MLX90313

Programmable IR Sensor Interface

MLX90313 Programmable IR sensor Interface

Page 16

Rev 1.0 21-July-2001

3901090313

IRGAIN2 bit functions

Bit

POR

val

Function

X

100

Vref = 4V

X

101

Vref = 4.5V

RSEL[3:0]

X

0000-1111

Select the value of the analog ground for IR signal path.The bits are

5, RSEL4 is in LPF register (see ‘ADC’ part)

TEMPGAIN

Read access: No. The data is accessible for read via SPI only from eeprom address 02h.

Write access: Directly to internal register in test mode. To EEprom if WP-register is correctly set.

TEMPGAIN bit functions

Bit

POR

val

Function

TRSEL[1:0]

X

00-11

Reference voltage for Tambient measurement at ADC interface

input.

IRSEL[2:0]

X

000-111

Current mirror ratio: See under M in table ‘Temp chain gain settings’

in the section on the Temp-amplifier chain (analog features)

GCT[5:0]

X

000000-

111111

Temp-gain: See table ‘Temp-chain gain settings’ in the section on

the temp-amplifier chain (analog features)

CONFREG1

Read access: Directly from internal registers or EEprom.

Write access: Directly to internal register in test mode. To EEprom if WP-register is correctly set.

CONFREG1 bit functions

Bit

POR

val

Function

Fatal Error

X

1

Flags Multiple eeprom failure. Hamming coding can detect and correct only one bit

per address. Bit will be cleared when going in test mode,disabling EEPROM

protection and returning in normal mode.( for diagnostics only)

ENVR

X

1

Stops the internal reference for DAC (Pin VREF). The reference voltage can be

supplied externally. If ENDAC=0 then VREF is input.

HVSUP

1

1

Enable the regulator for battery supply. NOTE!!! After POR this regulator will be

always on. It can be stopped from EEPROM data.

0

External supply of ADC reference to AGND pin.

SELADREF

X

1

Enable the internal ADC reference (connected to AGND pin).

0

Sets threshold level for Rel1 to THRel1 in EEprom (address 75h)

POTMET

X

1

Sets potentiometer input (pin IROUT) as threshold level

0

Sets Tobject as target voltage for comparator Comp1

COMP1V

X

1

Sets Tambient as target voltage for comparator Comp1

0

Sets polarity of Comp1: Inverting

COMP1P

X

1

Sets polarity of Comp1: Non-inverting

0

Output of Temp amplifier path is connected to ADC

BYPTEMP

X

1

Connects TINP-TINN directly to the ADC, bypassing the Temp-chain

0

Sets Tobject as target voltage for Rel1

REL1V

X

1

Sets Tambient as target voltage for Rel1

0

Sets polarity of Rel1: Inverting

REL1P

X

1

Sets polarity of Rel1: Non-inverting

EEWREN

0

1

Enables write access in EEPROM *write protect

TESTMODE

0

1

Indicates chip is in test mode *write protect

*control bits EEWREN and TESTMODE are write protected. Their values can be set only with writing the

appropriate data in ‘Test’ and ‘WP’ registers. These bits are flags which indicate the system operation