BMA253
Data sheet
Page 96
7. Digital interfaces
The BMA253 supports two serial digital interface protocols for communication as a slave with a
host device (when operating in general mode): SPI and I²C. The active interface is selected by
the state of the Pin#11 (PS) ‘protocol select’ pin: ´0´ (´1´) selects SPI (I²C). For details please
refer to section 8).
By default, SPI operates in the standard 4-wire configuration. It can be re-configured by
software to work in 3-wire mode instead of standard 4-wire mode.
Both interfaces share the same pins. The mapping for each interface is given in the following
table:
Table 20: Mapping of the interface pins
use w/ use w/
Pin# Name
Description
SPI
I²C
SPI: Data Output (4-wire mode)
I²C: Used to set LSB of I²C address
1
2
SDO
SDx
SDO
address
SPI: Data Input (4-wire mode) Data Input / Output (3-wire
SDI
SDA
mode)
I²C: Serial Data
10
12
CSB
SCx
CSB
SCK
unused
SCL
Chip Select (enable)
SPI: Serial Clock
I²C: Serial Clock
The following table shows the electrical specifications of the interface pins:
Table 21: Electrical specification of the interface pins
Parameter
Symbol
Rup
Condition
Min
Typ
100
5
Max
125
10
Units
k
Internal Pull-up
Resistance to
VDDIO
Pull-up Resistance,
CSB pin
75
Input Capacitance
Cin
pF
I²C Bus Load
Capacitance (max.
drive capability)
CI2C_Load
400
pF
BST-BMA253-DS000-01 | Revision 1.0 | August 2015
Bosch Sensortec
© Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to
third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Note: Specifications within this document are subject to change without notice.
BOSCH [ Bosch Sensortec GmbH ]
