DA6512.000

11 July, 2012

8 (26)

REGISTER AND EEPROM DATA ADDRESSES

MAS6512 includes a 32 bytes (256 bits) EEPROM

data memory and eleven registers. Four bytes (32

bits) of EEPROM are reserved for trim values but

the remaining 28 bytes (224 bits) are free for storing

sensor calibration and other data. See table 1 on

the previous page for register and EEPROM data

addresses.

In the SPI serial bus the address bit A7 selects

between write (A7=0) and read (A7=1) operation. In

the I

selection between write and read operation is done

with the LSB bit of the I

6 in chapter 2-WIRE SERIAL DATA INTERFACE

(I

MAS6512 has four trim registers: CS capacitor

marked with “R+T” in table 1. Each of these

registers has a corresponding EEPROM byte where

trim values can be permanently stored. These are

marked with “E+T” in table 1. Trim values are

automatically read from EEPROM in the beginning

of each conversion when this feature is enabled in

disabled it is possible to test different trim data in

the trim registers before final trimming values are

found and stored in the EEPROM.

Any dummy data written to this register forces a

reset.

A

reset

initializes

all

control

registers

and trimming purposes. See table 2 in chapter

TEST REGISTER. If an external clock signal is

used the test register is needed for selecting the

external clock signal.

used for configuring and starting an A/D conversion.

matrix registers contain a capacitor value between 0

and 22pF in 86fF steps.

CDC front-end. Together with the CS and CR

values

it

determines

the

input

capacitance

conversion range.

is used only during internal clock oscillator trimming.

During trimming this register value is iterated to give

the desired 200kHz oscillator frequency. When the

best value is found it can be written to the internal

clock

oscillator

frequency

trimming

EEPROM

value is automatically read from the EEPROM

memory in the beginning of each conversion. The

clock frequency is trimmed by MAS during wafer

level testing and there should be no need to modify

it.

The 16-bit A/D conversion result (capacitance or

significant byte).

the EEPROM error correction status. This register

can be used to verify that the EEPROM operation

has finished without errors.

the trim data in the EEPROM or in the registers are

used

during operation. The Trimming control

register is also used for enabling EEPROM write.

The

default

setting

is

that

all trim

data is

automatically read from the EEPROM memory in

the beginning of each conversion and that the

EEPROM write is disabled. See the Trimming

control register description for details.