PART QTY DESCRIPTION

MAX5954LEVKIT 1 MAX5954L evaluation kit

CMAXQUSB 1 SMBus interface board

PART*IC

PACKAGE

SMBusINTERFACE

TYPE

MAX5954LEVKIT 36 TQFN-EP** Not included

MAX5954LEVCMAXQUSB 36 TQFN-EP** CMAXQUSB

Component List

MAX5954LEVCMAXQUSB(MAX5954L EV System)

Ordering Information

Note: The MAX5954L EV kit software is provided with theMAX5954LEVKIT. However, the CMAXQUSB interface board isrequired to interface the EV kit to a computer when using thesoftware.

*Temp range is 0°C to +70°C for all parts.**EP = Exposed paddle.

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MAX5954L Evaluation Kit/Evaluation System

________________________________________________________________ Maxim Integrated Products 1

19-3907; Rev 0; 11/05

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.

General DescriptionThe MAX5954L evaluation kit (EV kit) is a fully assem-bled and tested surface-mount single hot-plug con-troller PC board for a single PCI Express™ hot-plugslot. The circuit uses a MAX5954L IC in a 36-pin thinQFN package. The EV kit provides independent powercontrol for the 12V, 3.3V, and 3.3V-auxiliary outputs of asingle PCI-Express x16 connector. The EV kit demon-strates the MAX5954L IC’s inrush current control,output overcurrent/short-circuit protection and inputundervoltage monitoring features.

The MAX5954L IC controls two separate externaln-channel MOSFETs for the 12V and 3.3V outputs,respectively. Additionally, the MAX5954L has an inter-nal MOSFET that controls the 3.3V-auxiliary output.Switches are provided to independently enable/disablethe 12V/3.3V main and 3.3V-auxiliary supplies.

The MAX5954L EV kit can be reconfigured for evaluat-ing a x1, x4, or x8 PCI Express single hot-plug design.Alternatively, the EV kit can also be used to demon-strate the MAX5954L hot-plug features without usingthe PCI Express x16 connector.

The EV kit includes a MAX7313 I/O expander thatenables communication through an SMBus™ interfacefor the MAX5954L signals and some of the PCI Expresssignals. A CMAXQUSB interface board can be used toenable PC communication through the SMBus inter-face. Windows® 98-/2000-/XP-compatible GUI softwareis provided to access the MAX7313 I/O expander andMAX5954L signals. The MAX5954L EV kit can also beused in local control, without any software, or interfacedto a user-provided SMBus system signal.

Order the MAX5954LEVCMAXQUSB for a complete PC-based evaluation of the MAX5954L. Order theMAX5954LEVKIT if you already have a CMAXQUSBinterface board or do not require PC-based evaluationof the MAX5954L.

Features♦ Demonstrate PCI Express x16 Single Hot-Plug

Design

♦ Independent Output Controls

12V and Up to 5.5A (Adjustable)

3.3V and Up to 3A (Adjustable)

3.3V-Aux and Up to 0.375A

♦ Evaluate Hot-Plugging PCI Express x1, x4, x8, orx16 Line Cards

♦ Demonstrate Input Inrush Current Control

♦ Demonstrate Output Overcurrent/Short-CircuitProtection

♦ Monitor Input Undervoltage for 12V, 3.3V, and3.3V-Aux with Status Reports

♦ Configurable Power-On Reset (POR)

♦ Independent On/Off Controls for 12V/3.3V

♦ Independent 3.3V-Aux Output with SeparateOn/Off Control

♦ Latched Output After Fault Conditions (12V, 3.3V,3.3V-Aux)

♦ Input/Output Interface Using a MAX7313 I/OExpander (SMBus Interface) or Local Control

♦ Can be Controlled Locally without Software

♦ Windows 98-/2000-/XP-Compatible Software

♦ Surface-Mount Components

♦ Fully Assembled and Tested

PCI Express is a trademark of PCI-SIG Corp.SMBus is a trademark of Intel Corp.Windows is a registered trademark of Microsoft Corp.

