mlx90308 Melexis Company, mlx90308 Datasheet
mlx90308
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mlx90308 Summary of contents
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... L (-40C to +150C) Description The MLX90308 is a dedicated microcontroller which performs signal conditioning for sensors wired in bridge or differential configurations. Sensors that can be used include thermistors, strain gauges, load cells, pressure sensors, accelerometers, etc. The signal conditioning includes gain adjustment, offset control, high order temperature and linearity compensation ...
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... Rev 006 Programmable Sensor Interface Page 2 MLX90308 Apr/04 ...
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... Table 1. MLX90308 Electrical Specifications DC operating parameters -40 to 140 A Parameter Symbol Instrumentation Amplifier * CSGN = 100 to 111: voltage mode only, not applicable to current mode. Output > 6.5V; MSB = 1 Output < 6.5V; MSB = 0 MLX902xx Name of Sensor Rev Y.X 22/Aug/98 3901090308 Rev 006 Programmable Sensor Interface 35V (unless otherwise specified). ...
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... Table 1. MLX90308 Electrical Specifications (continued) DC operating parameters -40 to 140 A Parameter Voltage Mode Output Stage ( See Voltage Mode) 3901090308 Rev 006 Programmable Sensor Interface 35V (unless otherwise specified). DD1 DC Test Conditions Min -1.3 Page 4 MLX90308 Typ Max Units +1.3 Apr/04 ...
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... Table 1. MLX90308 Electrical Specifications (continued) DC operating parameters -40 to 140 A Parameter MLX902xx Name of Sensor Rev Y.X 22/Aug/98 3901090308 Rev 006 Programmable Sensor Interface 35V (unless otherwise specified). DD1 DC Test Conditions Min Page 5 Page 5 MLX90308 Typ Max Units 7.1 Apr/04 ...
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... Table 1. MLX90308 Electrical Specifications (continued) DC operating parameters -40 to 140 A Parameter 3901090308 Rev 006 Programmable Sensor Interface 35V (unless otherwise specified). DD1 DC Test Conditions Min Page 6 MLX90308 Typ Max Units Apr/04 ...
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... Unique Features Customization Melexis can customize the MLX90308 in both hardware and firmware for unique requirements. The hardware design provides 64 bytes of RAM, 3 kbytes of ROM, and 48 bytes of EEPROM for use by the firmware. Special Information The output of the sensor bridge is amplified via offset and gain amplifiers and then converted to the correct output signal form in one of the output stages ...
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... Serial communications pin. Bi-directional serial communication signal for reading and writing to the EEPROM. 1 IO1 COMS IO2 2 GND 3 TSTB CMN 4 FLT CMO 5 OFC VMO VBN 6 VDD1 7 VBP FET TMP 8 VDD Figure 2. Pinout (SO16W (LW) Package) 3901090308 Rev 006 Programmable Sensor Interface Page 8 MLX90308 Apr/04 ...
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... Oscillator The MLX90308 contains a programmable on-chip RC oscillator. No external components are needed to set the frequency (87.8 kHz +/-1%). The MCU-clock is generated by a PLL (phase locked loop tuned for 614 kHz or 2.46 Mhz) which locks on the basic oscillator. The frequency of the internal clock is stabilized over ...
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... Measured_temp = Value from temperature N_factor = Filter value set by the user (four LSB’s of byte 25 of EEPROM), range 0-6. The filtered temperature value, Temp_f, is stored in RAM bytes 58 and 59. The data bit value, left justified bit field. Page 10 MLX90308 the signal . Apr/04 ...
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... CSGN[2:0] * Mode The MLX90308 firmware provides the capability of digitally processing the sensor signal in addition to the analog processing. This capability allows for signal correction. Signal Correction While in digital mode the firmware can perform signal correction. This is an adjustment to the output level ...
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... Temperature Gaps Fixed (1) 2 Gaps 3 Gaps 4 Gaps Table 6. Temperature & Signal Limitations Maximum number of temperature gaps 8 6 Figure 4. Signal Linearity Correction Output PC1 0 P2 Page 12 MLX90308 4 LSB of PNB_TNB hex) Maximum number of signal gaps MLX90308 PC5 PC4 PC3 PC2 Apr/04 ...
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... High Trigger Page 13 Page 13 MLX90308 FLT VDD1 FET VDD GND Power Supply Regulation IAO GNO VMO Gain VM TPO CMO CM CMN ADC Microcontroller & Core, Memory, DAC EEPROM TSTB Reset,Test,& Oscillator UART COMS MLX90308 Level 1 Level 2 Level 3 Apr/04 ...
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... Rev 006 Programmable Sensor Interface Communications The MLX90308 firmware transfers a complete byte of data into and from the memory based on a simple command structure. The commands allow data to be read and written to and from the EEPROM and read from the RAM. RAM data that can be read includes the current digitized temperature and digitized GNO ...
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... BCh to the UART, indicating that the reset has been received. EEPROM Data All user-settable variables are stored in the EEPROM within the MLX90308. The EEPROM is always re- programmable. Changes to data in the EEPROM do not take effect until the device is reset via a soft reset or power cycle. 12 bit variables are stored on 1.5 bytes. The 4 MSB’ ...
