mlx16305 Melexis Company, mlx16305 Datasheet
mlx16305
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mlx16305 Summary of contents
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... Industrial Security doors and machine guarding o General 2 wire analog sensors : Industrial pressure, strain gauge, … sensors (ref. MLX90308, MLX90314) Ordering Information Part No. Temperature Suffix MLX16305 E (-40°C to 90°C) 3901016305 Rev. 006 MLX16305 Interlock switch sensor interface IC Package Code DC (SOIC16 150mil) Page Data Sheet Apr/08 ...
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... The supplied current or the resulting supply voltage are measured and presented as an analog voltage to the microcontroller for interpretation. Each MLX16305 allows scanning switches for changes in switch state, and for any type of short/open circuit failure mode. MLX16305 devices in parallel on the same microcontroller ADC input. ...
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... TABLE OF CONTENTS FEATURES AND BENEFITS ....................................................................................................................... 1 APPLICATIONS............................................................................................................................................ 1 ORDERING INFORMATION......................................................................................................................... 1 1. OVERVIEW APPLICATION SCHEMATIC......................................................................................... 1-2 2. DESCRIPTION.................................................................................................................................... 2-2 3. ABSOLUTE MAXIMUM RATINGS ....................................................................................................... 4 4. MLX16305 ELECTRICAL SPECIFICATIONS ...................................................................................... 4 5. PIN ASSIGNMENT ................................................................................................................................ 5 6. BLOCK DIAGRAM ................................................................................................................................ 6 7. GENERAL DESCRIPTION .................................................................................................................... 7 8. PIN DESCRIPTION................................................................................................................................ 7 8. (VSUP).................................................................................................................................7 UPPLY ANGE 8. NPUT OLTAGE EFERENCE 8. (SENSE)..................................................................................................................8 ...
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... Output Current, SENSE Storage Temperature Range ESD Sensitivity (AEC Q100 002) Exceeding the absolute maximum ratings may cause permanent damage. Exposure to absolute- maximum-rated conditions for extended periods may affect device reliability. 4. MLX16305 Electrical Specifications DC Operating Parameters Tj = -40 Symbol Parameter Vsup Supply ...
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... RREF=1kOhm, VREF=5V DESCRIPTION 5V / 40mA 5V / 40mA 5V / 40mA Range 25V TTL Levels TTL Levels TTL Levels TTL Levels External Voltage Reference TTL Levels Ground (analog + digital 40mA 5V / 40mA 5V / 40mA Page MLX16305 Min Nom Max Unit -100 100 mV -150 150 mV 150 nF 0 150 250 us ...
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... VI_CTRL MEAS_OUT Encoder MUX_SENSE[0:2] ENABLE 3901016305 Rev. 006 Interlock switch sensor interface IC VDD MUX_SUP[0: SENSE SENSE V MEAS(VM) V MEAS(CM) Z OVERTEMP MUX_SUP[0:2] MUX_SUP[0:2] GND Page MLX16305 SENSE1 MUX_SUP[0:2] SENSE2 SENSE3 SENSE4 MUX_SENSE[0:2] SENSE5 SENSE6 *0.5 I /10 SENSE I OFFSET *0.9 RREF Data Sheet Apr/08 ...
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... SENSE pin. This way the state of a mechanical switch can be read or the switches can be diagnosed to detect open wires, shorts between SENSE pins, to Ground or to Supply. With the VI_CTRL input the MLX16305 can be set in either Current Mode (CM Voltage mode (VM) • ...
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... The VMEASOUT output voltage is not higher than Vref + 0.5V to avoid damaging of the microcontroller ADC input. • The MEASOUT pin is able to deliver minimum IMEAS. • MEAS_OUT can be made high impedant to allow multiplexing more MLX16305 devices in parallel when more than 6 channels are required. 3901016305 Rev. 006 Interlock switch sensor interface IC ...
