Open-drain hex inverter for mixed-voltage bus and wired-OR logic
The SN74HC05DR packs six independent inverter gates with open-drain outputs into a 14-SOIC package. Open-drain means the output transistor pulls low to ground but floats high — the pull-up resistor is external, so the high-level voltage is set by whatever rail you connect it to, not the chip's own VCC. That makes this part useful for level-shifting a 5 V logic signal to a 3.3 V or 12 V bus, or for wired-OR connections where multiple outputs share a common pull-up. Each gate sinks 5.2 mA when low, enough to drive a standard TTL load or an LED through a series resistor. The supply range spans 2 V to 6 V, covering both 3.3 V and 5 V logic families without a separate level translator.
Timing and signal integrity at the board level
Propagation delay is 20 ns max at 6 V with a 50 pF load. That delay sets the maximum data rate through the gate — for a clock or strobe line running above about 25 MHz, the gate's own delay eats into the timing budget and a faster family like 74LVC or 74AHC is a better fit. At lower speeds, the 74HC family's noise margin and wide supply range are the advantage. Quiescent current is 2 µA max, so the chip adds negligible draw to the supply rail when the outputs are static. Input logic thresholds track the supply ratio: low is 0.5 V to 1.8 V, high is 1.5 V to 4.2 V at VCC = 5 V. That means a 3.3 V CMOS output driving a 5 V-powered SN74HC05DR input is marginal on the high-level threshold — a pull-up to 5 V on the input side cleans it up.
Temperature grade and package fit
Rated for -40°C to 85°C ambient, the industrial temperature range covers most indoor and outdoor equipment — control panels, telecom line cards, instrumentation, and automotive cabin electronics. The 14-SOIC body (3.90 mm width) is a standard footprint shared by thousands of logic parts, so the PCB layout is interchangeable with other 14-pin SOIC logic ICs from the same family. ROHS3 compliant per the manufacturer's declaration.
Sourcing and lifecycle posture
Sourced through authorized distribution channels; quoted to order against your BOM quantity. Availability and current pricing are confirmed at RFQ time. The 74HC series is a mature logic family with broad second-source availability from multiple manufacturers. If you need a pin-compatible alternative from a different brand, the 74HC05 in a 14-SOIC package from NXP, ON Semiconductor, or STMicroelectronics drops into the same footprint with the same electrical ratings.