VCR4N

N-channel Junction Field-Effect Transistor (JFET) designed specifically to operate as a Voltage-Controlled Resistor (VCR). Unlike standard JFETs optimized for amplification or switching, this device is engineered to provide a highly predictable and linear drain-source resistance (\(r_{DS}\)) that varies seamlessly according to the applied gate-source bias voltage - The primary characteristics of the component include:Drain-Source ON Resistance (\(r_{DS(on)}\)): 200 Ω minimum to 600 Ω maximum (measured at \(V_{GS} = 0\text{V}\), \(I_D = 0\text{A}\)).Gate-Source Cutoff Voltage (\(V_{GS(off)}\)): -3.5V to -7.0V.Gate-Source Breakdown Voltage (\(V_{(BR)GSS}\)): -15V minimum (some datasheets list absolute maximum limits up to -25V).Continuous Power Dissipation (\(P_{D}\)): 300 mW at \(T_A = 25^\circ\text{C}\).Packaging: Standard hermetically sealed through-hole metal can package (TO-72 / TO-206AF), with 3 pins configured as: Pin 1 (Source), Pin 2 (Drain), and Pin 3 (Gate & Case Connection).Primary ApplicationsThis device family is specifically intended for circuits where the drain-source voltage is a low-level AC signal with no DC component, preventing distortion in the resistive region. It is commonly implemented in:Small-Signal Attenuators: Creating dynamic, voltage-controlled voltage dividers.Automatic Gain Control (AGC): Controlling amplifier feedback loops and audio levelers.Tunable Filters: Altering the RC time constants of active filters dynamically via control voltage.Oscillator Amplitude Stabilization: Regulating output levels in Wien-bridge oscillators