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... VI_CTRL selects Current Mode or Voltage Mode (see below) 3901016305 Rev. 006 Interlock switch sensor interface IC and HIGH : V ≥ Page MLX16305 This disconnects all Data Sheet Apr/08 ...
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... When ENABLE = 0, the Overtemp condition can be read out on the MEAS_OUT pin by o setting MUX_SENSE = 111b. When ENABLE turns = 1 MuxSenseLatched remains = 111b. Changes on o MUX_SENSE[0:2] are neglected (= don’t care). 3901016305 Rev. 006 Interlock switch sensor interface IC OVERTEMP Z MuxSenseLatched[0:2] MuxSenseLatch[0:2] has to be set to 111b. Page MLX16305 MUX_SUP[0:2] MUX_SUP[0:2] Data Sheet Apr/08 ...
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... Rev. 006 Interlock switch sensor interface 000 100 000 001 000 001 000 000 001 Z , all other devices should have set ENABLE high. Page MLX16305 010 111 010 111 000 010 000 111 Data Sheet Apr/08 ...
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... ISENSE6*Rref/10 MEAS_OUT = Current on SENSE6 Pin (*)in CM VMEASOUT in the above table is the calculated value after subtracting the contribution of the offset = VMEASOUT - VMEASOUT (offset) Page MLX16305 Interlock switch sensor interface IC DESCRIPTION FAULT DETECTED on MEAS_OUT Normal <VMEAS_DIS; Else VMEAS>VMEAS_DIS, then the weak pull down is overruled ...
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... This is not allowed during normal operation. In case of short to voltages lower than 2V this pull-down current will decrease (resistive behavior). 3901016305 Rev. 006 Interlock switch sensor interface Meas_Verr1 SENSE * (1 + Meas_Verr1 SENSE + 0.5V REF < V MEAS_DIS Page MLX16305 MEASOUT_VOFFSET MEASOUT_VOFFSET Any voltage that is Data Sheet Apr/08 ...
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... Current mode (CM) The high accuracy of the MLX16305 can be used • to define clear boundaries of voltages. These boundaries will allow straightforward classification of the state of current modulated switches. • to measure industry standard current modulated sensors (for instance with the MLX90308, MLX90314) 10.1. Current to Voltage conversion principle The current ISENSE, supplied by the voltage regulator, is copied on the RREF pin with a 10:1 ratio ...
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... Any change to Rref implies a new offset measurement. • In case multiple MLX16305 devices are used in parallel, the offset should be measured and stored for every device. • An OPEN WIRE condition has Isense = 0mA, and as a result only Ioffset will contribute to the voltage over Rref ...
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... In the full system calculation additional errors have to be added for the tolerances on the sensor current, the ADC supply noise, etc. 3901016305 Rev. 006 Interlock switch sensor interface IC Vmeasout Worst case max Actual value Worst case min +5% +25uA -25uA No Operation 5mA ~ Isense +/-5% MEASOUT_ISENSE Page MLX16305 -5% Isense Data Sheet Apr/08 ...
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... SENSE / %Meas_Ierr1) + Ioffsetmax ] * R SENSE / 10 - IMeas_Ierr2 + Ioffsetmin ] * R SENSE / 10 + IMeas_Ierr2 + Ioffsetmax ] * R SENSE Vsup 25V 16.25V 11V 10.5V 9.5V 8V the 3V 4.5V Overcurrent limitation Overtemperature Detection Page MLX16305 * 0.9 REF * 0.9 REF * 0.9 REF * 0.9 REF Isense <30mA <40mA <45mA NOP No OPeration allowed Vref 7V 8.25V (next paragraph) Data Sheet Apr/08 ...
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... Overcurrent Limitation The MLX16305 has a built-in overcurrent limitation as protection against destruction and overheating. It also allows detecting short circuits to Ground on any of the SENSE channels. The voltage regulator will enter current limitation when the voltage over the external Rref resistance (VRREF) is between VREF and VREF + 3V: VREF < ...
