LM903 NSC [National Semiconductor], LM903 Datasheet
LM903
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LM903 Summary of contents
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... LM903 Fluid Level Detector General Description The LM903 uses the thermal-resistive probe technique to measure the level of nonflammable fluids A low fluid level is indicated by a warning lamp operating in continuous or flashing mode All supervisory requirements to control the thermal-resistive probe including short and open circuit ...
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Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage V CC Control Input Voltage (Pin 7) Transient Voltage (Pins (Note ...
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Electrical Characteristics (Continued) V 12V Symbol Parameter Conditions V Auxiliary Output Lamp OFF 14 Voltage Lamp ON V Alarm Level (Difference Between First 1 and Second ...
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Circuit Timing Diagram Circuit Operation A measurement is initiated when the supply is applied pro- vided the control input pin 7 is low Once a measurement is commenced pin 7 is latched low and the ramp capacitor on pin 12 ...
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Equivalent Schematic Diagram 5 ...
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... Gas flow detection The cooling effect of gas flowing over a probe could be used to provide a warning signal from the LM903 in the event of gas failure Automatic top up With the LM903 strobed continuously the output may be stored buffered and used to drive sole- noid valves to correct a fluid level as required ...
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... National does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications Molded Dual-in-Line Package (N) Order Number LM903N NS Package N16E 2 A critical component is any component of a life ...