A digital phase shifter is described where each bit of the phase shifter has a circuit block including one PIN diode in parallel with one transmission line. The phase shifter requires only one PIN diode and one transmission line per bit circuit block. Each PIN diode behaves like a simple switch for phase shifting. When the PIN diode is forward biased (“on” state), current flows through the PIN diode and the RF signal is not phase shifted. When the pin diode is not forward biased (“off” state), current flows through the transmission line parallel to the PIN diode and the RF signal is phase shifted by the transmission line. The digital phase shifter may have n circuit blocks in series, and adjacent PIN diodes may share a current when both are on. The phase shifter may be implemented in a phased array or reflect array antenna including multiple phase shifters.