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MAX5954L Evaluation Kit/Evaluation System

2 _______________________________________________________________________________________

DESIGNATION QTY DESCRIPTION

C1 11500µF, 16V electrolytic capacitor(12.5mm x 13.5mm case)Panasonic EEVFK1C152Q

C2 1

3300µF, 6.3V, low-impedanceelectrolytic capacitor (12.5mm x13.5mm case)Sanyo 6.3CV3300KX

C3, C4, C5 310µF ±20%, 25V X7R ceramiccapacitors (1812)TDK 4532X7R1E106M

C6–C9 41µF ±10%, 16V X7R ceramiccapacitors (0805)Murata GRM21BR71C105K

C11, C12 20.1µF ±10%, 16V X7R ceramiccapacitors (0603)Murata GRM188R71C104K

C13, C14 0Not installed ceramic capacitors(0805)

D1 11A, 40V Schottky diode (SOD-123)Diodes Incorporated 1N5819HW-F

D2, D3, D5, D6 4 Green surface-mount LEDs (1206)

D4 1 Yellow surface-mount LED (1206)

J1 1PCI Express x16 connectorMolex 87715-3305

J2 1 9-pin header

J4 1 2 x 10 right-angle female receptacle

JU1, JU2 2 2-pin headers

JU3, JU4 2 3-pin headers

N1, N2 220V, 13.4A n-channel MOSFETs(SO-8)Vishay Si7448DP-T1

R1 1

0.008Ω ±2%, 0.5W sense resistor(2010)IRC LRC-LRF2010-01-R008-G orVishay WSL20108L000F

DESIGNATION QTY DESCRIPTION

R2 1 750Ω ±1% resistor (1210)

R3 1 1kΩ ±5% resistor (1206)

R4, R10, R11,R12, R17, R20,

R21, R220 Not installed resistors (0805)

R5, R8, R18,R19, R23, R24,

R257 10kΩ ±5% resistors (0603)

R6, R7 2 51kΩ ±5% resistors (0603)

R9 1 3.3kΩ ±5% resistor (0603)

R13, R14, R16,R28

4 150Ω ±5% resistors (0603)

R15 10.005Ω ±1%, 0.5W sense resistor(2010)Vishay WSL20105L000FTA

SW1 1 SPST momentary-contact switch

SW2, SW3 2 SPDT slide switches

VIN1, VIN2,VIN3, GND,

GND5 Uninsulated banana jacks

TP1, TP2, TP3,TP13, TP15,TP16, TP18,TP19, TP20

9 PC test points, red

TP4–TP12 9 PC test points, black

TP14, TP17 2 PC test points, miniature, red

U1 1MAX5954LETX (6mm x 6mm, 36-pinTQFN)

U2 116-port I/O expander (4mm x 4mm,24-pin TQFN)MAX7313ATG

— 4 Shunts (JU1–JU4)

— 1 MAX5954L EV kit PC board

— 2 Rubber bumpers

MAX5954LEVKIT Component List

Quick StartRequired equipment

• One each of the following DC power supplies

12V, 7A

3.3V, 5A

• Three voltmeters

The 3.3V power supply can be used to power the main3.3V and 3.3VAUX inputs.

The MAX5954L EV kit is fully assembled and tested.Follow these steps to verify board operation. Do notturn on the power supply until all connections arecompleted.

Note: The banana leads connecting the 12V and 3.3Vpower supply to the EV kit must be short (< 12in long).

MAX5954L Hardware-Only Configuration1) Verify that a shunt is installed on jumper JU1

(PRES-DET).

2) Verify that a shunt is not installed on jumper JU2 (MRL).

3) Verify that shunts are installed on pins 1 and 2 ofjumpers JU3 and JU4 (local switch control).

4) Utilizing short 10A-rated banana leads (< 12inlong), connect the 12V DC power supply to theVIN1 banana jack. Utilizing short 10A-ratedbanana leads (< 12in long), connect the supplyground to the GND banana jack.

5) Utilizing short 10A-rated banana leads (< 12inlong), connect the 3.3V DC power supply to theVIN2 banana jack. Utilizing short 10A-ratedbanana leads (< 12in long), connect the supplyground to the GND banana jack.

6) Connect the 3.3V DC power supply to the VIN3banana jack with a short banana lead.

7) Connect a voltmeter to the 12V pad or test pointTP13 and GND. Connect a voltmeter to the 3.3Vpad or test point TP16 and GND. Connect a volt-meter to the 3.3VAUX pad or test point TP19 and GND.

8) Set switches SW3 (ON) and SW2 (AUXON) to theOFF position.

9) Turn on both power supplies in any sequence.

10) Set switches SW3 (ON) and SW2 (AUXON) to theON position.

11) Verify that the voltage at the following pads is asshown below:

12V = 12V

3.3V = 3.3V

3.3VAUX = 3.3V

12) Sliding switches SW3 and SW2 to the OFF positiondisables the respective output on the MAX5954LEV kit single hot-plug controller main or auxiliaryoutputs.

