-EP*)Maxim MAX31785ETL+

U001 1Low-voltage, single-supply, SPDTswitch(6SC706)MaximMAX4599EXT-T

U2 1 USB communications moduleMaximDS3900

U3 1Digitaltemperaturesensor (8SO,150mil)MaximDS75LVS+

— 1 PCB: MAX31785 EV KIT

Maxim Integrated 3



MAX31785 EV Kit Files

Quick StartRequired Equipment MAX31785EVkit WindowsXPorWindows7PC USBport Mini-USBcable(included) EVkithardware(included) 12Vfan(included) 3.3V(100mA)DCpowersupply 12V(500mA)DCpowersupply(ifonlyoperatingthe

one provided fan)Note: In the following sections, software-related items are identifiedbybolding.Textinboldreferstoitemsdirectlyfrom the install or EV kit software. Text in bold and underlinedreferstoitemsfromtheWindowsoperatingsystem.

ProcedureTheEVkitisfullyassembledandtested.Followthestepsbelowtoverifyboardoperation:1) EnsurethatjumperJ1ispopulatedandtheDS3900

module (U2) is connected.2) Connect a 12V fan to one of the six channel fan

headers.Forthefansupplied,makesuretoconnectFANGNDtotheblackwireandVFANtotheredwire.

3) Set the EV kit hardware on a nonconductive surface to ensure that nothing on the PCB is shorted to the workspace.

4) Attach theGND first (black connector) to the groundjack of the 3.3V supply and connect the FANGND(blackconnector)tothegroundjackofthe+12Vsupply.

5) Connect the FANGND and GND nodes together.There isnotaconnectionbetween thesenodesonthe PCB.

6) Connect the +3.3V (red connector) and +12V (yellow connector) power supplies and turn the power on. Eithersupplycanbeturnedonfirst(nosequencingisrequired).

7) Prior to starting the GUI, connect the EV kit hardware toaPCusingthesuppliedmini-USBcable,orequiv-alent.TheCOMLED(D2)ontheDS3900shouldbered and slowly flash orange.

8) Windows should automatically begin installing thenecessary device driver. The USB interface of the EVkithardwareisconfiguredasanHIDdeviceandtherefore does not require a unique/custom devicedriver. Once the driver installation is complete, aWindows message appears near the System Iconmenu, indicating that the hardware is ready to use. DonotattempttoruntheGUIpriortothismessage.If you do, then you must close the application and restartitoncethedriverinstallationiscomplete.OnsomeversionsofWindows,administratorprivilegesmayberequiredtoinstalltheUSBdevice.

9) Once the device driver installation is complete,visit www.maximintegrated.com/evkitsoftware to download the latest version of the EV kit software, MAX31785EVKitSoftware.zip. Save the EV kit soft-ware to a temporary folder.

10) Afterthe.EXEfilehasbeenextractedfromtheZIP,double-click to launch the GUI. A message box stating The publisher could not be verified. Are you sure you want to run this software? may appear. If so, click Yes.

11) WhentheGUIappears,thetextatthebottomofthewindow should indicate that the USB is connected. The COM LED (D2) on the DS3900 changes togreen.TheGUI initiallysets theCONTROLpin lowtodisablethefan.

12) TheGUIcannowbeusedtoevaluatetheMAX31785.

Note: The .EXE file is downloaded as a .ZIP file.

FILE DESCRIPTIONMAX31785EVKSoftware.EXE Application program

Maxim Integrated 4



Detailed Description of SoftwareGeneral TabThe General tab sheet (Figure 1) displays the statusof all pages and can be read by pressing the Read Once button in theMonitor group box. Start Monitor continuously reads until Stop Monitor is pressed. The values can be displayed inHex or DIRECT format byselecting the appropriate radio button in the Select display section. The Commandsgroupboxallowsusersto read/write to registers that are 0–2 bytes long. First,select an item in the Select a Page drop-down list to write to PAGE (00h). Then, under theSelect or Enter Command drop-down list, either select the command in thedrop-downlistorenterthecommandbyteandpressthe Read button. To write to a register, enter the databyteintheDataeditboxandpressWrite. In the Global Commands groupbox,pressing theSoft Reset buttonresets thedevice by setting a bit inMFR_MODE (D1h)to 1, 0, and then 1 againwithin 8ms.TheHard Reset button resets the device by pulling theRST pin low for 10ms. The FanRunTime Reset, FanPwmAvg Reset, and MFRTimeCnt Reset buttons reset their values bywriting a sequence of all zeros, all ones, and all zeroswithin 8ms. The FanRunTime Reset and FanPwmAvg Reset only reset the MFR_FAN_RUN_TIME (7Fh) andMFR_FAN_PWM_AVG(F8h)valuesforthepageselectedfrom the Select a Page drop-down list. The Clear Faults button sends theCLEAR_FAULTS (03h) command andthe Read Fault Log button writes the fault log to a.TXT file. If the ALERT pin is asserted, an alert indicator appears next to the Alert Responsebuttonandnolongerresponds to its fixed slave address. The Alert Response buttonsendstheARA(19h),waitsforthedevicetoACK,and then reads the fixed slave address. The Set Control radio buttonspull theCONTROLpin either highor low.SettingtheCONTROLpinlowgloballyturnsallfansoff.

