National LM95235 manual Functional Description, Connector Label, Number, Do not apply any

3.0 Functional Description

The LM95235 Evaluation Board, along with the SensorEval Software, provides the system designer with a convenient way to learn about the operation of the LM95235 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 the temperatures. It’s that simple! The user doesn’t have to provide any power or external signals to the evaluation board.

Power to the LM95235 Evaluation Board is taken from the USB 5-Volt line. This +5 VDC 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 LM95235, the on-board microcontroller, and the EEPROM chip where the board ID information is stored.

The microcontroller provides the SMBus Clock (SMBCLK) signal and the SMBus Data (SMBDAT) signal to the LM95235 chip. This communication between the LM95235 and the PC USB data lines is controlled by the microcontroller. For all of the details of this communication protocol see the latest LM95235 datasheet, available at www.national.com.

3.1 LM95235 Evaluation Board Connection Table

Connector Label	Pin	Description
	Number
J1	N/A	USB Cable Input. Connect the USB cable to this jack after
		the SensorEval software has been loaded on the PC.
		VDD. The +3.3 VDC voltage supplied by the on-board
	1	voltage regulator to the LM95235 VDD input pin. Do not
		connect an external power supply to this pin!
JP2	2	SMBDAT. Data signal for the SMBus.
Output header provides	3	SMBCLK. Clock signal for SMBus.
user with signals for test
purposes only.
		OS#/A0. When this pin is pulled low it enables the
Do not apply any	4	Overtemperature Shutdown (OS) feature. When this pin is
external power or		pulled high it is the Address pin function.
signals to any of the	5	No Connection.
pins on these headers!
	6	T_Crit#. This is the signal that goes low when the Set
		Temperature is exceeded.
	7	No Connection.
J4
Connection to	3, 4	Connect for D+ connection
temperature diodes
Do not apply any
external power or	1, 2	Connect for D- connection
signals to any of the
pins on these headers!

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