Datasheet

Detailed Description of Hardware
The MAX31850/MAX31851 EV kit hardware provides
everything needed to evaluate a K-type thermocouple. In
addition to a thermocouple and MAX31850, the hardware
includes a USB interface that is used to communicate
with the PC-based software. An added feature is that the
hard ware is USB powered, meaning that no power sup-
plies are needed.
Thermocouple Channels
The EV kit hardware features two thermocouple
channels. The top channel comes preconfigured with
a MAX31850KATB+, K-type thermocouple, and ther-
mocouple socket. A sec ond channel is provided to
make it easy to evaluate other thermocouple types. The
bottom channel is almost fully populated, missing only the
desired MAX31850 or MAX31851 version, correspond ing
thermocouple, and thermocouple socket. The following
section describes how to modify the hardware in order to
evaluate other thermocouple types.
Evaluating Other Thermocouple Types
To use the bottom channel, see Table 2 for the part num-
bers of the three items required for the desired thermo-
couple type.
Once the three items have been procured, power down
the EV kit by disconnecting the Micro-USB cable. Carefully
solder the Maxim device to the footprint labeled U3 and
the thermocouple socket to the footprint labeled TH2.
Finally, connect the thermocouple to the socket.
Reconnect the USB cable to the EV kit and then run the
software. In the Device menu on the GUI, select the
Search for ROMs option. Two devices should be found
and shown in the ROM Codes drop-down list. Select the
correct Thermocouple Type in the table and the device
is ready to be evaluated.
User-Supplied 1-Wire interface
To communicate with the devices with a user-supplied
1-Wire interface, first disconnect the USB and remove
resistor R218 to disconnect the on-board interface.
Connect the off-board 1-Wire interface to the GND, DQ,
and 3.3V test points for the externally powered mode. If
parasite-power mode is configured on JP1 and JP2, only
the GND and DQ test points need to be connected to the
user-supplied interface.
Power Conguration
To power the device externally with 3.3V, move both jumpers
on JP1 and JP2 to the 3.3V position on the right. For para-
site power, move JP1 and JP2 to the GND and DQ position
on the left. See Table 3 for the jumper descriptions.
*Thermocouple and socket part numbers are Omega part numbers. Contact Omega for RoHS part numbers.
Table 2. Items for Other Thermocouple Types
TYPE PART THERMOCOUPLE* SOCKET*
K MAX31850KATB+ 5SRTC-GG-K-24-36 PCC-SMP-K-5
J MAX31850JATB+ 5SRTC-GG-J-24-36 PCC-SMP-J-5
N MAX31850NATB+ NMQIN-010E-6 (unveried) PCC-SMP-N-5
T MAX31850TATB+ 5SRTC-GG-T-24-36 PCC-SMP-T-5
E MAX31850EATB+ 5SRTC-GG-E-24-36 PCC-SMP-E-5
S MAX31851SATB+ — —
R MAX31851RATB+ — —
Evaluates:
MAX31850/MAX31851
MAX31850/MAX31851 Evaluation Kit
www.maximintegrated.com
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