TM1637 clock
Connecting TM1637 to Arduino:
Arduino TM1637 display
PIN #7 ------------------ CLK
PIN #8 ------------------ DIO
3.3V ------------------ VCC
GND ------------------ GND
Blog post: https://blog.3d-logic.com/2015/01/21/arduino-and-the-tm1637-4-digit-seven-segment-display/