Lateral p-i-n photodiodes have been fabricated, electrically tested, and incorporated into microwave control circuits such as an optically excited microwave atttenuator and reflection type phase shifter. Circuit design procedures for the loaded-line phase shifter with the optically controlled p-i-n photodiode are presented. The equal loss loading mode presented for the first time for the phase shifter circuits with lossy load allows an equal insertion loss of the phase shifter in both of its phase states. It is found that the insertion loss of the equal loss loading mode phase shifter constructed with the fabricated p-i-n photodiode load are about 3dB for 11.25$^{circ}$ bit and 1dB for 5.625$^{circ}$ bit for the frequency range of 2GHz to 11GHz.