MLX75031 Datasheet, PDF (30/67 Pages) Melexis Microelectronic Systems – Optical Gesture & Proximity Sensing IC

MLX75031
Optical Gesture & Proximity Sensing IC
with Integrated LED Drivers
Datasheet
8.11.3. Detailed Explanation of SPI Instruction Words
8.11.3.1. NOP – Idle Command
The Idle Command can be used to read back the internal status flags that appear in the Data1 Byte.
The state of the device is not changed after the NOP command is uploaded.
8.11.3.2. CR – Chip Reset Command
After upload of a Chip Reset command, the sensor returns to a state as it is after power-up (Normal Running
Mode) except for the watchdog counter, the state of the MR line and the contents of the 'Rst' register. The
watchdog counter, the 'Rst' register and the state of the MR line will not be influenced by a CR command.
The CR command can be uploaded at any time, even during a measurement or a read-out cycle, provided
that the internal synchronization counter is reset. This is done by setting the CS pin high for at least a time
t_{cs_inter}.
When a CR command is uploaded during sleep mode resp. standby mode, the device goes automatically
into normal running mode. Note that this requires a time t_{wakeup_slp} resp. t_{wakeup_stby} before the internal analog
circuitry is fully set up again.
Right after upload of a CR command, the DR pin will go low during a time t_startup. Once the wake-up/reset
phase is complete, the DR pin will go high.
8.11.3.3. RSLP/CSLP – Request Sleep/Confirm Sleep
To avoid that the slave device goes unintentionally into sleep mode, the master has to upload two
commands. First a RSLP (Request Sleep) shall be uploaded, then the slave sets bit 4 of the internal status
flag byte high. The master has to confirm the sleep request by uploading a CSLP (Confirm Sleep). Afterwards
the slave will go into Sleep Mode, hereby reducing the current consumption, and the pin SLEEPB will switch
to low indicating that the device state changed into Sleep mode.
The pin SLEEPB will change state a time t_sleepb after the pin CS is set high at the end of the CSLP command.
The status flag can be cleared by uploading a CR command or a NRM command.
Note that uploading a Chip Reset makes the device switching into normal running mode.
The state of the DR pin will not be changed when going into Sleep Mode. However, after a wake-up event
the DR pin is set low during a time t_{wakeup_slp}.
REVISION 001 – JANUARY, 2013
39010xxxxx
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