MAX31855 Evaluation Kit Evaluates: MAX31855

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1 General Description The MAX8 evaluation kit (EV kit) provides the hardware and software (GUI) necessary to evaluate the MAX8 cold-junction compensated thermocouple-todigital converter. The MAX8 EV kit comes with a MAX8KASA+ soldered to the PCB. This is the K-type thermocouple version of the MAX8. Other thermocouple types can be evaluated by procuring the desired thermocouple, thermocouple socket, and corresponding MAX8. Contact the factory for free samples of the MAX8 to match your desired thermocouple type. See the Evaluating Other Thermocouple Types section for part numbers and additional information regarding other thermocouple types. EV Kit Contents S Assembled Circuit Board Including MAX8KASA+ S Mini-USB Cable S K-Type Thermocouple Ordering Information appears at end of data sheet. Features S Includes Everything Needed to Evaluate a K-Type Thermocouple S EV Kit Hardware is USB Powered (USB Cable Included) S Windows XP, Windows Vista, and Windows 7 Operating Systems-Compatible Software S USB HID Interface S Graphical User Interface (GUI) Consists of a Single.EXE File S Second Channel Allows Easy Evaluation of Other Thermocouple Types S RoHS Compliant MAX8 EV Kit Files FILE DESCRIPTION MAX8EVkit.EXE Application program Note: The.EXE file is downloaded as a.zip file. MAX8 EV Kit Board Windows XP, Windows Vista, and Windows are registered trademarks of Microsoft Corp. For pricing, delivery, and ordering information, please contact Maxim Direct at , or visit s website at ; Rev 0; 0/

2 Quick Start Note: In the following sections, software-related items are identified by bolding. Text in bold refers to items directly from the EV kit software. Text in bold and underlined refers to items from the Windows operating system. Required Equipment PC with Windows XP, Windows Vista, or Windows 7 OS with a spare USB port K-type thermocouple (included) Mini-USB cable (included) EV kit hardware Procedure Follow the steps below to get started measuring temperature using the MAX8 interfaced to a K-type thermocouple. ) Connect the included K-type thermocouple to J (thermocouple socket) of the EV kit hardware. One terminal of the thermocouple is wider than the other, ensuring proper polarity. ) Ensure that jumper/shunt J is installed and is selecting Channel. ) Set the EV kit hardware on a nonconductive surface that ensures nothing on the PCB gets shorted together. ) Prior to starting the GUI, connect the EV kit hardware to a PC using the supplied mini-usb cable, or equivalent. The COM LED (D) should flash between red and orange. ) Windows should automatically begin installing the necessary device driver. The USB interface of the EV kit hardware is configured as an HID device and therefore does not require a unique/custom device driver. Once the driver installation is complete, a Windows message appears near the System Icon menu indicating that the hardware is ready to use. Do not attempt to run the GUI prior to this message. If you do, you must close the application and restart it once the driver installation is complete. On some versions of Windows, Administrator privileges may be required to install the USB device. 6) Go to to download the latest version of the EV kit software, titled MAX8EVkit.ZIP. Save the EV kit software to a temporary folder. 7) Open the.zip file and extract the.exe file to your desired location. The.EXE file is the actual EV kit GUI and not an install program. You can store the.exe wherever you like and then uninstall it later by simply deleting the.exe file. 8) Once the device driver installation is complete (from an earlier step), double-click the.exe file to run 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 Run. 9) When the GUI appears, the EV Kit Status group box should indicate that the EV kit hardware is ready. Also, the COM LED (D) should turn green. 0)Click the Single Read button to read the temperature. A valid temperature should be displayed along with all four Alarm Status indicators remaining green. At this point, the EV kit and setup is fully functional and ready to begin evaluating the MAX8. If any issues arise, see the Troubleshooting section. Detailed Description of Software Figure shows a screenshot of the MAX8 GUI. EV Kit Status Section On the right-hand side of the GUI is a section titled EV Kit Status. It is used to indicate the status of the communication between the GUI and the EV kit hardware. If everything is working properly, a message indicates that the hardware is present and/or ready. Otherwise, EV Kit not found. is displayed. Thermocouple Type Section The drop-down box in this section is used to select the thermocouple type installed on the EV kit hardware. See Table for the list of possible settings. Out-of-the-box, the hardware contains a K-type version of the MAX8 along with a K-type thermocouple and socket. Therefore, the drop-down box defaults to the K-type setting. The thermocouple type selection is used by the GUI to calculate the linearized temperature values. Table. Thermocouple Types and Sensitivities TYPE SENSITIVITY (µv/nc) K*.76 J 7.9 N 6.6 S 9.87 T.8 E 76.7 R 0.06 *Default setting.

