Data Sheet

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SPI Communication
Output edge rise time
Or
3
ns
Output edge fall time
Of
3
ns
4.2 Read/Write Access
Data is transferred to the device via the MOSI pin with the rising edge of SCK. It should be updated by
the master at the falling edge of SCK.
Data is updated at the MISO pin with the falling edge of SCK and can safely be read from the device with
the rising edge of SCK.
The data format consists of data streams with 32 bit in length. The first 16 bits define a 16-bit address and
the subsequent 16 bits contain read or write data.
The MSB of the address word A<15> defines the direction of data transfer:
A<15> = 0 READ; data transfer from device to an external controller; read measurement data
A<15> = 1 WRITE; data transfer from a controller to the device; write configuration data
4.2.1 Read
For reading a register, the 16-bit Read address (with A<15>=0) is sent to the MOSI pin. After 16 SCK
cycles, data of the specified address is read from the MISO pin. At the same time, the new address may
be clocked into the MOSI pin.
4.2.2 Write
For writing to a register, the 16-bit Write address (with A<15>=1) is sent to the MOSI pin. After 16 SCK
cycles, data following the address bits is written to the specified address. At the same time, the present
data of that register may be read from the MISO pin. Following the 16-bit of data (Data A in figure) a new
address may be written to the device. While the new address is written, the address from the previous
command is available at the MISO output.
(1)  = bitwise logical OR
Address
Address
MOSI
Data A
MISO
Address
Data B
0x8000  Address
(1)
Data A
MOSI
Previous Data
MISO
Previous Address
Data B
Previous Data
0x8000  Address
(1)