General Description
The LM1815 is an adaptive sense amplifier and default gating circuit for motor control applications. The sense amplifier provides a one-shot pulse output whose leading edge coincides with the negative-going zero crossing of a ground referenced input signal such as from a variable reluctance magnetic pick-up coil.
In normal operation, this timing reference signal is processed (delayed) externally and returned to the LM1815. A logic input is then able to select either the timing reference or the processed signal for transmission to the output driver stage.
FEATUREs
● Adaptive hysteresis
● Single supply operation
● Ground referenced input
● True zero crossing timing reference
● Operates from 2V to 12V supply voltage
● Handles inputs from 100 mV to over 120V with external
resistor
● CMOS compatible logic
APPLICATIONs
● Position sensing with notched wheels
● Zero crossing switch
● Motor speed control
● Tachometer
● Engine testing