8.2.2.1.1 Low-Voltage Capacitor

The low-voltage capacitor (LV Cap) couples the time-varying components of the power amplifier output signal into the line coupling transformer. The LV Cap must have a large enough capacitance to appear as a low impedance throughout the signal band of interest; 10-μF is a common value for signals in the range of 35 kHz to 150 kHz. The voltage rating of the LV cap should be sufficient to withstand the clamping voltage of the TVS diode (that is, the transient voltage suppressor (see Circuit Protection more information) operating under surge conditions. Generally, this limit must be equal to the power amplifier supply voltage or slightly higher.