DA6503.005

14 December 2016

28 (34)

APPLICATION INFORMATION

VDD rise time < 1ms

Figure 11. Typical application circuit configured for I2C bus communication

Figure 11 presents MAS6503 application circuit using I2C bus and when VDD rise time is guaranteed to be

always below internal POR circuit delay of 1ms. In case the VDD rise time can exceed 1ms see the next page

application information.

Together with a resistive pressure sensor, MAS6503 can be used in pressure measurement applications. An

external micro-controller can control the MAS6503 via an I2C or a SPI serial interface. Note that the I2C serial

interface requires suitable pull-up resistors connected to the SDA and SCL pins (see figure 11). If there is only a

single master device connected to the serial bus the master’s SCL output can be of push-pull type making the

SCL pull-up resistor unnecessary.

The sensor is connected between voltage regulator output (VREG) and grounding switch (COMMON) of

MAS6503. The sensor output is read as a differential signal through PI (positive input) and NI (negative input) to

the ΔΣ converter in MAS6503.

When using the internal regulator a 470pF capacitor should be connected between the regulator output VREG

and GND and a decoupling capacitor of minimum 1

F should be used for the supply voltage VDD (see figure

11). If the internal regulator is disabled a supply voltage decoupling capacitor of 4.7

F or more should be

placed between VDD and GND to guarantee conversion accuracy.

GND

R2

R4

R1

R3

ADC

PI

NI

COMMON

VDD

P

T

P

T

P

T

T

GND

VREG

CONTROL

SENSOR

VREFN

VREFP

TEST

I2C/

SPI

OSC

EEPROM

SDA/MOSI

SCL/SCLK

TE3

EOC

XCLR

TE1

TE2

MAS6503

470pF

VDD

MISO

XCS

XSPI

VDD

C

VDD

1.0µF

NOTE: It is recommended to use the XCLR reset feature to solve unexpected error state conditions. In case VDD rise time can

exceed 1ms the device has to be kept in a reset during power up by using the XCLR pin. Violating this may risk EEPROM integrity.

If not used the XCLR pin can be left unconnected since it has internal pull up to VDD.

VDD

MCU

I/O

I/O

I/O

I/O

GND

GND

VDD

VDD

OPTIONAL

VDD

4.7k

4.7k

VDD