UM-B-077
DA14681 Wearable Development Kit Hardware Manual
User Manual
Revision 1.2
06-Apr-2017
CFR0012
22 of 47
© 2017 Dialog Semiconductor
4.6
DA14681 Wearable Reference Design Sensors
The wearable reference design consists of the following sensor components from Bosch SensorTec:
●
BMI160
: Combined Inertial Measurement Unit and Accelerometer
●
BMM150
: Magnetometer
●
BME280
: Environmental Sensor
●
BH1750FVI
: Ambient Light Sensor
4.6.1
BMI160 - Combined Inertial Measurement Unit and Accelerometer
The BMI160 is a low-power, low-noise inertial measurement unit, designed for use in mobile and
indoor applications which require highly accurate, real-time sensor data. In full operation mode, with
the accelerometer and gyroscope enabled, the current consumption is typically 950
A, while this is
dropped down to 3
A is suspend mode.
The BMI160 module is connected to the DA14681 via an SPI interface. In this reference design the
secondary I2C interface of the BMI160 is used to connect the BMM150 (magnetometer) to the
BMI160 in slave mode, in order to acquire the data in synchronized form. This configuration is called
cascade mode
and minimizes the number of the GPIOs needed as well as the processor resources.
Figure 17: BMI160- Inertial Sensor Schematic
Table 9: BMI160 Inertial Sensor - Electrical Characteristics
Parameter
Min
Typ
Max
Unit
Supply Voltage (VDD)
1.71
3.0
3.6
V
Supply Voltage (VDD I/O)
1.2
2.4
3.6
V
Voltage Input Low Level
0.3*VDD I/O
V
Voltage Input High Level
0.7*VDD I/O
V
Voltage Output Low Level
0.2*VDD I/O
V
Voltage Output High Level
0.23*VDD I/O
V
Operating Temperature
-40
85
°C
SDX
SCX
CSB
U2
BMI160
SDO
1
ASDx
2
ASCx
3
INT1
4
VD
D
IO
5
GN
D
IO
6
GN
D
7
VDD
8
INT2
9
OSCB
10
OSDO
11
C
SB
12
SC
X
13
SD
X
14