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Copyright 2004 National Semiconductor Corporation
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3.0 Functional Description
The LM32/LM40/LM41 Evaluation Board, along
with the SensorEval Software, provides the
system designer with a convenient way to learn
about the operation of the LM32, LM40, or
LM41 Temperature Sensor chip. The user
simply has to install the SensorEval software on
his PC, run it, connect the USB cable from the
PC to the Evaluation Board, and the user can
read temperatures. It’s that simple! The user
doesn’t have to provide any power or external
signals to the evaluation board.
Power to the LM32/LM40/LM41 Evaluation
Board is taken from the USB 5-Volt line. This
+5VDC is the input to the on-board LM2950 low
dropout voltage regulator, which regulates the
output voltage to +3.3 VDC. This output voltage
powers the LM32, LM40, LM41, the on-board
microcontroller, and the EEPROM chip where
the board ID information is stored.
The microcontroller on the board provides the
single wire signal (SWD), provides the Address
(ADD) select signal, and relays the information
from the LM32, LM40, or LM41 to the PC via
the USB lines.
3.1 Evaluation Board Connection Tables
3.1.1 LM32 Evaluation Board Connections Only
Connector Label
Pin
Number
Description
J1 N/A
USB Cable Input. Connect the USB cable to this jack
after the SensorEval software has been loaded on the
PC.
1,2 NC
3,4 GND
5,6
3.3_SBY This is the +3.3V voltage supplied by the on-
board voltage regulator.
7,8
SWD This is the Single wire interface signal created
by the on-board microcontroller.
9,10
ADD This is the address select signal created by the
on-board microcontroller.
11,12 NC
J2
Output header
provides user with
signals for test
purposes only.
Do not apply any
external power or
signals to any of the
pins on these
headers!
13,14 NC
1,2 NC
3,4 NC
5,6 NC
7,8
D2+ This is the anode of the second remote diode
input.
9,10
D2- This is the cathode of the second remote diode
input.
11,12
D1+ This is the anode of the first remote diode input.
J3
Output header
provides user with
signals for test
purposes only.
Do not apply any
external power or
signals to any of the
pins on these
headers!
13,14
D1- This is the cathode of the first remote diode input.
J4, J5
These Headers are not used for evaluation board
purposes. They are not stuffed or used.
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