PMBusTM TabThe PMBus™ tab sheet (Figure 2) allows the user tochange the slave address and read/write to all PMBuscommands. To change the software slave address, enter the slave address in the Software Slave Address edit box and press the Change button. This only changesthe slave address that the software uses to communicate and does not change the hardware’s slave address. To search forallslaveaddressesavailableon the I2Cbus,press Find. Note: Slave address 34h is the factory- programmed address and should not be selected for communication.Toread/writetoaPMBuscommand,firstselect a page in the Select a Page drop-down list, which writestoPAGE(00h).Thenenterthecommandaddressin the Commandspinboxandselectthenumberofbytesto read/write from theNumber of Data drop-down list. Press Read or enter data in the edit boxes and pressWrite. To read/write more than 16 bytes, click on theWordradiobuttonintheModegroupbox,whichplacestwobytesineachdataboxforamaximumof32bytes.

File TabThe File tabsheet (Figure3) cansave thePMBusset-ting to a file and program the MAX31785 with settings saved in a file. The flashed-stored PMBus settings can besaved toa file in threedifferent formats.TheDump buttonsavesthesettingstoa.TXTfileinatab-delimitedtableformat.TheMachine Code Dumpbuttonsavesthecommands to a .TXT file in a machine-code format. The Intel Hex Dump button generates a .HEX file with theSTORE_DEFAULT_ALL (11h) command placed at theend of the file. To program the device with values saved in a file, press the Fill Devicebuttonandselecta.TXTfilethat was generated using the Dumpbutton.

PMBus is a trademark of SMIF, Inc.

Maxim Integrated 5



Figure 1. MAX31785 EV Kit GUI (General Tab)

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Figure 2. MAX31785 EV Kit GUI (PMBus Tab)

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Figure 3. MAX31785 EV Kit GUI (File Tab)

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Detailed Description of HardwareConnecting a FanMount the fan to the PCB with the provided mounting holes to prevent the fan from moving while spinning. To connect4-wirefans,connecttoFANGND,VFAN,TACHX,andPWMX.For3-wirefans,leavePWMXunconnected.FANGNDisatypicalblackwireandVFANisusuallyaredwire on a fan.

UserSupplied Remote Diode or Remote VoltageTo connect a user-supplied external remote diode or remotevoltage,removeresistorsRX01andRX02,whereXisthechannelnumber.Thenconnectthediodeorvolt-agetotheheaderlabeledwithRS+XandRS-X.

UserSupplied DS75LVTouseanoff-boarddigital temperature sensor, connecttheDS75LVdevice(U3)totheMSDA,MSCL,andGNDtest points or use the I2C master access header. The user-suppliedDS75LVaddresspinsshouldbeconfiguredfor temp sensor I2C1,2,or3.Theon-boardDS75LVisconfiguredtobetempsensorI2C0.

UserSupplied I2C InterfaceTo use the device with a user-supplied I2C interface, remove the DS3900 module from the EV kit. Then connectSDA,SCL,andGNDofthemicrocontrollertothetestpointsprovidedontheEVkitboard.

TroubleshootingAll efforts were made to ensure that each EV kit works on thefirsttry,rightout-of-the-box.Intherareoccasionthataproblemissuspected,seeTable2tohelptroubleshootthe issue.

Determine DS3900 Module TypeTheDS3900module has been updated to theDS3900HID(Figure4).IftheDS3900COM(Figure5)isattachedtotheEVkit,downloadtheMAX31785EVKitCOM.ZIPfileavailableatwww.maximintegrated.com/evkitsoftware and follow the Quick Start GuideincludedintheZIPfile.

Table 1. Description of LEDsLED COLOR DESCRIPTION

D1 Red ALERT:Afaultoccurred.Thedevicenolongerrespondstoitsfixedslaveaddress. See the Generaltab(Figure1)toclear.

