Signal Range Converter using OPAMP

Comprehensive design with error analysis, E12/E24/E96 resistor selection, and practical recommendations

The calculator converts a defined input voltage range to a defined output voltage range through a single-OPAMP stage (differential amplifier, non-inverting or inverting topology). From the min/max input and output voltages it derives the gain and offset, selects resistor values from the chosen E-series, and calculates the resulting Vref. It also estimates output error from OPAMP offset voltage, resistor tolerance and temperature drift, and checks the achievable bandwidth against the OPAMP's GBW and slew rate.

How to use: Enter input and output voltage ranges. The calculator will design resistor values from selected series (E12/E24/E96), calculate Vref, perform error analysis (offset, tolerance, drift), and verify frequency limits (GBW, Slew Rate).
Signal Range Parameters
Circuit Configuration
Operational Amplifier Parameters
Determines input impedance

Linear transformation:
V_out = G × V_in + V_offset

where:
  G = (V_out_max - V_out_min) / (V_in_max - V_in_min)
  V_offset = V_out_min - G × V_in_min

Output voltage:
V_out = (R3/R1) × (V_in - V_ref)

For matched resistors: R1=R2 (inputs), R3=R4 (feedback/ground)
Gain: G = R3/R1

V_ref calculation:
V_ref = V_in_min - (V_out_min / G)

Offset voltage error:
ΔV_os = G × V_os

Resistor tolerance error (RSS):
ΔG/G ≈ √2 × tol (typical error)

Worst case:
G_worst = (R2 × (1+tol)) / (R1 × (1-tol))

Temperature drift error:
ΔV_drift = G × (dV_os/dT) × ΔT

Total error (RSS):
ΔV_total = √(ΔV_os² + ΔV_tol² + ΔV_drift² + ΔV_bias²)
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