ELM411 Datasheet, PDF (2/4 Pages) ELM Electronics – Debounce Circuit with Latch

ELM411
Pin Descriptions
VDD (pin 1)
This pin is the positive supply pin, and should
always be the most positive point in the circuit.
Internal circuitry connected to this pin is used to
provide power on reset of the microprocessor, so
an external reset signal is not required. Refer to
the Electrical Characteristics section for further
information.
Out1 (pin 2)
This is the output pin for the first debounce
circuit. A logic low applied to In1 (pin 7) will
cause this pin to go to a logic high level, once
the input is stable for the debounce period.
Similarily, a logic high (or open circuit) at pin 7
will result in this pin being driven to a logic low
level after the debounce period.
Out2 (pin 3)
This is the output pin for the second debounce
circuit. Refer to the description for pin 2.
In3 (pin 4)
This is the input for circuit 3. Levels are standard
CMOS, not schmitt trigger, so the use of external
delay capacitors, etc. is not recommended. An
internal pullup resistor is provided to allow direct
interface to mechanical contacts (refer to the
specs for further information).
Out3 (pin 5)
This is the output pin for the third debounce
circuit. At powerup, this pin is reset to a logic low
level. On each falling edge of In3 (pin 4), the
logic level at this pin will alternate between high
and low levels.
In2 (pin 6)
This is the input pin for the second debounce
circuit. Refer to the description for pin 4.
In1 (pin 7)
This is the input pin for the first debounce circuit.
Refer to the description for pin 4.
VSS (pin 8)
Circuit common is connected to this pin. This is
the most negative point in the circuit.
Ordering Information
These integrated circuits are available in either the 300 mil plastic DIP format, or in the 200 mil SOIC surface
mount type of package. To order, add the appropriate suffix to the part number:
300 mil Plastic DIP............................... ELM411P
200 mil SOIC..................................... ELM411SM
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Every effort is made to verify the accuracy of information provided in this document, but no representation or warranty can be
given and no liability assumed by Elm Electronics with respect to the accuracy and/or use of any products or information
described in this document. Elm Electronics will not be responsible for any patent infringements arising from the use of these
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reliability, function, or design.
ELM411DSB
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