MLX90326

MLX90326 Analog 0-5V Sensor Interface IC Features and Benefits Analog 0-5V ratiometric output Single pin programming (through output) Fast response time Extended temperature range Cost effective “electronic trimming” Second order compensation of offset and gain Internal temperature sensor provided Application Examples Pressure transducers, strain gauges, accelerometers, position sensors, etc… Industrial sensors Automotive after market sensors All resistive bridge sensors Ordering Information Part No. MLX90326LFR Temperature Code L (-40° to 150°C) C Package Code FR (SSOP 209 mil) 1 Functional Diagram 2 General Description The MLX90326 covers the most typical resistive type of Wheatstone bridge applications for use in an industrial or automotive after market environment. It is a monolithic silicon analog integrated sensor interface that converts small changes in resistors, configured in a full Wheatstone bridge on a sensing element, to large output voltage variations. The signal conditioning includes gain adjustment, offset control and second order temperature compensation in order to accommodate variations of the different resistive sensing elements. Compensation values are stored in EEPROM and can be reprogrammed with an interface circuit and a provided software. The MLX90326 is programmed with a single wire serial interface through the output pin. 3901090326 Rev 002 Page 1 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC Table of Contents 1 Functional Diagram........................................................................................................... 1 2 General Description .......................................................................................................... 1 3 Absolute Maximum Ratings .............................................................................................. 3 4 Pin Definitions and Descriptions ....................................................................................... 4 5 General Electrical Specifications....................................................................................... 5 6 General Description .......................................................................................................... 7 7 Unique Features ............................................................................................................... 7 8 Application Information ..................................................................................................... 8 8.1 Ratio-metric mode with external temperature sensor.................................................. 8 8.2 Ratio-metric mode with no external temperature sensor............................................. 9 8.3 Non Ratio-metric mode with external temperature sensor. ......................................... 9 8.4 Non Ratio-metric mode with no external temperature sensor. .................................. 10 9 Standard information regarding manufacturability of Melexis products with different soldering processes ........................................................................................................... 11 10 ESD Precautions........................................................................................................... 11 11 Package Information ..................................................................................................... 12 12 Disclaimer ..................................................................................................................... 13 3901090326 Rev 002 Page 2 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 3 Absolute Maximum Ratings Parameter. Supply Voltage, VDD- VSS Operating Temperature Range, Tenvironment Storage Temperature Range Programming Temperature Range Package Thermal Resistance ESD Sensitivity Table 1: Absolute maximum ratings Exceeding the absolute maximum ratings may cause permanent damage. Exposure to absolute-maximumrated conditions for extended periods may affect device reliability. 2 Min 4.5 -40 -50 -40 Max 5.5 150 150 125 130 Units V ºC °C °C °C/W kV HBM. CDF - AEC - Q100-002 Comments Operating within specifications 3901090326 Rev 002 Page 3 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 4 Pin Definitions and Descriptions Package Pin Nr 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Short Name INM ANAGND INP SUB TMP DIGGND Test TESTOU T TESTIN1 TESTIN2 FLT OUT Test VDD Dir IN gnd IN gnd IN gnd NC OUT IN IN OUT BI NC power Type Analog Analog Temp Function / Description Bridge Sensor Negative Analog Ground Bridge Sensor Positive Substrate Ground External Temperature Sensor (Resistor to supply) Digital Ground On module to ground. Test Test Test Analog Analog Supply Test Output. On module to ground Test Input 1: CLKEXT, TEST (3 level) Test Input 2: DATAIN, SCAN (3 level) Filter pin Analog output and communication pin On module to ground Supply Table 