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... In Current Mode: • In Voltage Mode: 13. Overtemperature Detection The MLX16305 has an internal overtemperature detection to protect against destruction and overheating. By applying the correct sequence on the digital input pins the OVERTEMP state is readable via the MEAS_OUT pin coded as: • VMEAS ≤ VMEAS_OTL = normal operation • ...
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... SENSE pin is Worst case Dissipation due the short: 50mA * 18V = 0.9W The controller will immediately diagnose the failure, and switch off the supply. Therefore no dissipation will be due to this. Worst case the MLX16305 will go in overtemperature and shut down itself. 3901016305 Rev ...
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... Long wires to the remote switches are prone to shorts to Ground, to supply or between the wires. The MLX16305 allows continuous failure mode diagnostics on each SENSE pin individually. The circuit works also if one of the SENSE pins is shorted to GND or Vbat (up to +25V); this means that such a short does not influence the measurement on other SENSE pins ...
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... Set one by one all other channels to evaluate shorts between the supplied pin and the other channels 3) Return to 1) For further discussions in this document it assumed that the flow for 1 pin could be completed in 0.5ms including the 250us settling time. 3901016305 Rev. 006 MLX16305 Interlock switch sensor interface IC Page Data Sheet Apr/08 ...
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... By applying the correct sequence on the digital input pins the MEAS_OUT pin can be set high impedant. This is of interest when using 2 or more MLX16305 in parallel for applications with more than 6 switches to be monitored. The MLX16305 devices are then multiplexed on the same ADC input channel. ...
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... Application Notes 16.1. System definition example with 2-wire Hall Switches The MLX16305 can be used with so called 2-wire Hall effect switches, like the MLX90275. These require typically a minimum operating voltage of 3.5V, and have 2 well defined current states. For instance: • Ioff: [5; 6.9]mA • Ion: [12; 17]mA An example is elaborated for • ...
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... Resistive switches are essentially also acting like current modulated switches. Therefore diagnostics are done in the same manner. The MLX16305 can supply plenty of cleaning current to allow the use of low cost switches. Nevertheless, aging may cause drift of the contact resistance values over life. The high accuracy of the MLX16305 allows tracking of such a case and early triggering of eminent failures ...
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... Ground Shift The MLX16305 allows connecting a remote ‘2-wire’ hall sensor with only 1 wire. Since the current is directly sensed, the measurement itself is immune to ground shift. Furthermore [Vref – Vgroundsift] should be guaranteed to be larger than the minimum supply current for the hall sensor. For instance for Vsupmin = 3.5V, and Vref = 5V, a groundshift of 1.5V is acceptable. ...
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... Of the use of certain Hazardous Substances) please visit the quality page on our website: http://www.melexis.com/quality.asp 18. ESD Precautions Electronic semiconductor products are sensitive to Electro Static Discharge (ESD). Always observe Electro Static Discharge control procedures whenever handling semiconductor products. 3901016305 Rev. 006 MLX16305 Interlock switch sensor interface IC Page Data Sheet Apr/08 ...
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... Package Information Unit : mm Package Type D min 9.80 SOIC16 Narrow Body max 10.00 3901016305 Rev. 006 Interlock switch sensor interface 3.80 5.80 1.35 0.10 1.27 4.00 6.20 1.75 0.25 Page MLX16305 b L α Package Code 0.33 0.40 0º DC16 0.51 1.27 8º Data Sheet Apr/08 ...
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... Or for additional information contact Melexis Direct: Europe and Japan: Phone: +32 1367 0495 E-mail: sales_europe@melexis.com 3901016305 Rev. 006 Interlock switch sensor interface IC www.melexis.com All other locations: Phone: +1 603 223 2362 E-mail: sales_usa@melexis.com ISO/TS 16949 and ISO14001 Certified Page MLX16305 Data Sheet Apr/08 ...