This paper presents a low-power, in 180 nm CMOS HV process integrated oscillator, that is capable of creating low frequencies for wirelessly controllable LED drivers in optoelectronic brain implants. The oscillator system consists of a thyristor-based delay element with a power consumption of 4.65nW and a delay time of 13.31 ms. The delay is precisely controlled by a 4.13nA resistor-less and temperature-compensated current reference. Simulations revealed a frequency of 12.56 Hz with a temperature coefficient of 262ppn/°C between -20°C and 120°C and an overall power consumption of 120nW.