The SN74ALS00AD is a Texas Instruments 74ALS-series quad 2-input NAND gate in a 14-SOIC package. With a 2 V high-level input threshold and 0.8 V low-level threshold, the device accepts standard TTL levels directly — no level translation needed when driving from a 5 V TTL output. Output drive is asymmetric: 400 µA source, 8 mA sink. The 8 mA low-level drive handles a fan-out of 10 standard LS loads; the 400 µA high-level drive limits the pull-up fan-out to about 5 loads. For heavily loaded buses, buffer the output or use a higher-drive family like 74ALS with a larger output stage.
Active production and compliance documentation
The device is supplied in tube packaging. The 14-SOIC footprint (0.154" body width, 3.90 mm) is a standard JEDEC MS-012 variant — the same land pattern used by the 74AHCT and 74HCS series in SOIC-14, so a board laid out for those families accepts this part without a footprint change.
How the SN74ALS00AD compares to the SN74AHCT132DR
The AHCT132 includes Schmitt-trigger inputs with hysteresis (0.5 V to 0.6 V low threshold, 1.9 V to 2.1 V high threshold) versus the ALS00's fixed TTL thresholds (0.8 V low, 2 V high). Propagation delay is similar: 9 ns for the AHCT132 versus 11 ns for the ALS00 at 5 V, 50 pF. The AHCT132's Schmitt-trigger inputs reject slow edges and noise on the input lines — a meaningful advantage in noisy backplane or cable-drive applications where the ALS00's standard inputs may double-clock on a slow rise time.