8-stage divider and oscillator

74AHC1G4208 is a 8-stage divider and oscillator. It consists of a chain of 8 flip-flops. Each flip-flop divides the frequency of the previous flip-flop by two, consequently the 74AHC1G4208 counts up to 28 = 256. The single inverting stage (X1 to X2) functions as a crystal oscillator or an input buffer for an external oscillator. When used as a buffer the output X2 should be left floating. The frequency of the output (Q) is the frequency applied to X1 divided by 256. The divider advances on the negative-going transition of X1.

The X1 input is overvoltage tolerant. This feature allows the use of this device as a voltage level translator in mixed voltage environments.