Explore LM339 pins, signal names, electrical functions and connection guidance for each package.
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Sinks current when IN+ is below IN−. Releases when IN+ is above IN−.
Add a 10 kΩ pull-up to +5 V and connect a high-impedance logic input.
An external pull-up is required for a defined HIGH.
Sinks current when IN+ is below IN−. Releases when IN+ is above IN−.
Leave open when unused.
An external pull-up is required for a defined HIGH.
Shared positive supply for all four comparators.
Use +5 V with 100 nF bypass to pin 12.
Classic LM339: 2–30 V operating range.
Negative input for the comparator whose output is pin 2.
Connect to the 2.0 V reference when unused.
Positive input for the comparator whose output is pin 2.
Connect to GND when unused.
Stay within the common-mode range.
Negative input for the comparator whose output is pin 1.
Connect to the 2.0 V reference.
Positive input for the comparator whose output is pin 1.
Connect to VIN, the adjustable signal.
Stay within the common-mode range.
Negative input for the comparator whose output is pin 14.
Connect to the 2.0 V reference when unused.
Positive input for the comparator whose output is pin 14.
Connect to GND when unused.
Stay within the common-mode range.
Negative input for the comparator whose output is pin 13.
Connect to the 2.0 V reference when unused.
Positive input for the comparator whose output is pin 13.
Connect to GND when unused.
Stay within the common-mode range.
Shared negative supply / ground.
Connect to signal and supply returns.
Sinks current when IN+ is below IN−. Releases when IN+ is above IN−.
Leave open when unused.
An external pull-up is required for a defined HIGH.
Sinks current when IN+ is below IN−. Releases when IN+ is above IN−.
Leave open when unused.
An external pull-up is required for a defined HIGH.
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