DA6503.005
14 December 2016
APPLICATION INFORMATION
VDD rise time < 1ms
CVDD
CVREG
VDD
VDD
VDD
470pF
1.0µF
RP
4.7k
TE3
OSC
VDD
VREG
VDD
RP
4.7k
EEPROM
VREFP
ADC
PI
NI
P
T
SDA/MOSI
SENSOR
I/O
I/O
I2C/
SPI
MISO
CONTROL
P
SCL/SCLK
XCS
T
VDD
VDD
COMMON
R3
VREFN
XCLR
EOC
XSPI
R1
I/O
I/O
OPTIONAL
VDD
R4
R2
TEST
MAS6503
T
P
T
MCU
TE1 TE2
GND
GND
GND
GND
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.
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 1F 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.
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MAS [ MICRO ANALOG SYSTEMS ]
