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Version 3 – August 2020

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5 Packaging

The SHT85 is supplied in a single-in-line pin type package. The SHT35-DIS sensor housing consists of an epoxy-based

mold compound, see “Datasheet SHT3x-DIS” for more information. The sensor opening of the housing is protected by a

PTFE membrane dedicated to protect the sensor opening from liquids and dust according to IP67, see “Datasheet

Membrane Option” for more information. The sensor head is connected to the pins by a small bridge to minimize heat

conduction and response times. The pins are soldered to the FR4 substrate by lead-free solder paste. The gold plated

backside of the sensor head is connected to the VSS pin. A 100nF capacitor is mounted on the front side between VDD

and VSS. The device is fully RoHS compliant – thus it is free of of Pb, Cd, Hg, Cr(6+), PBB and PBDE. All pins are Au

plated to avoid corrosion. They can be soldered or mate with most 1.27 mm (0.05’’) sockets, for example: Preci-Dip 851-

87-004-10-001101 / 851-87-004-20-001101, Harwin M50-3030442 or similar. Solder joints and contacts are protected

by conformal coating material on front and back side. When the sensor is further processed by soldering, it should be

ensured that the solder connections between pins and the SHT85 PCB are not melted.

5.1 Traceability

The SHT85 provides a device specific serial number, which can be read-out via the serial interface (I2C), see the

command in Table 21. The Serial number allows an unambiguous identification of each individual device.

Command

Hex Code

Get Serial Number

0x 36 82

Table 21: Command to read out the Serial Number (Clear blocks are controlled by

the microcontroller, grey blocks by the sensor.)

The Get Serial Number command returns 2 words; every word is followed by a CRC Checksum. Together the 2 words

(SNB_3 to SNB_0 in Table 21, SNB_0 is the LSB, whereas SNB_3 is the MSB) constitute a unique serial number with

a length of 32 bit. This serial number can be used to identify each sensor individually.

t

IDLE

9

36

SNB_3

SNB_2

CRC

Serial Number Word 1

Checksum

37

63

SNB_1

SNB_0

CRC

Serial Number Word 2

Checksum

P

SNB_3

I2C Address

Command MSB

Command LSB

16-bit command

16-bit command

I2C write header

I2C read header

I2C Address

S

W

S

R

1

2

3

4

5

6

7

8

9

10 11 12 13 14 15 16 17 18 19 20 21 22 23

24 25 26 27

1

2

3

4

5

6

7

8

9