The AVX-S series includes three basic models (specifically the AVX-S1, AVX-S2 and AVX-S3). The basic functional equivalent circuits are shown on the following pages. Model AVX-S1 is specifically designed for ultra high-speed, low current applications (rise times as low as 200 ps, bandwidths to 100 MHz, and peak currents to 400 mA). The AVX-S1 is employed in the AVO-9 series of diode drivers. Model AVX-S2 is intended for applications with rise times greater than 2 ns and currents above 1 Ampere. Model AVX-S3 is specifically designed for use with the AVO-2 and AVO-5 series pulse generators (which provide currents in the range of 5 to 50 Amperes). The input series blocking capacitor in Models AVX-S1 and AVX-S2 presents a low impedance to pulse signals, while the shunt inductor presents a high impedance to pulse signals but a low impedance to the DC bias. The resistor in series with the laser diode is selected to ensure that the impedance at the IN port is 50 Ohms. Normally a laser diode resistance (i.e., dV/dI at the operating point) of approximately 1 Ohm is assumed.
