Features
1) Built-in bias resistors enable the configuration
    of an inverter circuit without connecting external
    input resistors (see equivalent circuit).
2) The bias resistors consist of thin film resistors
    with complete isolation to allow negative biasing
    of the input. They also have the advantage of
    almost completely eliminating parasitic effects.
3) Only the on / off conditions need to be set for
    operation, making device design easy.