Datasheet

Bosch Sensortec
| BMI088 Data sheet
32 |
48
Modifications reserved | Data subject to change without notice
Document number: BST-BMI088-DS001-1
3
Revision_1.3_05201
8
6. Digital Interface
The BMI088 supports two serial digital interface protocols for communication as a slave with a host
device: SPI and I²C. The active interface is selected by the state of the Pin#07 (PS) ‘protocol select’ pin:
• PS = ´VDDIO´ selects I²C
• PS = ´GND´ selects SPI
Important:
• Please note that in case of SPI protocol the initialization process for the accelerometer part of
BMI088 requires some additional steps (see chapter 3).
• Please also note that as the pins of the package are shared between accelerometer and
gyroscope part, it is not advisable to configure different interfaces for the two parts.
Both digital interfaces share partly the same pins. Additionally each inertial sensor (accelerometer and
gyroscope) provides specific interface pins, which allow the user to operate the inertial sensors
independently of each other. The mapping for each interface and each inertial sensor is given in the
following table:
Table 10: Mapping of the interface pins
Pin#
Name
use w/
SPI
use w/
I²C
Description
15
SDO1
SDO1
address
SPI: Accel Data Output
I²C: Used to set LSB of Accel I²C address
10
SDO2
SDO2
address
SPI: Gyro Data Output
I²C: Used to set LSB of Gyro I²C address
9 SDA /
SDI
SDI SDA SPI: Accel and Gyro Data In
I²C: Serial Data
14
CSB1
CSB1
unused
SPI: Accel Chip Select (enable)
5
CSB2
CSB2
unused
SPI: Gyro Chip Select (enable)
8
SCL /
SCK
SCK
SCL
SPI: Serial Clock SCK
I²C: Serial Clock SCL
The following table shows the electrical specifications of the interface pins:
Table 11: Electrical specification of the interface pins
Parameter
Symbol
Condition
Min
Typ
Max
Units
Pull-up Resistance,
CSB pin
R
up
Internal Pull-up
Resistance to
VDDIO
75
100
125
k
Input Capacitance
C
in
5
10
pF
I²C Bus Load
Capacitance (max.
drive capability)
C
I2C_Load
400 pF