What this open-drain NAND gate does differently
The CD40107BPSR is a dual 2-input NAND gate with open-drain outputs, each sinking 68 mA.
68 mA sink — the spec that changes the BOM
Most 4000-series gates are rated for a few milliamps of output drive. The CD40107BPSR's 68 mA sink capability means you can replace a separate transistor or MOSFET driver with one package, saving board area and component count. The open-drain output also allows wired-OR connections: multiple gates can share a pull-up resistor, which is useful for interrupt lines or shared bus arbitration in low-speed control logic. Propagation delay is 100 ns at 15V with a 50 pF load, so this isn't a high-speed gate — keep it in the sub-5 MHz range for clean edges. The input logic levels are specified as 1.5V to 4V for low and 3.5V to 11V for high, which gives good noise margin across the supply range.
Active and available — no end-of-life concern
The CD40107BPSR is in an 8-SOIC package and is an active product.