13) Test points TP14, TP17, and GND pads nearby areprovided to observe MOSFETs N1 or N2 gate volt-age, respectively, with an oscilloscope.

Software and Hardware Quick StartThe MAX5954L EV kit is fully assembled and tested.Follow these steps to verify board operation. Do notturn on the power supplies until all connections arecompleted.

Required Equipment:

• One each of the following DC power supplies

12V, 7A

3.3V, 5A (used to power the main 3.3V and3.3VAUX inputs)

• MAX5954L EV kit and CMAXQUSB interface board

• Windows 98/2000/XP computer with a spare USBport

• USB I/O extension cable, straight-through, male-to-female cable

• Three voltmeters for confirming output voltages

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MAX5954L Evaluation Kit/Evaluation System

_______________________________________________________________________________________ 3

SUPPLIER PHONE WEBSITE

DiodesIncorporated

805-446-4800 www.diodes.com

IRC 361-992-7900 www.irctt.com

Murata 770-436-1300 www.murata.com

Panasonic 714-373-7366 www.panasonic.com

SanyoElectronicDevice

619-661-6835 www.sanyodevice.com

TDK 847-803-6100 www.component.tdk.com

Vishay — www.vishay.com

Component Suppliers

Note: Indicate that you are using the MAX5954L when contact-ing these component suppliers.

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MAX5954L Evaluation Kit/Evaluation System

4 _______________________________________________________________________________________

MAX5954L Software and Hardware Configuration1) Verify that a shunt is not installed on jumper JU1

(PRES-DET) and a shunt is installed on jumper JU2(MRL).

2) Verify that shunts are installed on pins 2 and 3 ofjumpers JU3 and JU4 (computer control) on theEV kit.

3) Utilizing short 10A-rated banana leads (< 12inlong), connect the 12V DC power supply to theVIN1 banana jack. Utilizing short 10A-ratedbanana leads (< 12in long), connect the supplyground to the GND banana jack.

4) Utilizing short 10A-rated banana leads (< 12inlong), connect the 3.3V DC power supply to theVIN2 banana jack. Utilizing short 10A-ratedbanana leads (< 12in long), connect the supplyground to the GND banana jack.

5) Connect the 3.3V DC power supply to the VIN3banana jack with a short banana lead.

6) Connect a voltmeter to the 12V pad or test pointTP13 and GND. Connect a voltmeter to the 3.3Vpad or test point TP16 and GND. Connect a volt-meter to the 3.3VAUX pad or test point TP19 and GND.

7) Connect the CMAXQUSB interface board to theMAX5954L EV kit’s J4 connector.

8) Set both CMAXQUSB interface board SW1 switchesto enable. These provide pullup resistors for theSDA and SCL 2-wire bus signals.

9) Install the MAX5954L evaluation software on yourcomputer by running the INSTALL.EXE program onthe CD-ROM disk. The program files are copiedand icons are created for them in the Windows StartMenu. Restart the computer when prompted. ForWindows 2000 and XP, you may need administratorprivileges.

10) Turn on the 12V and 3.3V power supplies for the EVkit. The CMAXQUSB interface board is poweredthrough the computer’s USB port.

11) Connect the included USB cable from the PC to theCMAXQUSB interface board. A Building DriverDatabase window should pop up in addition to aNew Hardware Found message. If you do not seeany window that is similar to the one describedabove after 30s, try removing the USB cable fromthe CMAXQUSB interface board and reconnect itagain. Administrator privileges are required to installthe USB device driver on Windows 2000 and XP.

12) Follow the directions of the Add New HardwareWizard to install the USB device driver. Choose theSearch for the best driver for your device option.Specify the location of the device driver asC:\Program Files\MAX5954L using the Browse but-ton. Refer to the document Troubleshooting USB.PDFincluded with the software for more information.

13) Start the MAX5954L program by opening its icon inthe Start Menu.

14) Install the shunt on jumper JU1 (PRES-DET) orinsert a PCI Express card into connector J1.

15) The software detects the CMAXQUSB interfaceboard, the SMBus address of U2, and updates thestatus screen. The software is then ready forchanges in the command section.

See the MAX7313 Input/Output Expander and SMBusInterface section for configuring the input/outputexpander, using the CMAXQUSB interface board. Seethe Detailed Description of Software in this documentfor more information on the software GUI features.