2: Pin definitions and descriptions 3901090326 Rev 002 Page 4 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 5 General Electrical Specifications DC Operating Parameters TA = -40 C to 150 C, VDD = 5.0V (unless otherwise specified) Parameter. Supply Voltage Supply Current Output capacitive load Output resistive load Output current capability Output short circuit current Digital output current VDD line inductance VDD=5V±10% ±2 0 Symbol VDD IDD No output load, VDD=5V±10% 10Ω < RSERIES < 10 kΩ To reach 5%VDD to 95%VDD Comments Min 4.5 4 0 2.4 Typ Max 5.5 9 100 Units V mA nF kΩ o o ± 1.9 ±50 ±5 22 mA mA mA H Signal path general Specifications Parameter. Overall gain Coarse gain Gdido 1bit programmable Symbol Comments Min 12.7 Typ Max 442 Units V/V V/V 3.25 (Gdido = 0) 13 (Gdido = 1) V/V 2 (Gdts = 0) 5 (Gdts = 1) V/V 1.24 (Gcs = 0) 1.9375 (Gcs =1) 0.448 1.8 0.99 63 V/V mV/Vsupply Gdts 1bit programmable Gcs 1bit programmable Fine gain Typical sensor output span that can be accommodated to achieve 4V output span Fgain 10 bit programmable 3901090326 Rev 002 Page 5 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC Typical sensor offset that can be compensated Output Offset programmable Output Offset resolution Overall non linearity Wake-up time at power up Output noise 47nF FLT capacitance with maximum gain Set by an external capacitor Best fit value 10 97.2 mV/Vsupply 90 0.1 ±0.1 10 5 %VDD %VDD %VDD ms mVrms Response time 0.1 ms Table 3: Electrical specifications 3901090326 Rev 002 Page 6 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 6 General Description The MLX90326 can be used with almost any type of resistive bridge sensor without the need of any additional signal conditioning. The differential input signal is offset compensated and amplified to achieve the desired output voltage. With a coarse gain calibration the MLX90326 can easily accommodate sensor output spans in the 1.8mV/V to 63mV/V range to achieve 4 V output span. Sensor output offsets up to 97.2mV/V (depending on the sensor output span and on the desired output offset) can be compensated with the coarse offset calibration to achieve an output offset in the 0.5V to 4.5V range. 7 Unique Features Offset canceling The offset of amplifier DIDO is cancelled by using a chopping mechanism. Also the amplifier DTS and all sample-and-hold circuits make use of an offset canceling mechanism. This means that the contribution of the on-chip offsets and offset drifts is negligible compared to the external sensor offset and offset drift. Coarse and fine second order calibration of the sensitivity and offset. The MLX90326 can be calibrated to achieve 4V output span for a sensor output span in the 1.8mV/V to 63mV/V and can compensate 0.4mV/V to 97.2mV/V input offset depending on the sensor output span and on the desired MLX90326 output offset voltage. A wide range of sensor sensitivity and offset temperature drift can be compensated with the second order fine gain and offset calibration. EEPROM All the calibration data is stored three times on an EEPROM and a majority voting is done when accessing data. Parity check is used to diagnose data corruption. After all calibrations parameters were successfully written to EEPROM, the EEPROM can be locked by sending a ‘Lock EEPROM’ command (see paragraph 6). This is strongly recommended to avoid in application mode data corruption. For reliability reasons, actually each calibration bit is stored three times in the EEPROM and the circuit uses a hardware majority voting system when accessing data. 3901090326 Rev 002 Page 7 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 8 Application Information 8.1 Ratio-metric mode with external temperature sensor. The external temperature sensor is only needed for applications where the temperature surrounding the customer sensor is different from the temperature surrounding the MLX90326. In the ratio-metric application mode, to keep the accuracy, the same supply should be used for the customer sensor, the MLX90326 and an ADC that makes the digital conversion of the analog output signal. The C1 capacitor value (output) is typically 47nF. Range: 0 – 100nF. The capacitor C2 on the FLT pin is optional. Typical value = 10nF. Range: 0 – 100nF. It is used to decrease the noise and set the bandwidth of the system. The decoupling capacitors C3 between the supply and the ground and C4 between output and supply have a typical value of 47nF. The external resistor R1 is placed between the TMP pin and the supply. It is used as an external temperature sensor. The external temperature sensor could be of type Panasonic, ERAS15J103V (R1 = 10k +/- 5%, TCR = 1500ppm/degC +/- 200ppm/degC) for the -40ºC to 140ºC temperature range. Typical pull up resistor R2 value is 2.4kOhm. 3901090326 Rev 002 VDD Page 8 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 8.2 Ratio-metric mode with no external