The design approach and performance of a 5-bit digital phase shifter implemented with 0.25 lm GaN HEMT technology for X-band phased arrays are described. The switched filter and high-pass/low-pass networks are proposed in this article. For all 32 states of the 5-bit phase shifter, the RMS phase error less than 5.5 degrees, RMS amplitude error less than 0.8 dB, insertion loss less than 12 dB and input/output return loss less than 8.5 dB are obtained overall 8-12 GHz. The continuous wave power capability is also measured, and a typical input RF P-1dB data of 32 dBm is achieved at 8 GHz. (c) 2017 Elsevier Ltd. All rights reserved.