Detailed Descriptionof Hardware

The MAX5954L EV kit demonstrates a PCI Express x16single hot-plug circuit design. A PCI Express x16 singlechannel is provided to evaluate a PCI Express x16 linecard. The EV kit uses a latching MAX5954L hot-plugcontroller in a 36-pin TQFN package to control the out-put power and monitor for faults.

The MAX5954L IC controls output power independentlyand external n-channel MOSFETs are used to controlpower to the 12V and 3.3V outputs. Current-sensingresistors (R1, R15) are used for monitoring current atthe 12V and 3.3V outputs. An internal MOSFET on theMAX5954L controls the 3.3V-auxiliary output.

If an overcurrent fault persists, the MAX5954L shutsdown the channel. The fault is reported at the open-drain power-good pin (PWRGD) and fault pin (FAULT).The MAX5954L power-on reset (POR) is configured fora default value of 160ms; however, the POR can bereconfigured by installing resistor R11.

Slide switches are provided to enable/disable the mainoutput (SW3) and auxiliary (SW2) 3.3V output indepen-dently when the SMBus control is not used. JumperJU1 can be used to provide a presence-detect functionif a PCI Express card is not used. Momentary pushbut-ton switch SW1 is provided to demonstrate theMAX5954L debounced logicgate input andoutput signals.

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MAX5954L Evaluation Kit/Evaluation System

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The MAX5954L EV kit features green LEDs connectedto the 12V, 3.3V, and 3.3V-auxiliary outputs that indi-cate if the respective output is currently powered. Redtest points for the 12V and 3.3V outputs, various PCIExpress signals, and other circuit signals (such as thegate drive of each MOSFET) have been provided forprobing on the EV kit board. All of the EV kit’s black testpoints are GND points.

The EV kit also features PC board pads for installingexternal resistors and capacitors near each MOSFETgate terminal to slow the MOSFETs gate-turn-on time.Surface-mount 0805 case size components can beinstalled at these locations. See Figure 3 for each of theMOSFETs’ gate reference designators.

When adding capacitance to the gates of N1 and N2,ensure that adequate startup time (tSU) is allowed. Tosuccessfully power up, the 5µA gate-charge currentmust be able to bring the gate voltages of N1 and N2above their maximum PWRGD thresholds before tSUhas elapsed. The maximum PWRGD threshold for 12VMOSFET N1 is 4.8V above V12VIN, and the threshold for3.3V MOSFET N2 is 4.5V above V3.3VIN. The timerequired to reach these thresholds is

The EV kit can be reconfigured for evaluating a x1, x4,or x8 PCI Express single hot-plug design by replacingcurrent-sense resistor R1. Consult the appropriate PCIExpress specification or Table 1 in the MAX5954L ICdata sheet for selecting other designs. PC board padsare provided to demonstrate the MAX5954L hot-plugfeatures without using the PCI Express x16 connector.

For evaluating external DC loads, the cables connect-ing the 12V and 3.3V outputs to the external DC loadmust be rated for at least 10A and be shorter than 12in.Additionally, current-sense resistors R1 and R15 areconfigured for the maximum allowable output currenton the 12V and 3.3V outputs. These resistors should bereconfigured only for lower output currents.

The MAX5954L EV kit features a MAX7313 16-port I/Oexpander (U2) and PC board pads for interfacing to auser’s SMBus system. Resistors R20–R25 configure theMAX7313 SMBus serial address. The MAX7313 can beused to enable/disable the EV kit’s main outputs andauxiliary 3.3V output independently. See the MAX7313Input/Output Expander and SMBus Interface sectionfor more details.

Jumper and Switch SelectionSeveral jumper and switch selections in the followingtables display the functions provided by the MAX5954LEV kit.

Presence DetectThe MAX5954L EV kit features a jumper that can simu-late a PCI Express x16 card being plugged into con-nector J1. Jumper JU1 is used to provide a presence-detect function for the channel. An external load (resis-tive and capacitive) must be connected to the chan-nel’s output PC board pads to simulate a real PCIExpress card. Table 1 lists the various jumper options.

Channel Enable/Disable SwitchesThe MAX5954L EV kit features two switches toenable/disable the 12V/3.3V main and 3.3V-auxiliaryoutputs. The switches can also be used to reset thechannel when it has latched off after a fault hasoccurred. Table 2 lists the various switch options.

total gate capaci ce PWRGD threshold voltageA

tan ×5µ

Table 1. Channel Presence-DetectFunctions

JUMPER SHUNTMAX5954L PINCONNECTION

EV KIT OPERATIONSIMULATED

JU1 InstalledPRES-DET pinpulled low

PCI Express cardinserted in channel

JU1 None*PRES-DET pinpulled high

No PCI Express cardin channel

*When using a real PCI Express card, this jumper’s shunt mustbe removed so that the card has control of the presencedetection.

