A 30 MHz voltage-mode controlled buck converter with fast transient responses is presented. An improved differential difference amplifier (DDA)-based Type-III compensator is proposed to reduce the settling times of the converter during load transients, and to achieve near-optimal transient responses with simple PWM control only. Moreover, a hybrid scheme using a digital linear regulator with automatic transient detection and seamless loop transition is proposed to further improve the transient responses. By monitoring the output voltage of the compensator instead of the output voltage of the converter, the proposed hybrid scheme can reduce undershoot and overshoot effectively with good noise immunity and without interrupting the PWM loop. The converter was fabricated in a 0.13 µm standard CMOS process using 3.3 V devices. With an input voltage of 3.3 V, the measured peak efficiencies at the output voltages of 2.4, 1.8, and 1.2 V are 90.7%, 88%, and 83.6%, respectively. With a load step of 1.25 A and rise and fall times of 2 ns, the measured 1% settling times were 220 and 230 ns, with undershoot and overshoot with PWM control of 72 and 76 mV, respectively. They were further reduced to 36 and 38 mV by using the proposed hybrid scheme, and 1% settling times were also reduced to 125 ns.

中文翻译：

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高频 DC-DC 转换器的快速瞬态技术

介绍了具有快速瞬态响应的 30 MHz 电压模式控制降压转换器。提出了一种改进的基于差分差分放大器 (DDA) 的 Type-III 补偿器，以减少转换器在负载瞬变期间的建立时间，并仅通过简单的 PWM 控制实现接近最佳的瞬态响应。此外，提出了一种使用具有自动瞬态检测和无缝环路转换的数字线性稳压器的混合方案，以进一步改善瞬态响应。通过监测补偿器的输出电压而不是转换器的输出电压，所提出的混合方案可以有效地减少下冲和过冲，并且具有良好的抗噪性并且不会中断 PWM 环路。该转换器采用 0.13 µm 标准 CMOS 工艺制造，使用 3.3 V 器件。输入电压为 3.3 V 时，在 2.4、1.8 和 1.2 V 的输出电压下测得的峰值效率分别为 90.7%、88% 和 83.6%。负载阶跃为 1.25 A，上升和下降时间为 2 ns，测得的 1% 建立时间为 220 和 230 ns，下冲和过冲分别为 72 mV 和 76 mV PWM 控制。通过使用建议的混合方案，它们进一步降低到 36 和 38 mV，并且 1% 的建立时间也减少到 125 ns。