AIS3624DQ datasheet(21/41 Pages) STMICROELECTRONICS

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AIS3624DQ

Digital interfaces

SDO are respectively the serial port data input and output. Those lines are driven at the

falling edge of SPC and should be captured at the rising edge of SPC.

Both the read register and write register commands are completed in 16 clock pulses or in

multiple of 8 in the case of multiple read/write bytes. Bit duration is the time between two

falling edges of SPC. The first bit (bit 0) starts at the first falling edge of SPC after the falling

edge of CS while the last bit (bit 15, bit 23, ...) starts at the last falling edge of SPC just

before the rising edge of CS.

bit 0: RW bit. When 0, the data DI(7:0) is written into the device. When 1, the data DO(7:0)

from the device is read. In latter case, the chip will drive SDO at the start of bit 8.

bit 1: MS bit. When 0, the address will remain unchanged in multiple read/write commands.

When 1, the address is auto incremented in multiple read/write commands.

bit 2-7: address AD(5:0). This is the address field of the indexed register.

bit 8-15: data DI(7:0) (write mode). This is the data that is written into the device (MSb first).

bit 8-15: data DO(7:0) (read mode). This is the data that is read from the device (MSb first).

In multiple read/write commands further blocks of 8 clock periods will be added. When the

MS bit is ‘0’, the address used to read/write data remains the same for every block. When

the MS bit is ‘1’, the address used to read/write data is increased at every block.

The function and the behavior of SDI and SDO remain unchanged.

5.2.1

SPI read

Figure 7. SPI read protocol

The SPI Read command is performed with 16 clock pulses. Multiple byte read command is

performed adding blocks of 8 clock pulses at the previous one.

bit 0: READ bit. The value is 1.

bit 1: MS bit. When 0, does not increment the address; when 1, increments the address in

multiple reads.

bit 2-7: address AD(5:0). This is the address field of the indexed register.

bit 8-15: data DO(7:0) (read mode). This is the data that will be read from the device (MSb

first).

bit 16-... : data DO(...-8). Further data in multiple byte reads.

SPC

SDI

SDO

DO7 DO6 DO5 DO4 DO3 DO2 DO1 DO0

AD5 AD4 AD3 AD2 AD1 AD0

AIS3624DQ Datasheet(PDF) 21 Page - STMicroelectronics