D2 Red FAULT: A fault occurred. See the Generaltabtoclear.DS3900

D1 Red USB Power Fault: A fault occurred due to overvoltage limit, current limit, or thermal limit.

DS3900D2

Red Communication:Afterthesoftwarehasinitializedthehardware,theLEDflashesredwhenacommand from the PC is received.

Green Initialized:Hardwarehasbeeninitializedbysoftware.

http://www.maximintegrated.com/evkitsoftware

Maxim Integrated 9



Table 2. TroubleshootingSYMPTOM CHECK SOLUTION

GUI indicates USB not Connected

DS3900HIDmoduleTheDS3900modulehasbeenupdated.GotoDetermine DS3900 module Type to see if the correct one is connected.

IstheLEDlabeledD1ontheDS3900red?

If yes, then the electronic fuse is in a fault state. Inspect for electrical shorts on the PCB and make sure that the PCB is not sitting on a conductive surface.

DoestheLEDlabeledD2ontheDS3900turngreenwhentheGUIisrunning?

If not, then exit the GUI and try running it again. If the LEDstilldoesnotturngreen,thenexittheGUIandtryconnectingtheUSBcabletoadifferentUSBportonthePCandwaitforaWindowsmessagethatindicatesthatthehardwareisreadytouse.RuntheGUIagain.

AreanyoftheLEDsilluminated?Ifnot,thenthePCBmaynotbegettingpower.Makesure3.3VisconnectedtotheredbananajackandtheUSBcableisconnectedtoaPC.

GUI indicates Could not communicate with

PMBus. Slave address not recognized.

J1 MakesureJ1ispopulatedwithajumper.

MAX31785 Make sure there is a MAX31785 in the socket or solder to theboard.

Fanwillnotturnon

VFAN Makesurethereis12Vconnectedtotheyellowbananajackifusingthesuppliedfan.

FanheaderMake sure the fan is properly connected to the fan header. FANGNDisablackwireandVFANisaredwireonthefansupplied.

CONTROLpin MakesuretheCONTROLpinishighbyclickingontheHighradiobuttonontheGeneraltab.

FAN_CONFIG_1_2(3Ah) CheckthattheFanEnablebit(bit7)inFAN_CONFIG_1_2is set to 1.

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Figure 4. DS3900 HID Module Figure 5. DS3900 COM Module

Maxim Integrated 11



Figure 6a. MAX31785 EV Kit Schematic (Sheet 1 of 3)

P11

P22

P33

MCL

R4

GN

D5

P46

P57

GN

D8

P69

P710

P811

P912

VCC

13G

ND

14P1

0/SC

L15

P11/

SDA

16U

2

DS3

900

C7 10uF

C8 100n

F

B4 GN

D B

AN

AN

A

B33.

3V B

AN

AN

AC1

310

uFC1

210

0nF

C11

100n

FC1

010

nFG

ND

R502

0

R501

0

C501

2.2n

F

11

22

33

44

P502

40M

M F

AN

R507

4.7k

C503

DN

P

R506

10

R504

DN

PC5

02D

NP

R503

10

R505

1k

3.3V

C6 1uF

C5 10nF

C4 1uF

C3 10nF

3.3V

R16

0R1

70

R18

0

R19

0

R20

0

R21

0

R22

DN

P

R15

4.7k

R14

4.7k

R13

4.7k

R12

4.7k

R11

4.7k

R6 DN

P

R7 DN

P

R8 4.7k

R9 1.2k

R10

1.2k

D1

FAU

LTD2

AL

ERT

12

S1 RESE

TC2 10

0nF

R23

100k

R24

100k 3.

