DA6503.005
14 December 2016
REGISTER AND EEPROM DATA ADDRESSES
MAS6503 includes a 32 bytes (256 bits) EEPROM
data memory and twelve registers. Two bytes (16
bits) of EEPROM are reserved for internal 500 kHz
oscillator frequency trim and programmable I2C
device address data but the remaining 30 bytes
(240 bits) are free for storing sensor calibration and
other data. See table 1 on the previous page for
register and EEPROM data addresses.
Test register (E1/61HEX) is mainly used for testing
and trimming purposes. It defines whether the
internal oscillator frequency trim data is taken from
the EEPROM (default setting) or from the registers.
However if an external clock signal is used the test
register is needed for selecting the external clock
signal. See the Test register description for details.
There are two Measurement control registers, first
(E2/62HEX) and second (E3/63HEX) which are used
for configuring and starting an A/D conversion.
In the SPI serial bus the address bit A7 selects
between write (A7=0) and read (A7=1) operation. In
the I2C serial bus A7 is always high (A7=1) and
selection between write and read operation is done
with the LSB bit of the I2C device address. See
table 9 in chapter SERIAL DATA INTERFACE
CONTROL. The MAS6503 has both hard wired and
programmable I2C device addresses. The
The Oscillator frequency control register (E4/64HEX
)
is used only during internal clock oscillator
trimming. During trimming there is searched
register value which gives closest to the nominal
500 kHz oscillator frequency. However the internal
clock oscillator frequency is trimmed by MAS during
wafer level testing and the trimming value is stored
into the Oscillator frequency trim data EEPROM
address (DF/5FHEX). Thus there is no need to adjust
the factory stored clock oscillator trimming value. In
normal operation the trim value is automatically
read from the EEPROM memory in the beginning of
each conversion.
programmable
device
address
is
factory
programmed to value EA HEX (%11101010) which is
the same as the hard wired device address of
MAS6503. When unique device address is needed
it can be programmed to the Programmable I2C
Device Address register (DEHEX/5EHEX). The
MAS6503 will respond to both hard wired and
programmed I2C device addresses.
EEPROM write enable register (E6/66HEX) is used
for enabling EEPROM write (EWE bit = 1) since by
default the EEPROM is write protected (EWE bit =
0).
MAS6503 has one trim register: Oscillator
frequency control register (E4/64HEX). This is
marked with “R+T” in table 1. In the EEPROM there
is specific Oscillator frequency trim data address
(DF/5FHEX) reserved for permanent storage of the
trim value. This is marked with “E+T” in table 1. The
internal 500 kHz oscillator frequency trim value is
automatically read from EEPROM in the beginning
of each conversion when this feature is enabled in
the Test register (E1/61HEX). When disabled it is
possible to test different trim data in the trim
registers before trimming value is found and stored
into the EEPROM. Note that Oscillator frequency
trim value has been factory calibrated and stored
into the EEPROM.
The 24-bit A/D conversion result (sensor,
temperature or VDD level) is stored into three
registers E8HEX (MSB, most significant byte), E9HEX
(ISB, intermediate significant byte), EAHEX (LSB,
least significant byte).
EEPROM status register (EA/6AHEX) reflects the
EEPROM error correction status. This register can
be used to verify that the EEPROM operation has
finished without errors.
Regulator output voltage control register (EB/6BHEX
)
defines regulator output voltage when the internal
regulator is enabled.
Reset register (E0/60HEX) does not contain any
data. Any dummy data written to this register forces
a reset. A reset initializes all control registers
(addresses E1HEX…EBHEX) to a zero value.
12 (34)