It packs four independent NAND gates into a 14-SOIC package, each gate with two inputs.
The 90 ns propagation delay — slow but deliberate
The CD4011BM's max propagation delay is 90 ns at 15V with a 50 pF load. That's glacial compared to a 74LVC gate that switches in under 5 ns. But the trade-off is deliberate: the 4000B family trades speed for noise immunity and supply flexibility. If your signal chain runs at a few hundred kHz or slower — think pushbutton debounce, oscillator gating, or level translation — the 90 ns delay is invisible. The real win is the input logic levels: low is 1.5V to 4V, high is 3.5V to 11V, giving you a wide noise margin that a 3.3V-only logic family can't match.