www.sensirion.com / D1

Version 1

– October 2020

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5.4 Pin Assignment & Laser Marking

Pin

Name

Comments

1

SDA

Serial data, bidirectional

2

SCL

Serial clock, unidirectional input

3

VDD

Supply voltage

4

VSS

Ground

Figure 11 Pin assignment (transparent top view). Dashed lines are only visible if 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 11. In the first line a filled circle serves

as pin-1 indicator

and is followed by “SH4”. The last character will indicate the accuracy class of

this product (here “x” serves as place holder). In the second line, the first three characters specify

the product characteristics according to positions 7,8 and 9 of Table 9. The second three

characters serve as internal batch tracking code.

5.5 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)

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Junction-to-ambient

thermal resistance

246

308

297

357

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Junction-to-case

thermal resistance

189

255

191

257

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Junction-to-board

thermal resistance

159

225

193

258

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Junction-to-board

characterization

param.

159

223

191

254

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Junction-to-top

characterization

param.

38

105

44

112

Table 8 Typical

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

assumed. Soldering of the die pad is not recommended, therefore the two right hand side columns are bold.

Values are based on simulation.

6 Quality and Material Contents

Qualification of SHT4x is performed based on the JEDEC JESD47 qualification test method.

Qualification pending. The device is fully RoHS and WEEE compliant, e.g. free of Pb, Cd, and

Hg.

For general remarks of best practice in processing humidity sensor please refer to the handling

instructions (Sensirion, 2020).

7 Tape and Reel Packaging

All specifications for the tape and reel packaging can be found on Figure 12. Reel diameters are

13 inch and 8 inch for the 10k and the 2.5k packaging sizes, respectively.