A 45–2500-MHz Push–Pull Driver PA With Cross Coupled and Negative Feedback Technique

Derivative superposition technique (DST) is a common linearization technology for designing driver power amplifier (DPA). However, the performance of DST is sensitive to frequency variation. This letter presents a method to improve the 1-dB bandwidth of the DST. The negative feedback resistance (NFR) and cross-coupled capacitance (CCC) are combined with DST as the core of DPA which is applied to a 45–2500-MHz wireless transmitter. The DPA implements a good performance in the measured 193% relative bandwidth. The linearity is measured with 1-dB compressed output power from 9 to 10.2 dBm and the third-order intermodulation less than −37.23-dBc over the whole frequency band. The overall die area of the PA is 0.044 mm ² at TSMC 180-nm technology process, and it draws 22.8 mA from the 1.8-V supply voltage.