CMOS CCO

Using two CMOS NAND gates (or inverters) and two transistors it is possible to construct a simple current-controlled oscillator (CCO). The circuit of figure 1 is based on a normal two-inverter astable multivibrator. When the output of Nl is high the output of N2 will be low and Cl will charge through T1 until the threshold voltage of Nl is exceeded, when the output ·of Nl will go low and the output of N2 high. T