Consider the bistable circuit of Fig. 15.22(a) with the op amp’s negative-input terminal disconnected from ground and connected to a reference voltage VR. (a) Derive expressions for the threshold voltages V.and VTH in terms of the op amp’s saturation levels L and L ,R, R2, and VR: (b) Let L_ =-L_=V and R, = 10 k12. Find R, and V, that result in threshold voltages of O and V/10. RU R2 W + +/