3 Figure. MAX8 EV Kit GUI Read from the MAX8 Section Interfacing to the MAX8 is simple. The interface is read-only and consists of one -bit shift register. When the Single Read button is pressed, all bits are read, parsed, and then displayed. The raw data read from the device is shown in both binary and hexadecimal format in the edit boxes labeled Raw B[:0]. Furthermore, the four fault bits are analyzed and then their states are indicated in the Alarm Status section. The Raw Thermocouple Temperature and Cold Junction Temperature edit boxes are calculated. And finally, the Linearized Thermocouple Temperature edit box is calculated using the sensitivity value and NIST coefficients to compensate for thermocouple nonlinearities. Refer to the MAX8 IC data sheet for additional information. Multiple Reads Section This section allows the user to enter a desired number of samples (temperature readings) as well as the delay between the samples (in milliseconds) in order to automate temperature readings. It is also possible to write the results to a file by clicking the Log to file checkbox and providing a folder and filename for the comma separated value (.CSV) file to be stored.

4 Detailed Description of Hardware The MAX8 EV kit hardware provides everything needed to evaluate a K-type thermocouple. In addition to a thermocouple and MAX8, the hardware includes a USB interface that is used to communicate with the PC-based software. An added feature is that the hardware is USB powered, meaning that no power supplies are needed. Thermocouple Channels The EV kit hardware features two thermocouple channels. Channel comes preconfigured with a MAX8KASA+, K-type thermocouple, and thermocouple socket. A second channel is provided to make it easy to evaluate other thermocouple types. Channel is almost fully populated, missing only the desired MAX8 version, corresponding thermocouple, and thermocouple socket. A jumper (J) is used to select the desired channel. The following section describes how to modify the hardware in order to evaluate other thermocouple types. Evaluating Other Thermocouple Types To use Channel, see Table for the part numbers of the three items required for the desired thermocouple type. Once the three items have been procured, carefully solder the Maxim device to the footprint labeled U and the thermocouple socket to the footprint labeled J. Obviously, make sure this is done with the board unpowered. Move the jumper, J, to the Channel position. Finally, connect the thermocouple to the socket. Reconnect the USB cable to the PC and then run the GUI. Select the correct Thermocouple Type from the drop-down box. The hardware and software are now ready to begin evaluation. Description of Channel Selection Jumper The jumper, J, is used to select the desired channel. See Table for additional details. Table. Items Required to Evaluate Other Thermocouple Types TYPE MAXIM PART THERMOCOUPLE* SOCKET* K MAX8KASA+ SRTC-GG-K--6 PCC-SMP-K- J MAX8JASA+ SRTC-GG-J--6 PCC-SMP-J- N MAX8NASA+ NMQIN-00E-6 (unverified) PCC-SMP-N- S MAX8SASA+ T MAX8TASA+ SRTC-GG-T--6 PCC-SMP-T- E MAX8EASA+ SRTC-GG-E--6 PCC-SMP-E- R MAX8RASA+ *Thermocouple and socket part numbers are Omega part numbers ( Contact Omega for RoHS part numbers. Table. MAX8 EV Kit Jumper Description (J) JUMPER JUMPER POSITION DESCRIPTION J *Default position. -* - Selects Channel. The SO (serial out) pin of the Channel MAX8 is connected to the USB PC Interface Selects Channel. The SO (serial out) pin of the Channel MAX8 is connected to the USB PC Interface

5 Troubleshooting All effort was made to ensure that each EV kit works on the first try directly out of the box. In the rare occasion that a problem is suspected, see the table below to help troubleshoot the issue. SYMPTOM CHECK SOLUTION Is the LED labeled D on? If yes, then the electronic fuse, U7, 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. GUI says hardware not found. GUI appears to work, but the raw data is all zeros. The Fault and Open Circuit indicators are red in the Alarm Status section of the GUI. Does the LED labeled D turn green when the GUI is running? Are any of the LEDs illuminated? Jumper (J) Is the thermocouple connected? If not, then exit the GUI and try running it again. If D still does not turn green, then exit the GUI and try connecting the USB cable to a different USB port on the PC and wait for a Windows message that states the hardware is ready to use. Run the GUI again. If not, then the PCB may not be getting power from USB. Try a different USB cable or a different USB port. Make sure jumper, J, is installed and connected to the correct channel. Verify that the thermocouple is connected (to the correct channel).