Table 2. Channel Switch Functions

SWITCHSWITCHSTATE

MAX5954L PINCONNECTION

MAX5954LOPERATION

SW3 OnON pin pulledhigh

Enable mainoutputs

SW3 Off ON pin pulled lowDisable mainoutputs

SW2 OnAUXON pin pulledhigh

Enable 3.3V-auxiliary output

SW2 OffAUXON pin pulledlow

Disable 3.3V-auxiliary output

*When using a real PCI Express card, this jumper’s shunt mustbe removed so that the card has control of the presencedetection.

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A Control Methods, Other Configurations,and I/O Expander

Fault ResettingThe MAX5954L EV kit features two slide switches toreset a latched fault at the channel. The respectiveswitch resets the MAX5954L and unlatches faults whentoggled from on to off. See Table 2 for resetting thechannel. Refer to the MAX5954L data sheet for addi-tional functions of the MAX5954L ON pin.

Fault Timeout and POR PeriodsThe MAX5954L fault timeout period is configured for adefault value of 10ms and can be reconfigured to anew timeout period by installing surface-mount resistorR10. The MAX5954L POR timeout period is configuredfor a default value of 160ms, however a new POR time-out period can be reconfigured by installing surface-mount resistor R11. Refer to the MAX5954L data sheetApplications Information section for selecting the val-ues of resistors R10 or R11.

When adjusting the tFAULT timeout, be sure to allowadequate startup time, tSU. The minimum requiredstartup time for a given output is the greater of either

as described in the Detailed Description of Hardwaresection. Refer to the MAX5954 data sheet for moreinformation on selecting RTIM and RPORADJ.

Forced On InputsThe PCI Express slot can be forced to turn on regard-less of the MAX5954L logic status inputs. To force thechannel on, install surface-mount resistor R12. A typicalvalue is less than 1kΩ.

Current LimitingThe MAX5954L EV kit can evaluate other current-limitconfigurations for the 12V and 3.3V main outputs.Resistor R1 sets the 12V current limit and R15 sets the3.3V current limit. The 3.3V-auxiliary current limit isfixed at 470mA (typ) and is not reconfigurable. Refer tothe MAX5954L IC data sheet for information on select-ing other current-limit resistors.

Evaluating Other MAX5954L Hot-Plug ControllersThe MAX5954L EV kit can be used to evaluate theMAX5954A. Replace U1 with the MAX5954A that canbe ordered by contacting the factory.

MAX7313 Input/Output Expander and SMBusInterface

The MAX5954L EV kit features a MAX7313 I/Oexpander (U2) and PC board pads for connecting to anSMBus system (SDA and SCL signals). The I/Oexpander interfaces with the PRES-DET, FAULT, ON,and OUT signals of the MAX5954L. A 9-pin header, J2,is provided to enable easy access to each signalthrough a ribbon cable or scope probe. Green and yel-low LEDs (D3, D4) are also provided for user applica-tions such as status indication. Jumper JU2 (MRL) isprovided to mimic a PCI Express mechanical retentionlocking (MRL) signal. Surface-mount resistors R20–R25configure the MAX7313 SMBus address, which is set to0x40 by default.

If the MAX7313 I/O expander is used to control theMAX5954L ON/AUXON signals and read back the vari-ous other signals, jumpers JU3 and JU4 must bereconfigured or U2 may be destroyed when switchinglogic states. See Table 3 below for configuring jumpersJU3 and JU4. Pads are provided on the EV kit’s PCboard for interfacing with a user’s system SMBus VDD,SDA, SCL, and GND signals if the CMAXQUSB inter-face board is not used.

If a user’s SMBus system is not available, a Windows-based computer can be interfaced with the EV kit byconnecting the CMAXQUSB interface board to connec-tor J4. The CMAXQUSB interface board enables thecomputer to interface with the EV kit’s SMBus signals.The interface board and GUI software provides theuser with the capability of controlling and monitoringthe MAX5954L IC using the MAX7313 I/O expander.

