The SN74LS19AN is a hex inverter from the 74LS Schottky TTL family, with Schmitt-trigger inputs on all six gates. It takes a single input per inverter and outputs the logical complement, with built-in hysteresis that cleans up slow or noisy edges — useful for switch debouncing, oscillator circuits, or squaring up a waveform from a sensor. The 14-DIP through-hole package suits breadboard prototyping, legacy PCB retrofits, and designs that avoid surface-mount assembly. Supply range is 4.75 V to 5.25 V, commercial temperature grade 0°C to 70°C, so it is sized for benchtop, office, or indoor equipment — not the engine bay or a factory floor with wide thermal swings.
Maximum propagation delay is 30 ns at 5 V supply and 15 pF load. Output drive is 400 µA source and 8 mA sink.