3V

R5 4.7k

R4 4.7k

3.3V

MSD

A

MSC

L

SDA

SCL

RST

AL

ERT

FAU

LT

CON

TRO

LTA

CHSE

LA

0

REG

18

REG

25

TACH

0PW

M0

RS+0

RS-0

VSS

TACH

1PW

M1

RS+1

RS-1

TACH

2PW

M2

RS+2

RS-2

TACH

3PW

M3

RS+3

RS-3

TACH

4PW

M4

RS+4

RS-4

TACH

5PW

M5

RS+5

RS-5

SDA

1

SCL

2

O.S

.3

GN

D4

A2

5A

16

A0

7VC

C8

U3

DS7

5LV

R1 100k

R2 100k

R3 100k

3.3V

C1 100n

F

B1

+12/

24/4

8V B

AN

AN

A

FAN

GN

DC1

510

0nF

TP9

TACH

SEL

TACHSEL

TP8

CON

TRO

L

CONTROL

TP7

FAU

LT

FAULT

TP6

AL

ERT

ALERT

TP5

RST RST

TP4

SCL SCL

TP3

SDA SDA

TP30

1TA

CH3

TACH3

TP20

3RS

-2 RS-2

TP20

2PW

M2

PWM2

TP20

1TA

CH2

TACH2

TP10

4RS

+1 RS+1

TP10

3RS

-1 RS-1

TP10

2PW

M1

PWM1

TP10

1TA

CH1

TACH1

TP00

4RS

+0 RS+0

TP00

3RS

-0 RS-0

TP13

VDD VDD

TP50

4RS

+5 RS+5

TP50

3RS

-5 RS-5

TP50

2PW

M5

PWM5

TP50

1TA

CH5

TACH5

TP40

4RS

+4 RS+4

TP40

3RS

-4 RS-4

TP40

2PW

M4

PWM4

TP40

1TA

CH4

TACH4

TP30

4RS

+3 RS+3

TP2

MSC

L

MSCL

TP1

MSD

A

MSDA

TP00

2PW

M0

PWM0

TP00

1TA

CH0

TACH0

TP30

3RS

-3 RS-3

TP30

2PW

M3

PWM3

B2 FAN

GN

D B

AN

AN

A

TP24

GN

D GND

TP23

GN

D GND

TP21

GN

D GND

TP20

GN

D GND

TP19

GN

D GND

TP18

GN

D GND

TP17

GN

D GND

TP16

GN

D GND

TP15

GN

D GND

TP14

GN

D GND

1

23

Q50

1M

MBT

3904

MSD

A14

MSC

L15

SDA

31

SCL

32

RST

13

AL

ERT

38

FAU

LT

34

CON

TRO

L35

A1/

TACH

SEL

37

A0

33

REG

1822

REG

2529

VSS

36VS

S21

VSS

2

VDD

9

RS-5

39RS

+540

PWM

516

TACH

517

TACH

030

PWM

028

RS+0

6

RS-0

7

TACH

127

PWM

126

RS+1

8

RS-1

10

TACH

225

PWM

224

RS+2

11

RS-2

12

TACH

323

PWM

320

RS+3

5

RS-3

4

TACH

419

PWM

418

RS+4

3

RS-4

1

EP41

U1A

MA

X317

85

VFA

N

GN

D

GN

D

GN

D

GN

D

GN

D

GN

D

GN

D

GN

D

FAN

GN

DVF

AN

HTA

CH5

HP

WM

5

GN

D

500

MIL

TRA

CE

500

MIL

TRA

CE

MO

UN

T N

EAR

BOA

RD E

DG

E

TP20

4RS

+2 RS+2

1 2

P501

TEM

P D

IOD

E/VO

LTA

GE

SEN

SE H

EAD

ER

12

J1 VCC

JUM

PER

TP25

VFA

N+

C14

DN

P

12

P1 I2C

50 V

OLT

50VO

LT

SDA

SCL

RST

AL

ERT

FAU

LT

CON

TRO

L

TACH

SEL

(TA

NT

C-SM

T)

3.3V

VDD

TP26

FAN

GN

D

TP27

3.3V 3.3V

C9 47uF

Maxim Integrated 12



Figure 6b. MAX31785 EV Kit Schematic (Sheet 2 of 3)

1 2

P001

TEM

P D

IOD

E/VO

LTA

GE

SEN

SE H

EAD

ER

2 3 41

P002

O

FAN

HEA

DER

2 3 41

P002

C

FAN

HEA

DER

IN1

V+2

GN

D3

NC

4CO

M5

NO

6U

001

MA

X459

9

1

23

Q00

1M

MBT

3904

R001

0

R002

0

3.3V

C004

100n

F

3.3V

R005

O1k

3.3V

R005

C1k

R007

4.7k

R006

10C0

03D

NP

R004

DN

P

R003

10

C002

DN

P

VFA

NFA

NG

ND

RS+0

RS-0

TACH

SEL

TACH

0

PWM

0

1 2

P101

TEM

P D

IOD

E/VO

LTA

GE

SEN

SE H

EAD

ER

2 3 41

P102

FAN

HEA

DER

1

23

Q10

1M

MBT

3904

3.3V

R105

1k

R107

4.7k

R106

10C1

03D

NP

R104

DN

P

R103

10

C102

DN

P

VFA

NFA

NG

ND

RS+1

RS-1

TACH

1

PWM

1

C001 2.

2nF

GN

D

GN

D

GN

D

GN

D

GN

D

R101

0

R102

0

C101 2.

