An OnTime Generator with Zero Quiescent Power Consumption Suitable for AOT Buck Converters A zeroquiescentpowerconsumption ontime generator is proposed in this paper, which is suitable for adaptive ontime (AOT) controlled Buck converters aiming at constant switching frequency. Instead of adopting operational amplifiers for voltagetocurrent conversion in conventional methods, an adaptive compensation mechanism is presented to realize a current linearly proportional to regulated output voltage, Vo, with no operational amplifier, which is used to obtain a voltage proportional to output voltage. Besides, a resistorcapacitor filter is utilized to achieve a ramp signal with slope proportional to supply voltage, V IN . By this method, an on time, T ON , proportional to VoVIN is realized, which is the core control law of AOT Buck converters. The proposed circuit is validated in a 0.18xcexbcm BCD technology, which demonstrates the accuracy of the TON is higher than 86% with temperatures and process variations. In the case of VIN5V and Vo1.2V, the average dynamic current of the proposed ontime generator is only 1.465xcexbcA in one switching period Tsw, while consuming zero quiescent power.

Variable offTime Peak Current Mode Control (VoTPCMC) as method for average current regulation in Buck Converter Drivers In automotive industry, every electronic device is driven by power switches. Indeed, the energy source is the car battery and it cannot, for instance, limit the output maximum voltage level. Consequently it could be higher than that supported by the load. The DCDC Buck converter acts by limiting the output variables, according with the load specifications thereby ensuring its correct operation. The overall circuit will be composed of a power stage, the basic DCDC converter, and a control loop, to provide a target output current value. This paper presents a control algorithm derived from an improved Peak Current Mode Control. The proposed algorithm defined Variable offTime Peak Current Mode Control (VoTPCMC) allows to contemporarily control in a DCDC converter the ripple and the average current values, leading to a reliable load driver. The algorithm operation is simulated and then tested on hardware using dSpace, a Rapid Control Prototyping setup.