The 74VHC125FT,74VHC126FT are high speed CMOS QUAD BUS BUFFERs fabricated with silicon gate C2MOS technology. They achieve the high speed operation similar to equivalent Bipolar Shottky TTL while maintaining the CMOS low power dissipation. The 74VHC125FT requires the 3-state control input G to be set high to place the output into the high impedance state, whereas the 74VHC126FT requires the control input G to be set low to place the output into high impedance. An input protection circuit ensures that 0 to 5.5 V can be applied to the input pins without regard to the supply voltage. This device can be used to interface 5 V to 3 V systems and two supply systems such as battery back up This circuit prevents device destruction due to mismatched supply and input voltages

Wide operating temperature: Topr = -40 to 125 
High speed: Propagation delay time = 3.8 ns (typ.) at VCC = 5.0 V
Low power dissipation: ICC = 2.0 μA (max) at Ta = 25 
High noise immunity: VNIH = VNIL = 28 % VCC (min)
Power-down protection is provided on all inputs.
Balanced propagation delays: tPLH ≈ tPHL
Wide operating voltage range: VCC(opr) = 2.0 to 5.5 V
Low noise: V = 0.8 V (max)