Power Supply Topologies A Brief Overview The Most

安森美半导体 Power Supply Topologies 电源拓扑 ---A Brief Overview ---简述

The Most Popular Topologies 最常见的拓扑结构 Buck 降压 Boost 升压 Buck-Boost 降压-升压 Flyback 反激 Forward 正激 Two-Transistor Forward 双晶体管正激 Push-Pull 推挽 Half Bridge 半桥 Full Bridge 全桥 SEPIC C’uk

The Basic Pulse-Width Modulated Waveform 基本的脉冲宽度调制波形 These topologies all relate to switched-mode circuits. 这些拓扑结构都与开关式电路有关. Definition of the basic pulse-width modulated waveform is as follows: 基本的脉冲宽度调制波形定义如下: 占空比=负荷比=D

Buck, Boost and Buck-Boost 降压、升压和降压-升压 Buck 降压 Bucks the input down to a lower voltage. 把输入降至一个较低的电压。 负载 (R) Boost 升压 Boosts the input to a higher voltage. 把输入升至一个较高的电压。 负载 (R) Buck-Boost 降压-升压 A combination of buck and boost. Output is inverted, and its magnitude can be less or greater than the input. 降压和升压的组合。 输出反向，且其幅度可以大于或小于输 入。 负载 (R)

Flyback and Forward 反激和正激 Flyback 反激 Operates like the buck-boost, but the inductor has two windings and performs both as a transformer and inductor. 负载(R) 如降压-升压电路一样 作，但 是电感有两个绕组，而且同时 作为变压器和电感。 Forward 正激 Transformer-coupled version of the buck. 降压电路的变压器耦合形式。 The reset winding resets the core during the second portion of each cycle. 去磁绕组在每个周期的第二阶段 对磁芯去磁。 负载(R)

Two-Transistor Forward 双晶体管正激 负载(R) The two switches are turned on and off simultaneously. 两个开关同时打开和关闭。 When they turn off, the energy stored in the transformer reverses the polarity of the primary, causing the diodes to conduct and the transformer to reset. 开关关闭时，存储在变压器中的能量使初级的极性反转，从而使二极管导通并 使变压器复位。

Push-Pull 推挽 负载 (R) The switches (FETs) are driven out of phase and pulse-width modulated (PWM) to regulate the output voltage. 开关（FET）的驱动不同相，进行脉冲宽度调制 （PWM）以调节输出电压。

Half-Bridge 半桥 负载 (R) Very popular topology for higher-power converters. 较高功率变换器极为常用的拓扑结构。 The switches (FETs) are driven out of phase and pulse-width modulated (PWM) to regulate the output voltage. 开关（FET）的驱动不同相，进行脉冲宽度调制（PWM）以调节输出电压。

Full-Bridge 全桥 负载 (R) Very popular topology for higher-power converters. 较高功率变换器极为常用的拓扑结构。 The switches (FETs) are driven out of phase and pulse-width modulated (PWM) to regulate the output voltage. 开关（FET）的驱动不同相，进行脉冲宽度调制（PWM）以调节输出电压。

SEPIC and C’uk SEPIC 和 C’uk SEPIC (Single-Ended Primary Inductor Converter) (单端初级电感变换器) Output voltage can be either less than or greater than the input. 输出电压可以大于或小于输入电 压。 负载 (R) C’uk (Patented by Slobodan C’uk) (Slobodan C’uk的专利) Output is inverted. 输出反向。 – Magnitude of output voltage can be less or greater than the input. – 输出电压的幅度可以大于或小 于输入。 Input current and output current are both smooth. 输入电流和输出电流都是平滑的。 负载 (R)