Hwiseob Lee

  • Citations Per Year
Learn More
A CMOS power amplifier integrated circuit with an optimized dual-mode supply modulator is presented. The dualmode supply modulator, based on a hybrid buck converter consisting of a wideband linear amplifier and a highly efficient switching amplifier, provides two operation modes: envelope tracking (ET) for high average output power and average power(More)
This paper presents a two-stage PA MMIC using 0.4-μm GaN-HEMT. Two-stage structure is adopted to take its high gain property and simple inter-stage matching network. The size and loss of the inter-stage matching network can be reduced by including bond wires as a part of the shunt inductors in the matching network. The two-stage PA MMIC was(More)
A dual-mode supply modulator is presented for a complementary metal-oxide semiconductor envelope tracking power amplifier (PA) integrated circuit. The proposed supply modulator, based on a hybrid buck converter, has dual Class-AB buffers and dual switches for the linear and switching amplifiers, respectively. For high average output power levels [or(More)
This paper presents a method of improving efficiency for the two-stage Doherty power amplifier (DPA) using the optimized current of the peaking amplifier. The DPA has a two-stage structure for both the carrier and peaking amplifiers. The first stage of the peaking amplifier has an adjusted bias condition for a near Class-B operation, while the first stage(More)
Abstract This paper presents a high-power inverted Doherty power amplifier for broader operational bandwidth. After analyzing two operation modes according to the load modulation of the Doherty power amplifier, the inverted Doherty structure was selected. In the design, the load impedances for optimum broadband characteristics at both the back-off and peak(More)
  • 1