TM1637Six-digit LED driver with key scanning

TM1637 integrates a six-digit LED driver, six bytes of display RAM and a 16-key scanner in a 20-pin IC. It drives common-anode displays: GRID outputs source the digit current and SEG outputs sink the individual segment currents. A host updates the display through CLK and bidirectional DIO. The interface resembles I²C electrically, but it has no slave address and transfers each byte least-significant bit first. The host must release DIO for the acknowledgement clock. This reference covers the DIP-20 and SOP-20 packages in Titan Micro V2.4. Its example uses a 5 V host, six digits, two 10 kΩ pull-ups and local supply bypassing. Eight non-linear PWM settings adjust brightness; digit bytes directly select segments rather than decoding decimal numbers.