MLX90288 Datasheet, PDF (9/19 Pages) Melexis Microelectronic Systems – SMD Programmable Linear Hall Sensor IC Featuring Analog Ratiometric Output

MLX90288
SMD Programmable Linear Hall Sensor IC
Featuring Analog Ratiometric Output
6 EEPROM Mapping
6.1 EEPROM Description
All calibration parameters on the MLX90288 are stored in a 32 x 16bit non-volatile EEPROM.
The EEPROM parameters from the first 29 addresses are stored with triple redundancy, to correct if any
EEPROM bit would loose its content, by using majority voting. Consequently, an EEPROM word in this part
of EEPROM only holds the information of 5 calibration bits + 1 locking bit at index 15. The EEPROM word
stored at address 0 thus looks like this:
{LOCK0,PARAM[4:0],PARAM[4:0],PARAM[4:0]}
If bit index 15 is set, the EEPROM word is permanently locked, making it impossible to overwrite the given
address in PTC mode.
ID bits from the last 3 addresses are not stored with redundancy. The MLXID is not programmable in PTC
mode, hence guaranteeing traceability of the parts.
There are no constraints on the EEPROM readout in PTC mode.
6.2 Melexis Programmable Parameters
6.2.1 OSCTRIM [4:0]
• Will be calibrated at MLX production
• Trims oscillator frequency around 1 MHz
6.2.2 TRIMCTAT [4:0]
• Will be calibrated at MLX production
• Trims PTAT and CTAT to have both current sources at the same level at 25°C
• This calibration is necessary to allow correct TC1 trimming with a single measurement at either hot or
cold
• The calibration compensates mismatch in both PTAT and CTAT current sources
6.2.3 ITRIM[2:0]
• Will be calibrated at MLX production
• Trims the current reference used throughout the analog part to a predefined value
6.2.4 IPLATE[3:0]
• Will be calibrated at MLX production
• Defines the current through the Hall plates, impacting the total gain
6.2.5 TC1ST[6:0]
• Will be calibrated at MLX production
• Programming first order sensitivity temperature drift compensation
• Piecewise linear compensation between hot and cold temperatures = TC1ST
3901090288
Rev 002
Page 9 of 19
May/12