PWRGD threshold voltage input voltageoutput load capaci ce

Aor

total gate capaci ce PWRGDthresholdvoltage

A

+ ×

×

tan

tan

5

5

µ

µ

MAX5954L Evaluation Kit/Evaluation System

6 _______________________________________________________________________________________

Table 3. MAX5954L Channel ON SignalsConfiguration

JUMPERSHUNT

LOCATIONMAX5954L PINCONNECTION

EV KITOPERATION

JU4 1 and 2ON controlled bySW3

Local switchcontrol

JU3 1 and 2AUXONcontrolled by SW4

Local switchcontrol

JU4 2 and 3ON controlled byU2, MAX7313with SMBus

SMBus orcomputercontrol

JU3 2 and 3

AUXONcontrolled by U2,MAX7313 withSMBus

SMBus orcomputercontrol

Detailed Descriptionof Software

Words in boldface are user-selectable features in theMAX5954L EV kit software. A mouse or the keyboard’stab key is used to navigate various items on the MainWindow. Most of the main window’s available functionsand a few more can be evaluated by using the pulldown menu. The software features a demo mode that is available using the View|Demo Modepulldown menu.

Software StartupUpon starting the program, the MAX5954L EV kit soft-ware automatically detects U2 address and configures

its I/O. See Table 4 for U2’s configuration by the soft-ware. The MAX5954L EV kit’s various status signals arethen updated by the program approximately every500ms. Use the checkboxes to enable/disable variousEV kit functions and then select the ExecuteCommand button to send the commands to U2 and/orU1. Deselecting a checkbox disables the command.

The software’s Status area provides information on thevarious MAX5954L and PCI Express system signalscondition. The MAX7313 U2 SMBus address is provid-ed in hexadecimal and decimal format, respectively.The left bottom status bar of the main window providesthe CMAXQUSB interface board communication status.The right bottom status bar provides the current pro-

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MAX5954L Evaluation Kit/Evaluation System

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Figure 1. MAX5954L Evaluation Software Main Window for Reading Current EV Kit Status and Sending Commands

Table 4. MAX7313 I/O Port Configuration/Function

MAX7313PORT I/O

PORT P7(BIT D7)

PORT P6(BIT D6)

PORT P5(BIT D5)

PORT P4(BIT D4)

PORT P3(BIT D3)

PORT P2(BIT D2)

PORT P1(BIT D1)

PORT P0(BIT D0)

Port Config OUTPUT OUTPUT INPUT INPUT OUTPUT OUTPUT INPUT INPUT

EV KitFunction

YELLOWLED (D4)

GREEN LED(D3)

PRES-DET FAULT AUXON ON OUT MRL

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gram status and SMBus communication status withrespect to U2.

The MAX5954L EV kit software configures the CMAXQUSB interface board’s SMBus communicationspeed to 400kHz by default. The speed can bereduced to 100kHz if required, by selecting the pull-down menu’s View|2-Wire Speed|100kHz selection.This may be required if slower SMBus or 2-wire devicesare connected to the bus on the EV kit.

General-Purpose 2-Wire Interface UtilityThe general-purpose 2-wire interface utility can also beused to communicate with the MAX7313 and control orread back signals from the MAX7313 and/or MAX5954L.Use the View|Interface pulldown menu to access theutility. The utility configures the SMBus interface para-meters such as start and stop bits, acknowledgements,and clock timing. The 2-wire interface screen allows theuser to send general-purpose SMBus commands usingthe SMBusWriteByte and SMBusReadByte. The inter-

face utility only accepts and outputs hexadecimal num-ber format.

The Hunt for active listeners button scans the entire2-wire address space, reporting each address that isacknowledged. The SMBusWriteByte transmits thedevice address, command, and one byte of data. TheSMBusReadByte transmits the device address, a com-mand, and then retransmits the device address andreads 1 byte of data. For information on the differencesbetween a 2-wire and an SMBus interface, read appli-cation note “Comparing the I2C Bus to the SMBus” atwww.maxim-ic.com

General TroubleshootingProblem: software reports it cannot find the inter-face board.

• Is the interface board power LED lit?

• Is the USB communications cable connected?

MAX5954L Evaluation Kit/Evaluation System

8 _______________________________________________________________________________________

Figure 2. 2-Wire Interface Window (Provides Direct, Low-Level Access to the MAX5954L with the MAX7313 and SMBus 2-Wire Interface)

• Has Windows plug-and-play detected the board?Bring up Control Panel->System->Device Manager,and look at what device nodes are indicated forUSB. If there is an “unknown device” node attachedto the USB, delete it—this forces plug-and-play totry again.

Problem: Unable to find U2 (MAX7313)

• Is power applied to the MAX5954L EV kit VIN2 andVIN3 banana jacks? This is required for powering U2.

