Class-E/sub m/ switching-mode tuned power amplifier-high efficiency with slow-switching transistor

Closed-Form Design Equations for Class-EM Power Amplifier with Isolation Circuit

“…However, the absence of zero current switching (ZCS) and zero current derivative switching (ZCDS) produces an overlap between a non-zero current and a non-zero voltage across the switch during ON-to-OFF transition, resulting in a power loss that limits the practical efficiency of the Class-E PA. To address this problem, the Class-EM PA was proposed in [2]. It consists of a main circuit operating at the fundamental frequency (f0) and an auxiliary circuit operating at the second harmonic frequency (2f0) as shown in Fig.…”

“…It consists of a main circuit operating at the fundamental frequency (f0) and an auxiliary circuit operating at the second harmonic frequency (2f0) as shown in Fig. 4 of [2].…”

“…In [2], the main circuit was analysed separately from the auxiliary circuit, resulting in explicit design equations for the main circuit alone but not the auxiliary circuit. In addition, some of the design equations provided in Table I of [2] are incorrect and ambiguous.…”

“…In [2], the main circuit was analysed separately from the auxiliary circuit, resulting in explicit design equations for the main circuit alone but not the auxiliary circuit. In addition, some of the design equations provided in Table I of [2] are incorrect and ambiguous. For example, the provided equation of the load reactance (XL) implies that it is capacitive, but not inductive as indicated in Table I and in the circuit schematic of Fig.4 in [2].…”

“…In addition, some of the design equations provided in Table I of [2] are incorrect and ambiguous. For example, the provided equation of the load reactance (XL) implies that it is capacitive, but not inductive as indicated in Table I and in the circuit schematic of Fig.4 in [2]. Further, the provided equation for the injection resistance (Rinj) implies the presence of a physical resistor between the main and the auxiliary circuit, but on the other hand, the model of the Class-EM PA does not account for such physical resistor.…”