Measure negative temperature with Lm35

LM35 can measure temperatures from -55deg to 150deg and we need negative supply voltage for measuring this negative temperature.
This circuit eliminates the negative voltage power supply and this project can measure the negative temperature
Download the protesu file to simulate the project on your desktop
Measure negative temperature

Bascom Code

$regfile = "m16def.dat"
$crystal = 1000000
Config Lcd = 16 * 2
Config Lcdpin = Pin , Db4 = Portd.4 , Db5 = Portd.5 , Db6 = Portd.6 , Db7 = Portd.7 , E = Portd.0 , Rs = Portd.1
Config Adc = Single , Prescaler = Auto , Reference = Internal
Deflcdchar 0 , 12 , 18 , 18 , 12 , 32 , 32 , 32 , 32
Deflcdchar 1 , 32 , 4 , 12 , 28 , 28 , 32 , 32 , 32
Deflcdchar 2 , 32 , 4 , 14 , 31 , 31 , 32 , 32 , 32
Deflcdchar 3 , 32 , 4 , 14 , 31 , 31 , 7 , 6 , 4
Deflcdchar 4 , 32 , 4 , 14 , 31 , 31 , 31 , 14 , 4
Deflcdchar 5 , 32 , 32 , 32 , 32 , 32 , 32 , 32 , 32
Dim A As Word
Dim B As Word
Dim C As Single
Dim D As Byte
D = 1
Start Adc
Cursor Off
Cls
Locate 2 , 1
Lcd "avrprojects.info"
Do
A = Getadc(3)
B = Getadc(4)
C = A - B
C = C / 4
Locate 1 , 1
Lcd "Temp =" ; C ; Chr(0) ; "c   "
Locate 1 , 16
Lcd Chr(d)
Waitms 500
Incr D
If D > 6 Then D = 1
Loop
End

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