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Version 0.8 – January 2017

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3. Pin Assignment

The SDP3x consists of a QFN package with a plastic cap covering the top and providing the pneumatic connections to the

sensor. The pin assignments of the SDP3x-Digital can be found in Table 1.

Pin no.

Name

Description

1

GND

Connect to ground

2

GND

Connect to ground

3

GND

Connect to ground

4

IRQn

Interrupt output. Active low. Keep

floating when not used.

5

SCL

Serial Clock (I2C Interface)

6

GND

Connect to ground

7

VDD

VDD Supply

8

SDA

Bidirectional Serial Data (I2C Interface)

9

ADDR

I2C Address selection input.

10

GND

Connect to ground

11

GND

Connect to ground

12-16

-

Reserved. Do not connect

Table 1: SDP3x-Digital pin assignment (bottom view).

3.1

Power Pins (VDD, GND)

The power supply pins must be decoupled with a 100 nF capacitor that shall be placed as close to the sensor as possible.

3.2

Serial Clock and Serial Data (SCL, SDA)

The SCL and SDA are bidirectional pins of the I2C slave interface. The SCL is the Serial Clock pin and the SDA is the Serial

Data pin. For more details about the I2C interface refer to section 5.

3.3

ADDR Pin

The SDP3x-Digital supports different I2C addresses. With the ADDR pin an address can be selected. Connecting the ADDR

pin to GND selects the default address. Other I2C addresses can be selected with a resistor connected to GND. The maximum

tolerance for the resistor is ±5%. Do not connect the ADDR pin to VDD.

I2C Address (Hex) Condition

0x21

ADDR connected to GND

0x22

ADDR connected with 1.2kOhm to GND

0x23

ADDR connected with 2.7kOhm to GND

3.4

IRQn Pin

The IRQn pin indicates whether new measurement results are available. The signal is active low, meaning that when the

signal is high there is no new measurement data available. The IRQn will automatically clear to high when a differential

pressure value is read out. The IRQn pin will also be set to low after every soft reset or Power on Reset, until a measurement

command is sent.

When the IRQn signal is not used, the pin should stay unconnected and must not be connected to GND or VDD.

3.5

Die Pad (Center Pad)

The die pad or center pad is visible from below and located in the center of the package. It is internally connected to GND and

therefore there are no electrical constraints on connecting or not connecting the die pad to GND. For mechanical stability it is

recommended to solder the center pad to the PCB.

The hole in the middle of the die pad must stay open during soldering.