Application hints LIS244AL
10/15
4 Application hints
Figure 3. LIS244AL Electrical connection
Power supply decoupling capacitors (100nF ceramic or polyester + 10µF Aluminum) should
be placed as near as possible to the device (common design practice).
The LIS244AL allows to band limit Voutx, Vouty through the use of external capacitors. The
recommended frequency range spans from DC up to 2.0kHz. In particular, capacitors are
added at output Voutx, Vouty pins to implement low-pass filtering for antialiasing and noise
reduction. The equation for the cut-off frequency (f
t
) of the external filters is in this case:
Equation 1
Taking into account that the internal filtering resistor (R
out
) has a nominal value equal to
32kΩ, the equation for the external filter cut-off frequency may be simplified as follows:
Equation 2
Digital signals
LIS244AL
(top view)
(TOP VIEW)
DIRECTION OF THE
DETECTABLE
ACCELERATIONS
Y
1
X
ST
GND
1
4
9
12
Vdd
GND
GND
100nF
10
µ
F
Vout y
Optional
Cload y
Vout x
Cload x
Optional
5
16
2
3
67
8
10
11
15 14 13
Pin 1 indicator
f
t
1
2π R
out
C
load
xy,()⋅⋅
----------------------------------------------------------------=
f
t
5µF
C
load
xy,
--------------------------
Hz[]=
Obsolete Product(s) - Obsolete Product(s)