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... The eight LSB's of the second offset TC OFTC2[7:0]. The eight LSB's of Pressure Coefficient 4 PC4[7:0]. The eight LSB's of the second temperature point T2[7:0]. The eight LSB's of Pressure Point 4 (or Signature) P4[7:0]. The eight LSB's of the third gain TC GNTC3[7:0]. The eight LSB's of Pressure Coefficient 3 (or Signature) PC3 [8:0]. Page 16 MLX90308 Apr/04 ...
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... Two MSB's Pressure Point 3 Coefficient 3 PC3[11:8]). Two MSB's third Four MSB's fourth gain TC temperature point t3[9:8] or Four MSB's Pressure Two MSB's Pressure Coefficient 2 PC2[11:8]. Four MSB's fourth offset TC ordinate OFTC4[11:8] or Four MSB's Pressure Coefficient 1 PC1[11:8]. Page 17 Page 17 MLX90308 P3[9:8]. GNTC4[11:8] or Point 2 P2[9:8]. Two MSB's Pressure Poff[9:8]. Apr/04 ...
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... Value sent to output if checksum test fails bit value. These bytes are not used by the firmware and are available to the user. EEPROM checksum; value needed to make all bytes add to 0FFh. Must be set by user if checksum test is active. Page 18 MLX90308 Apr/04 ...
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... First temperature point. Pressure Coefficient 5 (8LSB). Second gain TC. Pressure point 5 (8LSB). Second offset TC. Pressure coefficient 4 (8LSB). Second temperature point. Pressure Point 4 (or Signature) (8LSB). Third gain TC. Pressure Coefficient 3 (or Signature) (8LSB). Third offset TC. Pressure Point 2 (or Signature) (8LSB). Page 19 Page 19 MLX90308 Apr/04 ...
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... Offset Ordinate of the current gap. Gain Ordinate of the current gap. 4 bits for the max. temperature address of the current gap; 4 bits for the min. temperature address of the current gap. Page 20 MLX90308 Two MSB's of fixed offset OF[9:8]. Four MSB's of the first offset TC OFTC1[11:8] Four MSB's, second gain ...
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... Address saved at interrupt. A-Accumulators saved at interrupt. B-Accumulators saved at interrupt. DAC gain (GN). DAC offset (OF). Filtered temperature. This bit number that is left justified bit field. Digitized linearity corrected signal value. Digital mode only. Address saved when call. Page 21 Page 21 MLX90308 Apr/04 ...
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... Also included in the circuit board is level shifting and glue logic necessary for RS-232 communications. The board has a socket with a single MLX90308 installed, and direct access to the pins of the IC. The user can easily attach bridge sensor to the board for in-system evaluation ...
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... GND VDD1 VMO FLT 10K GND FET VDD1 CMO 75 Ohms FLT 39 nF GND CMN 24 Ohms Page 23 Page 23 MLX90308 Supply 100 nF Output Ground Supply Output Ground Supply 100 nF 100 nF Depends on stability of the current loop Ground Apr/04 ...
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... Figure 10. Application Example Figure 10a. Programmable Oil Pressure Gauge of the supply voltage. The MLX90308 can be operated in Ratiometric Voltage Mode, in which the output (VMO) is tied to an A/D converter sharing the same supply and ground reference. A third wiring option is Current Mode, which allows the user milliampere current range to use as a 2-wire analog sensor ...
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... The sensitivity of the unconditioned output will also drift over temperature, as illustrated by the three slopes. The MLX90308 corrects these errors and amplifies the output to a more usable voltage range as shown in Figure 11b. MLX902xx Name of Sensor Rev Y.X 22/Aug/98 ...
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... Figure 12. MLX90308 Physical Characteristics, DF Package 0.51 0.33 10.50 10.10 3901090308 Rev 006 Programmable Sensor Interface 1. Notes: 1. All dimensions in millimeters. 2. Body dimensions do not include mold flash or protrusion, which are not to exceed 0.15mm. 2.65 2.35 0.010 min. Page 26 MLX90308 0.32 0.23 1.27 0.40 Apr/04 ...
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... Roadmap to qualify their package families for lead free processes also. Various lead free generic qualifications are running, current results on request. For more information on manufacturability/solderability see quality page at our website: http://www.melexis.com/html/pdf/MLXleadfree-statement.pdf MLX902xx Name of Sensor Rev Y.X 22/Aug/98 3901090308 Rev 006 Programmable Sensor Interface Page 27 Page 27 MLX90308 Apr/04 ...
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... For the latest version of this document our website at: Or for additional information contact Melexis Direct: E-mail: sales_europe@melexis.com E-mail: sales_usa@melexis.com 3901090308 Rev 006 Programmable Sensor Interface www.melexis.com Europe and Japan: All other locations: Phone: + Phone: +1 603 223 2362 Page 28 MLX90308 ISO/TS16949 and ISO14001 Certified Apr/04 ...