1.0 LM94021 Transfer Function

(Continued)

The output voltages in this table apply for V

Temperature

(˚C)

GS=00

(mV)

GS=01

(mV)

GS=10

(mV)

GS=11

(mV)

130

302

478

653

829

131

296

469

642

814

132

291

460

630

800

133

285

452

618

786

134

279

443

607

771

135

273

434

595

757

136

267

425

584

742

137

261

416

572

728

138

255

408

560

713

139

249

399

549

699

140

243

390

537

684

141

237

381

525

670

142

231

372

514

655

143

225

363

502

640

144

219

354

490

626

145

213

346

479

611

146

207

337

467

597

147

201

328

455

582

148

195

319

443

568

149

189

310

432

553

150

183

301

420

538

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.

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