MLX75030 Datasheet, PDF (38/72 Pages) Melexis Microelectronic Systems – Universal ActiveLight Sensor Interface

MLX75030 Universal ActiveLight Sensor Interface
Datasheet
Control1 Byte
1000 1110
A₃A₂A₁A₀
Data1 Byte
Status Flag Byte
D₇..₀
Control2 Byte
A₃A₂A₁A₀ 0000
Address of target register
Data2 Byte
1000 1110
Data contents of register read
Table 18 : Read Register command
Control3 Byte
0000 0000
Data3 Byte
D₇D₆D₅D₄ D₃D₂D₁D₀
Note that the WR and RR commands are commands that require 3 bytes instead of 2 bytes.
An overview of the user registers that can be accessed with WR/RR commands and more general information concerning the
user registers can be found in section 7.4
7.2.2.10. SD – Start Diagnostics
The SD command will start a measurement cycle in which internal signals will be measured and converted. With this
command it is possible to test some circuits in the chip and check if they are functioning as expected.
The SD command behaves in much the same way as the SM commands: instead of uploading a SM command, a SD
command can be uploaded. This starts the measurement cycle and conversion of some internal signals. The pin DR goes high
when the cycle is completed, indicating that a read-out can be started. With the RO command it is possible to read out the
data and check if all the data values are within certain ranges.
After upload of a SD command, no other commands will be accepted till DR is high. This is done to avoid too much
disturbances in the analog part. Once DR is high, the next command will be accepted. An exception however is the Chip
Reset command. This will always be accepted. The SD command is not available in Standby Mode.
Similar to the SM command, the SD command has some measurement selection bits M₆..M₀ in the Control2 Byte. Different
measurements can be selected with these bits:
• M₆: setting this bit high enables the ADC diagnostics
• M₅: setting this bit high enables the DAC-ADC diagnostics
• M₄: setting this bit high enables the Ambient Diode checks
• M₃..M₀: (reserved)
Table 19 gives an overview of some execution times t_dr for the basic types of measurements.
Measurement Type
ADC Diagnostics
DAC-ADC Diagnostics
Ambient Diode checks
ADC + DAC-ADC + Ambient Diode Diagnostics
Min. t_dr (µs)
224
91
370
680
Max. t_dr (µs)
249
102
410
752
Table 19: Basic Measurement Execution Times t_dr
REVISION 005 – DECEMBER 2013
3901075030
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