LM903 Datasheet | National Semiconductor

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 probe detection are incorporated within the device The circuit has possible applications in the detection of hydraulic fluid oil level etc and may be used with partially conducting fluids Features Y Y Y Y Y Y Y Y Y Y Flashing or continuous warning indication Warning threshold externally adjustable Control circuitry for thermal-resistive probe Switch on reset and delay to avoid transients 600 m A flashing lamp drive capability Short and open circuit probe detection 70V transient protection on supply and control input 7V - 18V supply range Internally regulated supply b 40 C to a 80 C operation Connection Diagram Dual-In-Line Package TL H 5699 - 1 Order Number LM903N See NS Package Number N16E C1995 National Semiconductor Corporation TL H 5699 RRD-B30M115 Printed in U S A Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage VCC Control Input Voltage (Pin 7) Transient Voltage (Pins 6 7 9) 10 ms (Note 1) Output Current (Pin 4) I4 (Sink) 18V 18V 70V 10 m A Operating Temperature Range Storage Temperature Maximum Junction Temperature Lead Temperature (Soldering 10 sec ) b 40 C to a 85 C b 55 C to a 150 C a 150 C 260 C Electrical Characteristics VCC e 12V CT e 33 m F RT e 7 5 k X TA within operating range except where stated otherwise Symbol Parameter Conditions Tested Limits (Note 2) Min VCC IS VREG Supply Voltage Supply Current Regulated Voltage Regulation Temperature Drift V6 - V3 VREF RREF V7 V7 I7 I7 R7 I12 Probe Current Reference Voltage Measurement Reference Voltage Reference Input Resistor Start Input Logic High Level Start...