App note: I2C controlled keypad scan IC

The TCS8418 is an I2C controlled keypad scan chip for up to 80 buttons:

• Operating Power-Supply Voltage Range of 1.65 V to 3.6 V
• Supports QWERTY Keypad Operation Plus GPIO Expansion
• 18 GPIOs Can Be Configured into Eight Inputs and Ten Outputs to Support an 8 × 10 Keypad Array (80 Buttons)
• 10 Byte FIFO to Store 10 Key Presses and Releases

TCS8418 in QFN and CSP (BGA) packages
TCA8418E in CSP (BGA) package

Thanks for the tip MichaelZ!