• Are the SCL and SDA signals pulled up to VDD?The CMAXQUSB interface board dip switch SW1enables the on-board resistors on the interfaceboard. There must be pullup resistors somewherefor the SMBus SCL and SDA signals.

• If using jumper wires to connect, are the SCL andSDA signals swapped? Is the ground return missing?

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MAX5954L Evaluation Kit/Evaluation System

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Figure 3. MAX5954L EV Kit Schematic

12V

GND(12V)VIN1

(3.3V)VIN2

(3.3V AUX)VIN3GND

GND

GND

GND

GND

GND

GNDTP4

GNDTP5

GNDTP6

GNDTP7

GNDTP8

GNDTP9

GNDTP10

GNDTP11

GNDTP12

VIN2

3

2 1

8 7

5 64

4

3

2 1

8 7

5 6

GND

GND

GND

GND

GND

JU1

ATTN

SW1

N.C.

N.C.

T2

T1

N.C.

N.C.

N.C.

N.C.

N.C.

PRES-DET

PRES_DET

FON

ON

U1

ON

AUXONAUXON

12S+12S+

12S-12S-

12G12G

GND

GNDGND

GND

GND

GND

N35

GND

GND

AUX0

3.3VAUXD6

3.3VAUX

3.3VD5

3.3V

TP17 VIN3

VIN2

R1910kΩ

R1810kΩ

R28150Ω

R17OPEN

R16150Ω

R150.005Ω

1%

C81µF

C91µF

C120.1µFC14

OPEN

3.3S+

3.3G

PORA

DJ

PGND GN

D

12VI

N

INPU

T

OUTP

UT N.C.

N.C. TIM

FAULT

PWRGD

3.3V

AUXO

3.3V

AUXI

N

N.C.

N.C.

N.C.

N.C.

3.3S-

12G

12S-

12S+

N1S

TP14

TP1 TP2 TP3

VIN3

12VTP13

R10OPEN

C11500µF

16V

R2750Ω

C71µF

C23300µF

6.3V

C410µF

C510µF

C310µF

GND

C61µF

12VD2

R31kΩ

R4OPEN

R12OPEN

C13OPEN

R11OPEN

VIN2

D3

D1

N1

N2

7P6

P5

OUT

TP15

OUTGN

D GND

P4 P3 P2 P1 P0

AD2 A2

GND

GND

VIN3

VIN2

VIN3

JU3

SW2

VIN 3 VIN 3

SW3

JU4

VIN3OUT

P11

P12

P13

P14

P15

P16

AUXO

N

AUXON

ON

PRES-DET

ON

FAULT

AD1U2

A1

INT/O16 INT

V+

SDA SDA

SCL SCL

GND

A0 A1 A2

P7

GND

GND P8

P9

P10

8

9

10

11

12

24

23

22

21

20

19

13 14 15 16 17 18

6 5

JU2MRL

R810kΩ

R93.3kΩ

R651kΩ

R751kΩ

C110.1µF

R20OPEN

R21OPEN

R22OPEN

R2310kΩ

R2410kΩ

R2510kΩ

4 3 2 1

2829303133343536 32

18

27

262

1

1

25

24

23

22

21

20

19

FAULTPWRGD

TP18

3.3VAUXONTP19

PWRGD

FAULT

3

3

4

5

6

7

8

9

17161513121110 14

11

33

22

11

3

3

22

GREEN

YELLOWD4

R13150Ω

R510kΩ

R14150Ω MAX7313

NOTE: FOR U1, IC PADDLE CONNECTS TO PIN 34 ONLY AND PIN 35 HAS A DEDICATED TRACE TO GND BANANA JACK.

MAX5954L

3.3VTP16

TP20

R10.008Ω

VIN3

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MAX5954L Evaluation Kit/Evaluation System

