lm94021-mda National Semiconductor Corporation, lm94021-mda Datasheet - Page 9

• Manufacturer Part Number: lm94021-mda
• Description: Multi-gain Analog Temperature Sensor
• Manufacturer: National Semiconductor Corporation

1.0 LM94021 Transfer Function
LM94021 Transfer Table
(Continued)
The output voltages in this table apply for V
Temperature
(˚C)
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
GS = 00
(mV)
302
296
291
285
279
273
267
261
255
249
243
237
231
225
219
213
207
201
195
189
183
GS = 01
(mV)
478
469
460
452
443
434
425
416
408
399
390
381
372
363
354
346
337
328
319
310
301
GS = 10
(mV)
653
642
630
618
607
595
584
572
560
549
537
525
514
502
490
479
467
455
443
432
420
(Continued)
DD
= 5V.
GS = 11
(mV)
829
814
800
786
771
757
742
728
713
699
684
670
655
640
626
611
597
582
568
553
538
9
Although the LM94021 is very linear, its response does have
a slight downward parabolic shape. This shape is very ac-
curately reflected in the LM94021 Transfer Table. For a
linear approximation, a line can easily be calculated over the
desired temperature range from the Table using the two-
point equation:
Where V is in mV, T is in ˚C, T
of the lowest temperature, T
the highest temperature.
For example, if we want to determine the equation of a line
with the Gain Setting at GS1 = 0 and GS0 = 0, over a
temperature range of 20˚C to 50˚C, we would proceed as
follows:
Using this method of linear approximation, the transfer func-
tion can be approximated for one or more temperature
ranges of interest.
2
and V
1
and V
2
are the coordinates of
1
are the coordinates
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