2nF

1 2

P201

TEM

P D

IOD

E/VO

LTA

GE

SEN

SE H

EAD

ER

2 3 41

P202

FAN

HEA

DER

1

23

Q20

1M

MBT

3904

3.3V

R205

1k

R207

4.7k

R206

10C2

03D

NP

R204

DN

P

R203

10

C202

DN

P

VFA

NFA

NG

ND

RS+2

RS-2

TACH

2

PWM

2

GN

D

GN

D

R201

0

R202

0

C201 2.

2nF

1 2

P301

TEM

P D

IOD

E/VO

LTA

GE

SEN

SE H

EAD

ER

2 3 41

P302

FAN

HEA

DER

1

23

Q30

1M

MBT

3904

3.3V

R305

1k

R307

4.7k

R306

10C3

03D

NP

R304

DN

P

R303

10

C302

DN

P

VFA

NFA

NG

ND

RS+3

RS-3

TACH

3

PWM

3

GN

D

GN

D

R301

0

R302

0

C301 2.

2nF

1 2

P401

TEM

P D

IOD

E/VO

LTA

GE

SEN

SE H

EAD

ER

2 3 41

P402

FAN

HEA

DER

1

23

Q40

1M

MBT

3904

3.3V

R405

1k

R407

4.7k

R406

10C4

03D

NP

R404

DN

P

R403

10

C402

DN

P

VFA

NFA

NG

ND

RS+4

RS-4

TACH

4

PWM

4

GN

D

GN

D

R401

0

R402

0

C401 2.

2nF

FAN

GN

DVF

AN

HTA

CH0O

HP

WM

0

FAN

GN

DVF

AN

HTA

CH0C

HP

WM

0

FAN

GN

DVF

AN

HTA

CH1

HP

WM

1

FAN

GN

DVF

AN

HTA

CH2

HP

WM

2

FAN

GN

DVF

AN

HTA

CH3

HP

WM

3

FAN

GN

DVF

AN

HTA

CH4

HP

WM

4

500

MIL

TRA

CE50

0 M

IL T

RACE

500

MIL

TRA

CE50

0 M

IL T

RACE

500

MIL

TRA

CE50

0 M

IL T

RACE

500

MIL

TRA

CE50

0 M

IL T

RACE

500

MIL

TRA

CE50

0 M

IL T

RACE

MO

UN

T N

EAR

BOA

RD E

DG

E

MO

UN

T N

EAR

BOA

RD E

DG

E

MO

UN

T N

EAR

BOA

RD E

DG

E

MO

UN

T N

EAR

BOA

RD E

DG

E

MO

UN

T N

EAR

BOA

RD E

DG

E

Maxim Integrated 13



Figure 6c. MAX31785 EV Kit Schematic (Sheet 3 of 3)

MSDAMSCL

SDASCLRSTAL ERTFAUL TCONTROLTACHSELA0

REG18S

REG25S

TACH0PWM0RS+0RS- 0

VDD

VSS

TACH1PWM1RS+1RS- 1

TACH2PWM2RS+2RS- 2

TACH3PWM3RS+3RS- 3

TACH4PWM4RS+4RS- 4

TACH5PWM5RS+5RS- 5

MSDA14

MSCL15

SDA31

SCL32

RST13

AL ERT38

FAUL T34

CONTROL35

A1/TACHSEL37

A033

REG1822

REG2529

VSS 36VSS 21VSS 2

VDD 9

RS- 5 39RS+5 40PWM5 16TACH5 17

TACH0 30

PWM0 28

RS+0 6

RS- 0 7

TACH1 27

PWM1 26

RS+1 8

RS- 1 10

TACH2 25

PWM2 24

RS+2 11

RS- 2 12

TACH3 23

PWM3 20

RS+3 5

RS- 3 4

TACH4 19

PWM4 18

RS+4 3

RS- 4 1

EP 41

U1B

MAX31785

C191uF

C1810nF

C171uF

C1610nF

GND

GNDC21100nF

C2010nF

Maxim Integrated 14



Figure 8. MAX31785 EV Kit PCB Layout—Bottom

Figure 7. MAX31785 EV Kit PCB Layout—Top

Maxim Integrated 15



#Denotes an RoHS-compliant device that may include lead(Pb), which is exempt under the RoHS requirements.

Ordering InformationPART TYPE

MAX31785K# EV Kit

Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.

Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. © 2012Maxim Integrated Products, Inc. 16


Revision HistoryREVISIONNUMBER

REVISION DATE DESCRIPTION PAGES

CHANGED0 12/12 Initial release —

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.

max31785 evaluation kit evaluates: max31785

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