______________________________________________________________________________________ 11

Figure 4. MAX5954L EV Kit Schematic, PCI Express X16 Connectors

B1 B2 B3 B4 B5 B6 B7 B8 B9 B10

B11

B12

B13

B14

B15

B16

B17

B18

B19

B20

B21

B22

B23

B24

B25

B26

B27

B28

B29

B30

B31

B32

B33

B34

B35

B36

B37

B38

B39

B40

B41

A41

A40

A39

A38

A37

A36

A35

A34

A33

A32

A31

A30

A29

A28

A27

A26

A25

A24

A23

A22

A21

A20

A19

A18

A17

A16

A15

A14

A13

A12

A11

A10

A9A8A7A6A5A4A3N1

S

N3S

PERS

T#_J

1

N1S N3

S

PRES-DET

A2A1

AUX0

GND

GND

PETP

6GN

DGN

DPE

TN5

PETP

5GN

DGN

DPE

TN4

PETP

4GN

DPR

SNT2

#RS

VDGN

DPE

TN3

PETP

3GN

DGN

DPE

TN2

PETP

2GN

DGN

DPE

TN1

PETP

1GN

DPR

SNT2

#GN

DPE

TN0

PETP

0GN

DRS

VDW

AKE#

3.3V

AUX

JTAG

1+3

.3V

GND

SMDA

TSM

CLK

GND

+12V

+12V

+12V

GND

PERN

5PE

RP5

GND

GND

PERN

4PE

RP4

GND

RSVD

RSVDGN

DPE

RN3

PERP

3GN

DGN

DPE

RN2

PERP

2GN

DGN

DPE

RN1

PERP

1GN

DRS

VDGND

PERN

0PE

RP0

PETN

0RE

FCLK

-RE

FCLK

+GN

DPE

RST#

+3.3

V+3

.3V

JTAG

5JT

AG4

JTAG

3JT

AG2

GND

+12V

+12V

PRSN

T1#

B42

J1-B

J1-A

B43

B44

B45

B46

B47

B48

B49

B50

B51

B52

B53

B54

B55

B56

B57

B58

B59

B60

B61

B62

B63

B64

B65

B66

B67

B68

B69

B70

B71

B72

B73

B74

B75

B76

B77

B78

B79

B80

B81

B82

A82

A81

A80

A79

A78

A77

A76

A75

A74

A73

A72

A71

A70

A69

A68

A67

A66

A65

A64

A63

A62

A61

A60

A59

A58

A57

A56

A55

A54

A53

A52

J2-1

J2J4

PERS

T#_J

1

PRES-DET

FAULT

PWRGD

INT

J2-2

J2-3

ON AUXO

N

OUT

GND

J2-4

J2-5

J2-6

J2-7

J2-8

J2-9

A51

A50

A49

A48

A47

A46

A45

A44

PRES-DET

PRES-DET

A43

A42

GND

GND

RSVD

PCI-1

6EX

PCI-1

6EX

PRSN

T2#

GND

PETN

15PE

TP15

GND

GND

PETN

14PE

TP14

GND

GND

PETN

13PE

TP13

GND

GND

PETN

12PE

TP12

GND

GND

PETN

11PE

TP11

GND

GND

PETN

10PE

TP10

GND

GND

PETN

9PE

TP9

GND

GND

PETN

8PE

TP8

GND

PRSN

T2#

GND

PETN

7PE

TP7

GND

GND

PETN

6

GND

PERN

15PE

RP15

GND

GND

PERN

14PE

RP14

GND

GND

PERN

13PE

RP13

GND

GND

PERN

12PE

RP12

GND

GND

PERN

11PE

RP11

GND

GND

PERN

10PE

RP10

GND

GND

PERN

9PE

RP9

GND

GND

PERN

8PE

RP8

GND

RSVDGN

DPE

RN7

PERP

7GN

DGN

DPE

RN6

PERP

6GN

D

J4-1

J2-2

J2-4

J2-6

J2-8

J2-1

0J2

-12

J2-1

4J2

-16

J2-1

8J2

-20

N.C.

GND

GND

GND

GND

TP31

TP32

VDD

VDD

VDD

J4-3

SDA

SDA

SDA

J4-5

GND

J4-7

SCL

N.C.

N.C.

N.C.

SCL

SCL

J4-9

SUSP

ENDO

UT

SUSP

ENDO

UT

J4-1

1

J4-1

3

J4-1

5

J4-1

7

J4-1

9

ALER

TIN

ALER

TIN

FEM

ALE

CONN

ECTO

R 2

x 10

PRES-DET

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12 ______________________________________________________________________________________

Figure 5. MAX5954L EV Kit Component Placement Guide—Component Side

Figure 6. MAX5954L EV Kit PC Board Layout—Component Side

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______________________________________________________________________________________ 13

Figure 7. MAX5954L EV Kit PC Board Layout—Inner Layer, Ground Plane

Figure 8. MAX5954L EV Kit PC Board Layout—Inner Layer, Power Plane

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600

© 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.

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MAX5954L Evaluation Kit/Evaluation System

Figure 9. MAX5954L EV Kit PC Board Layout—Solder Side

Figure 10. MAX5954L EV Kit Component Place Guide—Solder Side