High Efficiency Open Collector Adaptive Bias SiGe HBT Differential Power Amplifier

A 28 dBm P<inf>out</inf> 5-GHz CMOS power amplifier using integrated passive device power combining transformer

“…This cascode topology provides a good deal of isolation between input and output, which improves circuit stability. The design uses two transistors with respective width/length of 1536 m/0.18 m and 3072 m/0.35 m. Two shunted resistors (R 1 ) and capacitors (C 1 ) at the gate-ends improve the stability of the PA, the transistor (M 3 ) in the bias circuit is a diode linearizer that extends the power gain and improves the linearity and PAE [10]. As the input power increases, the V gs of the transistor (M 3 ) compensates the V gs of transistor (M 1 ) that is dropped by the partial coupling of RF power through the coupling component.…”

High performance SiGe HBT power unit-cell for S-Band open collector adaptive bias power amplifier design

“…The open collector adaptive linearization technique has been investigated and published in our previous study [9]. The open collector linearizer is comprised of the base-emitter junction diodes HBT 4 (D 1 ) and HBT 5 (D 2 ) with an open collector transistor (HBT 3 ), a drain-gate connected Fig.…”

“…A simple RC feedback topology was applied to obtain the on-chip input match and necessary power gain. The open collector adaptive linearizer was implemented in the second stage to achieve both high linearity and PAE [9]. Thrity-four power unit-cells were combined in binary with total emitter area of 425.34 lm 2 for the second stage amplifier (HBT 2 ).…”

“…Consequently, the linearization range is relatively small. To overcome the problem, an open collector adaptive linearization technique has been investigated in our previous study [9]. In this work, a well designed SiGe HBT power unit-cell was investigated in both electrical and thermal properties.…”

0.35‐μm SiGe BiCMOS variable‐gain power amplifier for WiMAX transmitters

“…A voltage-controlled variable resistor [4] was used in the variablegain stage for automatic gain control. An open-collector adaptive bias control circuit was realized in power stage to achieve both high linearity and efficiency [5]. This variable-gain power amplifier was then fabricated in standard 0.35-m SiGe BiCMOS technology.…”