ASM330LHH
7 Application hints
7.1 ASM330LHH electrical connections
Figure 14. ASM330LHH electrical connections
Application hints
The device core is supplied through the Vdd line while the I/O pads are supplied through the
Vdd_IO line. As a common design practice, the power supply decoupling capacitors
C1 = 100 nF ceramic and C2 =10 μF aluminum should be placed as near as possible to pin 8, while C3 = 100 nF ceramic should be positioned as close as possible to pin 5.
All the voltage and ground supplies must be present at the same time to have proper IC behavior.
The functionality of the device and the measured acceleration/angular rate data are selectable and accessible through the I²C or SPI interfaces. When using the I²C protocol,
CS must be tied high. Every time the CS line is set to low level, the I²C bus is internally reset.
All the functions, the threshold and the timing of the two interrupt pins can be completely programmed by the user through the I²C/SPI interface.
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Application hints ASM330LHH
The procedure to correctly initialize the device is as follows:
1.
INT1: Leave unconnected or connect with external pull-down during power-on. Pull-up must be avoided on this pin.
2. INT2: Recommended to not connect with external pull-up.
3. Properly configure the device: a) SPI case: I2C_disable = 1 in
CTRL4_C (13h) and DEVICE_CONF = 1 in
CTRL9_XL (18h)
. b) I²C case: I2C_disable = 0 (default) in
CTRL4_C (13h)
and DEVICE_CONF = 1 in
CTRL9_XL (18h)
. pin# Name
Table 17. Internal pin status
Function Pin status
1
7
8
5
6
2
3
4
9
10
11
12
13
14
SDO
SA0
RES
RES
INT1
VDDIO
GND
GND
VDD
INT2
NC
NC
CS
SCL
SDA
SPI 4-wire interface serial data output
(SDO)
I²C least significant bit of the device address (SA0)
Connect to VDDIO or GND
Connect to VDDIO or GND
Programmable interrupt 1
Power supply for I/O pins
0 V supply
0 V supply
Power supply
Programmable interrupt 2 (INT2) / Data enabled (DEN)
Leave unconnected
Leave unconnected
I²C/SPI mode selection
(1:SPI idle mode /
I²C communication enabled;
0: SPI communication mode /
I²C disabled)
I²C serial clock (SCL) /
SPI serial port clock (SPC)
I²C serial data (SDA) /
SPI serial data input (SDI) /
3-wire interface serial data output (SDO)
Default: input without pull-up.
Pull-up is enabled if bit SDO_PU_EN = 1 in reg. 02h.
Default: input without pull-up.
Default: input without pull-up.
Default: input with pull-down
(1)
Default: output forced to ground
Default: input with pull-up.
Default: input with pull-up.
Default: input with pull-up.
Pull-up is disabled if bit I2C_disable = 1 in reg 13h and DEVICE_CONF = 1 in reg 18h.
Default: input without pull-up
Default: input without pull-up
1. INT1 must be set to '0' or left unconnected during power-on.
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