DA6512.003
2 December, 2016
MEASUREMENT CONTROL REGISTER (E2/62HEX
)
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
having SCO=1 to the measurement control register
(E2/62HEX).
Table 3. Measurement control register (E2/62HEX) description
Bit Number
Bit Name
Description
Value
Function
7-5
OSRS
Over Sampling Ratio
(OSR) Selection
000
001
010
011
0
1
0
OSR = 256
OSR = 512
OSR = 1024
OSR = 2048
4
3
TEMPREGEN
SCO
Temperature Mode
Regulator Enable
Start Conversion
Voltage regulator disabled
Voltage regulator enabled
No conversion
1
Start conversion
External capacitive sensor
VDD level monitoring
Internal temperature sensor
-
2-1
SEL
Capacitive/ VDD
Monitoring /
00
01
10
11
0
Temperature Selection
0
XRC
Front end function
selector
Ratio converter
1
Difference converter
The OSRS over sampling ratio selection bits
choose between four different OSR values. High
OSR value corresponds to high resolution but also
The SCO Start conversion bit needs to be set 1 for
every new measurement. It is automatically reset to
0 after each measurement.
longer
conversion
time.
See
Electrical
The SEL sensor selection bits control the front-end
multiplexer. It connects either the external
capacitive sensor (SEL=00), VDD level monitoring
voltage (SEL=01) or the internal temperature sensor
(SEL=10) to the -converter.
characteristics for further details.
The TEMPREGEN bit enables/disables the internal
temperature mode voltage regulator. The regulator
need to be enabled (TEMPREGEN=1) only in
temperature mode and it should be disabled
(TEMPREGEN=0) in capacitance and VDD
monitoring modes. When enabled the regulator is
turned on during conversions and automatically
turned off after each conversion to save power.
Note also that if in Test register FOSC=1 and if
TEMPREGEN=1 the regulator is forced on all the
time even when measurement is not running.
The XRC bit selects between two external
capacitive sensor measurement modes. The XRC
bit selection does not have any effect on
temperature
or
VDD
level
monitoring
measurements. In Ratio converter mode the output
will be proportional to capacitance ratio (CS-CR)/CS.
In Difference converter mode the output will be
proportional to capacitance difference (CS-CR).
12 (32)