6 NOTE: U and J will be populated with K type thermocouple. J PCC-SMP-K--ROHS - + L BLM8PG7 060 L BLM8PG7 060 U in in NUP0 C C C 0.0uF NOTE: Second circuit available for customer to add another type of thermocouple U and J. J PCC-SMP-x-x L BLM8PG7 060 in in - + U NUP0 C7 C6 0.0uF L BLM8PG7 060 C8 NOTE: All R, C and L footprints are 080 unless otherwise stated. PCB Layout Notes. MAX8 should be as close as possible to the thermocouple connector.. Use as much copper as possible between MAX8 and connector (PCC-SMP-x-x).. Place decoupling CAP close to their voltage supply.. Use a large ground plane to improve the device s temperature measurement accuracy. C 0.uF V C 0.uF U T- T+ Vcc NC SO CS SCK MAX J SO Jumper m r T- T+ Vcc NC SO CS SCK U MAX TP SO TP TP SCK TP CS_BAR TP V V SO SCK CS TP9 TP0 TP TP TP6 TP7 TP8 Figure. MAX8 EV Kit Schematic (Sheet of ) 6

7 J Vbus D- D+ I.D. USB_PIN R 0 0 R 0 D- VBUS C9 R D+ 0.uF U7 IN ON OUT FLAG MAX787EXK+TCT-ND SC70-0 V V R6 R7 0 0 R.7K D R6 06 R8.7K R9 Reset Fault LED VDD C0 0.uF C uf U6 SHDN IN BP OUT MAX8868EUK-T SOT- C uf C 0.0uF R0 M X C CS R R U 8 MCLR P8/W_PU 7 P HB P7/W_DQ 6 COM_LED/BOOT P P USB_DET P VPO RCV VMO P6/CS P0/SCL/SCK P/SDA/SDI 0 OCS VDD 9 OSC 8 P P9/SDO UOE ENUM 7 6 PS_VAR D+/VP Vusb D-/VM PIC8LF0 SOIC 8-pin D+ D- R.9 R.9 V SCK SO 0MHz CRYSTAL_SM C pf C6 pf NOTE: All R, C and L footprints are 080 unless otherwise stated. V BOOTLOAD GREEN RED LED_BI-COLOR D R 0 Select Fixed Voltage R.7K V -Wire interface (Read Only) C8.0uF C9 0.uF C7 uf PCB notes: D, D, R and R9 must be on top layer. Figure. MAX8 EV Kit Schematic (Sheet of ) 7

8 Figure. MAX8 EV Kit PCB Layout Top Figure. MAX8 EV Kit PCB Layout Bottom 8

9 Component List DESIGNATION QTY DESCRIPTION C, C, C9, C0, C9 C, C6, C C, C, C7, C8, C C, C, C7, C8 0.FF X7R ceramic capacitors (080) Venkel C080X7R60-0KNE 0.0FF X7R ceramic capacitors (080) Venkel C080X7R0-0KNE 0 Do not populate (080) C, C6 D D J J J 0 J L-L R, R, R R, R8, R R6, R7, R6 FF X7R ceramic capacitors (080) Venkel C080X7R0-0KNE pf ceramic capacitors (080) Venkel C080COG0-0KNP Red LED (06) Kingbright APT6SURCK Red/green dual LED Kingbright BM0SURKCGKC -pin, female Mini-USB K-type thermocouple socket Omega PCC-SMP-K--ROHS Thermocouple socket Do not populate x header,.mm pitch I ferrite beads (060) BLM8PG7SND.9I Q% resistors (080) Venkel CR080-0W-R9FT.7kI Q% resistors (080) Venkel CR080-0W-70FT 0I Q% resistors (080) Venkel CR080-0W-00FT DESIGNATION QTY DESCRIPTION R0 MI Q% resistor (080) Venkel CR080-0W-00FT R, R, R, R 0I Q% resistor (080) Venkel CR080-0W-000FT R, R9 0 Do not populate (080) TP, TP, TP White test points Keystone 0 TP-TP8 Black test points Keystone 0 TP9, TP0 Red test points Keystone 00 TP, TP Do not populate U Thermocouple-to-digital converter (8 SO) Maxim MAX8KASA+ U, U TVS diode (SOT-) NUP0TLG U 0 MAX8 Do not populate U PIC8LF0-I/SO (8 SO) U6 Linear regulator ( SOT) Maxim MAX8868EUK+ U7 Current-limit switch ( SC70) Maxim MAX787EXK+ X 0MHz, 0pF SMT crystal 0IE0M00000 Jumper/shunt Mini-USB cable K-type thermocouple Omega SRTC-GG-K--6-ROHS PCB: MAX8 EV Kit Component Suppliers SUPPLIER PHONE WEBSITE Omega Engineering, Inc Venkel Ltd Note: Indicate that you are using the MAX8 when contacting these component suppliers. 9

10 PART MAX8EVKIT# Ordering Information TYPE EV Kit #Denotes a RoHS-compliant device that may include lead that is exempt under the RoHS requirements. 0

11 REVISION NUMBER REVISION DATE MAX8 Evaluation Kit DESCRIPTION Revision History PAGES CHANGED 0 0/ Initial release cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a product. No circuit patent licenses are implied. reserves the right to change the circuitry and specifications without notice at any time. 60 Rio Robles, San Jose, CA 9 USA Products, Inc. and the logo are trademarks of Products, Inc.

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