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6.4 Pin Assignment & Laser Marking

Pin

Name

Comments

1

SDA

Serial data, bidirectional

RH out

2

SCL

Serial clock,

unidirectional input

T out

3

VDD

Supply voltage

4

VSS

Ground

Figure 8. Pin assignment (transparent top view). Dashed lines are only visible if the sensor is viewed from

below. The die pad is not directly connected to any pin.

The laser marking consists of two lines, indicated in Figure 13. In the first line a filled circle serves as pin-1

indicator and is followed by “SH41A”. “A” indicates the automotive grade. In the second line, the first three

characters specify the product characteristics according to positions 8, 9 and 10 of Table 11. The last three

characters serve as internal batch tracking code.

6.5 Thermal Information

Symbol

Description

Heater off, die

pad soldered

(K/W)

Heater on, die

pad soldered

(K/W)

Heater off,

die pad

not soldered

(K/W)

Heater on,

die pad

not soldered

(K/W)

DFN

DFN+WF

DFN

DFN+WF

DFN

DFN+WF

DFN

DFN+WF

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Junction-to-

ambie.

thermal

resistance

246

258

308

329

297

322

357

390

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Junction-to-

case thermal

resistance

189

183

255

252

191

188

257

254

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Junction-to-

board thermal

resistance

159

177

225

242

193

219

258

284

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Junction-to-

board

characteriz.

param.

159

171

223

242

191

213

254

282

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Junction-to-

top

characteriz.

param.

38

35

105

104

44

42

112

111

Table 11. Typical values for thermal metrics. In the “heater on” columns a heater power of 200 mW was assumed.

Soldering the die pad is not recommended, therefore the two right hand side columns are bold. The sub-

columns labelled “DFN+WF” display the results for the DFN package with soldered wettable flanks terminals.

Values are based on simulation.