Description

The ELM409 is digital filter circuit that is used to interface mechanical contacts to electronic circuits. All mechanical contacts, whether from switches, relays, etc. will have inherent ‘bounce’ when they make or break a connection. When that contact is used for the electrical input to a digital circuit, the bounces can easily be incorrectly interpreted as multiple inputs. The ELM409 contains all of the logic that is typically required to remove the bounce from such signals, and provide a signal that has only one transition.

Features

• Standard and extra long debounce times

• Schmitt input provides hysteresis

• Complementary circuit outputs

• Needs no external timing components

• Low power CMOS design - typically 1 mA at 5V

• Wide supply range - 3.0 to 5.5 volt operation

• High current drive outputs

Applications

• Pushbutton interface for logic circuits

• Limit switch monitoring

• Time delay generation

• Power on sequencing