What this single 3-state buffer does on a 5V bus
The TC7SET126FU,LJ(CT is a single non-inverting buffer with a 3-state output, part of Toshiba's TC7SET series. It operates from a 4.5V to 5.5V supply, making it a direct fit for 5V CMOS and TTL logic buses where you need to isolate or gate a single signal line. The output goes high-impedance when the output-enable pin is low, letting multiple buffers share a common bus without contention. Each output can sink or source 8mA, enough to drive a standard CMOS input or a low-power LED indicator.
The 4.5V to 5.5V supply window is tight — it is a 5V-only part, not a wide-range logic like 74LVC. If your rail dips below 4.5V, the buffer may not switch correctly; plan a clean 5V rail with ±10% tolerance.
Supplied in a 5-pin SOT-353 package (also marked as 5-TSSOP or SC-70-5), the footprint is 2.0 mm × 2.1 mm with 0.65 mm pin pitch. The ROHS3 compliance means no exemption-listed lead, cadmium, or mercury — clean for EU RoHS and most global environmental regulations.
Toshiba lists the TC7SET126FU,LJ(CT as Active with no announced end-of-life. That means no LTB (last-time-buy) window to chase, and no forced redesign for obsolescence in the near term.