74hc14 Oscillator Calculator [ RECENT – 2026 ]

r = 47e3 # 47k c = 10e-9 # 10nF print(f"hc14_osc_freq(r, c):.1f Hz") # ~967 Hz

For engineers requiring precise duty cycle control, you need an advanced calculator that uses the actual hysteresis window.

Given $V_T+$ (e.g., 3.15V at 5V supply) and $V_T-$ (e.g., 1.85V at 5V supply), the exact frequency is: 74hc14 oscillator calculator

$$ f = \frac1RC \cdot \ln\left( \fracV_CC - V_T-V_CC - V_T+ \right) $$

Advanced online calculators allow you to: r = 47e3 # 47k c = 10e-9

For a 5V 74HC14, the duty cycle is ≈ 45% (HIGH time shorter than LOW time).

Fine tuning: Use a fixed C and a trimmer potentiometer for R. For engineers requiring precise duty cycle control, you

For typical 5 V operation approximate thresholds:

If you prefer not to rely on a website, here is a simple Python script that acts as a command-line 74HC14 oscillator calculator. You can embed this in a spreadsheet or run it locally.

import math
def hc14_oscillator(r_ohms, c_farads, v_cc=5.0, method="heuristic"):
"""
Calculate frequency and period for a 74HC14 RC oscillator.
method: "heuristic" (0.55 constant) or "exact" (with thresholds)
"""
if method == "heuristic":
freq = 1 / (0.55 * r_ohms * c_farads)
else:  # exact for 5V typical thresholds
v_tplus = 3.15  # Typical at 25C, 5V
v_tminus = 1.85
num = v_tplus * (v_cc - v_tminus)
den = v_tminus * (v_cc - v_tplus)
freq = 1 / (r_ohms * c_farads * math.log(num / den))
period = 1 / freq
return freq, period