74LS14 Datasheet, PDF (3/6 Pages) National Semiconductor (TI) – Hex Inverters with Schmitt Trigger Inputs

Switching Characteristics at V_CC e 5V and T_A e 25 C (See Section 1 for Test Waveforms and Output Load)
Symbol
Parameter
R_L e 2 kX
C_L e 15 pF
C_L e 50 pF
Min
Max
Min
Max
Units
t_PLH
Propagation Delay Time
5
22
8
25
ns
Low to High Level Output
t_PHL
Propagation Delay Time
5
22
10
33
ns
High to Low Level Output
3