Information

BMA280
Data sheet
Page 96
BST-BMA280-DS000-11 | Revision 1.8 | August 2014 Bosch Sensortec
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Note: Specifications within this document are subject to change without notice.
7. Digital interfaces
The BMA280 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
Pin#
Name
use w/
SPI
use w/
I²C
Description
1
SDO
SDO
address
SPI: Data Output (4-wire mode)
I²C: Used to set LSB of I²C address
2
SDx
SDI
SDA
SPI: Data Input (4-wire mode) Data Input / Output (3-wire
mode)
I²C: Serial Data
10
CSB
CSB
unused
Chip Select (enable)
12
SCx
SCK
SCL
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
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