Part of the Day · SN74HC14 — SOIC-14 hex Schmitt-trigger inverter (marking HC14)

Part of the Day · 2026-11-05

Six inverters (NOT gates) with Schmitt-trigger inputs in one chip. The input switches at different voltages on the way up and on the way down (hysteresis), so even slow or noisy signals come out as clean High/Low levels. Widely used for switch debouncing, RC oscillators and signal cleanup. The marking on the TI SOIC-14 (D) chip is HC14.

Actual size

↓ Actual size, left edge aligned to 0 on the ruler

One ruler tick = 1mm. On PC this is actual size on a 24-inch FHD monitor at 100% zoom; on iPhone it adjusts automatically. For other screens, use “Calibrate ruler” below.

Enlarged (SOIC-14 · top view · approx. 12×)

Pins 1 1A (input 1) · 2 1Y (output 1) · 3 2A (input 2) · 4 2Y (output 2) · 5 3A (input 3) · 6 3Y (output 3) · 7 GND · 8 4Y (output 4) · 9 4A (input 4) · 10 5Y (output 5) · 11 5A (input 5) · 12 6Y (output 6) · 13 6A (input 6) · 14 VCC (supply)

Package SOIC-14 · Marking HC14

Key specifications

Values are from the Texas Instruments datasheet.

Marking and pins

Marking code HC14 · Pins 1 1A (input 1) · 2 1Y (output 1) · 3 2A (input 2) · 4 2Y (output 2) · 5 3A (input 3) · 6 3Y (output 3) · 7 GND · 8 4Y (output 4) · 9 4A (input 4) · 10 5Y (output 5) · 11 5A (input 5) · 12 6Y (output 6) · 13 6A (input 6) · 14 VCC (supply)

Typical uses

• Debouncing buttons and switches (after an RC filter, for a clean signal)
• Turning slow or noisy signals into clean digital signals
• Simple RC oscillator (clock) with one resistor and one capacitor
• Inverting digital signals and clock inputs

Companion & similar parts

• SN74HC14DR — Same chip, SOIC-14 on reel (2,500 pcs) — the tube version SN74HC14D is obsolete
• SN74HC14PWR — Same chip in the smaller TSSOP-14 (body 5 × 4.4mm)
• SN74HC14N — Same chip in DIP-14 (through-hole, body 19.3 × 6.35mm)
• SN54HC14 — −55 ~ 125℃ version from the same datasheet (ceramic packages)

As the datasheet says, unused inputs must be tied to VCC or GND (never left floating). Unused outputs can be left open, but must not be connected directly to VCC or GND. The thresholds change with supply voltage (VT+ typ. 1.2V at 2V, 3.3V at 6V), so check the table for your supply voltage when designing. The tube version SN74HC14D is obsolete, so order the reel version SN74HC14DR today.