A Synchronous Buck Converter With a Wide Input Voltage Range Using Simulated Peak Current Mode Control

With the rapid development of automotive infotainment, industrial DC-DC motors and telecom servers, the demand for buck converters with high-input or wide-input voltage is increased. This paper proposes a synchronous buck converter with a wide input voltage range, utilizing a simulated peak current mode. The proposed simulated peak current control mode removes the need for a separate slope compensation circuit. By integrating a slope compensation current directly into the ramp generator, it eliminates subharmonic oscillation issues when the duty cycle in current mode control exceeds 50%, thereby simplifying circuit design. The proposed simulated peak current mode retains the key advantages of peak current mode, such as feedforward control, easy overcurrent protection, and easy loop compensation, while significantly enhancing the loop's immunity to interference. This enhancement reduces the noise sensitivity of the pulse width modulation circuit, eliminates false switch turn-offs caused by leading-edge spikes, and removes the need for external low-pass filters. Furthermore, with the integration of high-voltage regulation technology, it achieves a wide input–output range, broadening its application scope. As a result, the proposed mode is more robust and reliable in applications with high stability and anti-interference requirements, such as automotive infotainment, industrial DC–DC motors, and telecom servers, offering strong support for reliable and precise power system performance. The proposed converter is implemented using UMC 250 nm BCD technology and operated at a frequency range of 50 kHz–1 MHz, with the maximum output current up to 7 A, a wide input voltage range of 6–100 V, and an output voltage range of 1.215–80 V. Besides, excellent minimum ripple/output ratio (0.0325%) and maximum power efficiency (90.93%) are achieved.