DA6512.000

11 July, 2012

10 (26)

This register is used to configure and initiate a

measurement. See table 3 below. A new conversion

is started simply by writing 8-bit configuration data

Table 3.

Bit Number

Bit Name

Description

Value

Function

7-5

OSRS

Over Sampling Ratio

(OSR) Selection

000

001

010

011

100

OSR = 256

OSR = 512

OSR = 1024

OSR = 2048

OSR = 4096

4

REGEN

Regulator Enable

0

1

Voltage regulator disabled

Voltage regulator enabled

3

SCO

Start Conversion

0

1

No conversion

Start conversion

2

XETS

Sensor Selection

0

1

External capacitive sensor

Internal temperature sensor

1

-

Not used

-

-

0

XRC

Front end function

selector

0

1

Ratio converter

Difference converter

The OSRS over sampling ratio selection bits

choose between five different OSR values. High

OSR value corresponds to high resolution but also

longer

conversion

time.

See

Electrical

characteristics for further details.

The REGEN bit enables/disables the internal

voltage regulator. When enabled the regulator is

turned on during conversions and automatically

turned off after each conversion to save power.

During temperature measurements the regulator is

always enabled regardless of the REGEN bit

setting. Note that if Test register FOSC=1 and if

REGEN=1 the regulator is forced on all the time

independently of measurements.

The SCO Start conversion bit needs to be set 1 for

every new measurement. It is automatically reset to

0 after each measurement.

The XETS Sensor selection bit controls the front-

end multiplexer and connects either the external

capacitive

sensor

(XETS=0)

or

the

internal

temperature sensor (XETS=1) to the ∆Σ-converter.

The

XRC

bit

selects

between

two

external

capacitive sensor measurement modes. It does not

have any effect on temperature measurement. In

Ratio converter mode the measured value will be

Difference converter mode the measurement will be