Applications

Inverted Input Signal Polarity.

Inverted Input Signal PolarityInput signals are inverted before processing, reversing their logical polarity. Logic high (VDD) on the pin is read as logical '0', logic low (GND) as logical '1'. Useful for interfacing with active-low signals and simplifying software logic.

反相輸入信號極性，適用於主動低電平信號介面

• Pin voltage is inverted before logical processing
• High voltage (VDD) → Logical '0'
• Low voltage (GND/VSS) → Logical '1'
• Simplifies active-low signal handling
• Eliminates need for software inversion
• Suitable for: Active-low buttons, open-drain outputs, inverted logic systems

註

Useful for active-low signal sources

Simplifies software when dealing with inverted logic

Common with open-drain/open-collector outputs

:

• Active-low button: Pressed = 1, Released = 0 (no software inversion needed)
• Open-drain interrupt signals: Active = 1, Idle = 0
• Inverted enable signals: Enabled = 1, Disabled = 0
• Reset buttons: Pressed = 1, Released = 0

註

Particularly useful for:

• Interrupt inputs from active-low sources
• Open-drain bus signals (I2C-style)
• Reset and enable pins with active-low polarity
• Simplifying conditional logic in software