ELM701
Pin Descriptions
VDD (pin 1)
OUT1 and OUT2 (pins 6 and 7)
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.
These are the actual output piezo drive pins.
Polarity is not important for either the piezo
element or for the ELM701, but there must be a
series resistor installed in one of the
connections. This resistor both limits the volume
of the sound produced, and also limits the piezo
current on energization. (the piezo element
appears as a relatively large capacitive load, so
requires a means to limit the charging current).
See the Electrical Characteristics for resistor
sizes.
in1, in2, in3, and in4
(pins 2, 3, 4, and 5 respectively)
These are CMOS input pins that are not used in
this design. Due to the nature of CMOS circuitry,
however, they can cause severe overheating,
and battery consumption is left floating. For this
reason all four of these pins must be connected
to either VSS or VDD.
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............................... ELM701P
200 mil SOIC..................................... ELM701SM
Absolute Maximum Ratings
Storage Temperature....................... -65°C to +150°C
Note:
Stresses beyond those listed here will likely damage
the device. These values are given as a design
guideline only. The ability to operate to these levels
is neither inferred nor recommended.
Ambient Temperature with
Power Applied....................................-40°C to +85°C
Voltage on VDD with respect to VSS............0 to +7.5V
Voltage on any other pin with
respect to VSS........................... -0.6V to (VDD + 0.6V)
All rights reserved. Copyright ©1999 Elm Electronics.
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
products or information, and does not authorize or warrant the use of any Elm Electronics product in life support devices and/or
systems. Elm Electronics reserves the right to make changes to the device(s) described in this document in order to improve
reliability, function, or design.
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ELM701DSB
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