SCA8X0/21X0/3100 Series
2.4 Power Down mode
For low power applications it is possible to set the accelerometer into power down mode. During
the power down mode the power consumption is minimized inside the device. This is achieved by
stopping the internal clocks and resetting the control registers of the device. Please refer to the
individual device data sheets for detail power consumption figures.
2.5 Recommended start-up sequence
For correct device operation there are no specific configuration needed for the device before
starting of measuring the acceleration. However if the device detail features are being used the
following operations could be made after the powering on the device.
Table 2: SCA8X0 start up sequence
Item
1
Procedure
Set Vdd=3.0...3.6V
Functions
Check
-
•
Set the
power on to
release part
from reset
and to start
the operation
During the
first 95ms the
part is
2
Wait 95ms
-
•
performing
the memory
read and self-
diagnostics.
Possible
•
signal path
self-
diagnostic
test is carried
out.
•
•
Settling of
signal path
Check the
self-test pass
status
Check the
memory
checksum
pass status
3
4
Read CTRL-register
•
•
•
•
•
•
•
•
•
CTRL.ST=0
SPI fixed bits
dPAR, data parity
STATUS.CSMERR=0
SPI fixed bits
SPI FRME=0
dPAR, data parity
SPI fixed bits
Read STATUS-register
•
•
5
Write CTRL=0000 0000
After device
power on set
PORST=0 to
be able to
detect any
future
SPI FRME=0
occurring
power
failures
6
Read X_MSB, X_LSB –
registers
•
Start reading
the
acceleration
data
•
•
•
•
SPI fixed bits
SPI FRME=0
SPI PORST=0
dPAR, data parity
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