LM80CIMTX-3 National Semiconductor, LM80CIMTX-3 Datasheet - Page 16

• Manufacturer Part Number: LM80CIMTX-3
• Manufacturer: National Semiconductor

Specifications of LM80CIMTX-3

• Battery Backup Switching: No
• Watchdog Timer: Yes
• Chip Enable Signals: No
• Manual Reset: No
• Package Type: TSSOP
• Operating Supply Voltage (min): 2.8V
• Operating Supply Voltage (max): 5.75V
• Operating Temp Range: -25C to 125C
• Operating Temperature Classification: Commercial
• Power Fail Detection: No
• Mounting: Surface Mount
• Pin Count: 24
• Lead Free Status / Rohs Status: Not Compliant

www.national.com
(Non-Linear Scale for Clarity)
7.1 Temperature Data Format
Temperature data can be read from the Temperature, T
T
T
ters are located in register addresses 38h - 3Bh, and each
setpoint is represented by an 8-bit, two's complement word
with an LSB (Least Significant Bit) equal to 1°C:
By default Temperature Register data is represented by a 9-
bit two's complement digital word with the LSB having a
resolution of 0.5°C:
hot hyst
hot
Temperature
Temperature
, T
hot hyst
+125°C
+125°C
+1.0°C
−1.0°C
+1.5°C
−0.5°C
+25°C
−25°C
−55°C
+25°C
−25°C
−55°C
, T
+0°C
+0°C
os
, T
and T
os
and T
os hyst
os hyst
setpoint registers; and written to the
0 1111 1010
0 0011 0010
0 0000 0011
0 0000 0000
1 1111 1111
1 1100 1110
1 1001 0010
0111 1101
0001 1001
0000 0001
0000 0000
1111 1111
1110 0111
1100 1001
Binary
Binary
setpoint registers. These regis-
Digital Output
Digital Output
FIGURE 9. 12-bit Temperature-to-Digital Transfer Function
0 FAh
1 CEh
1 FFh
0 32h
0 03h
0 00h
1 92h
Hex
7Dh
C9h
Hex
FFh
E7h
19h
01h
00h
hot
,
16
Temperature Register data can also be represented by a 12-
bit two's complement digital word with a LSB of 0.0625°C:
The 8 MSBs of the Temperature reading can be found at Val-
ue RAM address 27 h. The remainder of the Temperature
reading can be found in the OS Configuration/Temperature
Resolution Register bits 7-4. In 9-bit format bit 7 is the only
valid bit.
Temperature
+0.0625°C
−0.0625°C
+125°C
+1.0°C
−1.0°C
+25°C
−25°C
−55°C
0°C
0111 1100 0000
0001 1001 0000
0000 0001 0000
0000 0000 0001
0000 0000 0000
1111 1111 1111
1111 1111 0000
1110 0111 0000
1100 1001 0000
10004016
Binary
Digital Output
7 D0h
F FFh
C 90h
1 90h
0 10h
0 01h
F F0h
E 70h
Hex
00h