temperature sensor. VDD VDD INM INP C3 1 2 3 4 5 6 7 14 13 12 11 10 9 8 C4 R2 OUT FLT C2 C1 C1, C2, C3, C4 and R2 have the same values as for the ratio-metric application with use of external temperature sensor. The internal temperature sensor can be used when the temperature surrounding the customer sensor and the MLX90326 is the same. 8.3 Non Ratio-metric mode with external temperature sensor. VDD VDD Vbat LM7805 C3 INM INP VDD C4 R1 1 2 3 4 5 6 7 14 13 12 11 10 9 8 R2 OUT FLT C2 C1 W ith the use of an external voltage regulator to supply the sensor, the MLX90326 as well as an ADC used for converting the analog output signal, the MLX90326 can be used in a non ratio-metric mode. An example of standard voltage regulator is the LM7805. C1, C2, R1 and R2 are the same as in the ratio-metric application mode. C4 has a typical value of 330nF and C3 of 100nF in this application mode. 3901090326 Rev 002 Page 9 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 8.4 Non Ratio-metric mode with no external temperature sensor. VDD VDD Vbat LM7805 C3 INM INP 1 2 3 4 5 6 7 14 13 12 11 10 9 8 C4 OUT C1 R2 FLT C2 In this application mode the LM7805 generates the supply for the sensor, for the MLX90326 and for an ADC used to convert the analog output signal in a digital value. C1, C2, C3, C4 and R2 are the same as in the non ratio-metric application mode with external temperature sensor. 3901090326 Rev 002 Page 10 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 9 Standard information regarding manufacturability of Melexis products with different soldering processes Our products are classified and qualified regarding soldering technology, solderability and moisture sensitivity level according to following test methods: Reflow Soldering SMD’s (Surface Mount Devices) • • IPC/JEDEC J-STD-020 Moisture/Reflow Sensitivity Classification for Nonhermetic Solid State Surface Mount Devices (classification reflow profiles according to table 5-2) EIA/JEDEC JESD22-A113 Preconditioning of Nonhermetic Surface Mount Devices Prior to Reliability Testing (reflow profiles according to table 2) Wave Soldering SMD’s (Surface Mount Devices) and THD’s (Through Hole Devices) • • EN60749-20 Resistance of plastic- encapsulated SMD’s to combined effect of moisture and soldering heat EIA/JEDEC JESD22-B106 and EN60749-15 Resistance to soldering temperature for through-hole mounted devices Iron Soldering THD’s (Through Hole Devices) • EN60749-15 Resistance to soldering temperature for through-hole mounted devices Solderability SMD’s (Surface Mount Devices) and THD’s (Through Hole Devices) • EIA/JEDEC JESD22-B102 and EN60749-21 Solderability For all soldering technologies deviating from above mentioned standard conditions (regarding peak temperature, temperature gradient, temperature profile etc) additional classification and qualification tests have to be agreed upon with Melexis. The application of Wave Soldering for SMD’s is allowed only after consulting Melexis regarding assurance of adhesive strength between device and board. Melexis is contributing to global environmental conservation by promoting lead free solutions. For more information on qualifications of RoHS compliant products (RoHS = European directive on the Restriction Of the use of certain Hazardous Substances) please visit the quality page on our website: http://www.melexis.com/quality.asp 10 ESD Precautions Electronic semiconductor products are sensitive to Electro Static Discharge (ESD). Always observe Electro Static Discharge control procedures whenever handling semiconductor products. 3901090326 Rev 002 Page 11 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 11 Package Information 3901090326 Rev 002 Page 12 of 13 Data Sheet Jan/08 MLX90326 Analog 0-5V Sensor Interface IC 12 Disclaimer Devices sold by Melexis are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. Melexis makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. Melexis reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with Melexis for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical lifesupport or life-sustaining equipment are specifically not recommended without additional processing by Melexis for each application. The information furnished by Melexis is believed to be correct and accurate. However, Melexis shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interrupt of business or indirect, special incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of Melexis’ rendering of technical or other services. © 2005 Melexis NV. All rights reserved. For the latest version of this document, go to our website at www.melexis.com Or for additional information contact Melexis Direct: Europe, Africa, Asia: Phone: +32 1367 0495 E-mail: sales_europe@melexis.com America: Phone: +1 603 223 2362 E-mail: sales_usa@melexis.com ISO/TS 16949 and ISO14001 Certified 3901090326 Rev 002 Page 13 of 13 Data Sheet Jan/08