一种高速宽带升压转换器斜坡补偿电路的设计  

Design of the Slope Compensation Circuit for a High-Speed Broadband Boost Converter

作　　者：王雪原 周建伟 林鹏程 

机构地区：[1]北工业大学电子信息工程学院,天津市电子器材与器件重点实验室,天津300401 [2]英特格灵芯片(天津)有限公司,天津300130

出　　处：《半导体技术》2017年第9期656-662,共7页Semiconductor Technology

摘　　要：峰值电流模式升压型直流-直流转换器在连续导通模式下,当占空比大于50%时会出现闭环不稳,产生次谐波振荡等现象,需进行斜坡补偿。讨论了斜坡补偿的意义,并设计了一种结构简单的电流检测和斜坡补偿电路,该电流检测采用一种电流负反馈电路进行电压箝位,斜坡补偿时未采用传统的加法器对补偿斜率相加的方式,而是直接将采样电流和补偿电流在电流节点加和,解决了比较器引入附加回路对带宽的限制,瞬态响应速度较快。此电路基于Magna Chip公司HL18GFL 0.18μm工艺设计,并进行了流片。测试结果表明,斜坡斜率为3.17 mV/ns,满足系统稳定性要求。本电路面积仅为128.7μm×62.8μm,电流检测精度在5%以内。In the continuous-conduction mode, closed-loop instability would happen in the peak current-mode boost DC-DC converter when the duty cycle is more than 50%,resulting in sub-harmonic oscillation and so on,and the slope compensation is required. The meaning of slope compensation was discussed,and a simple current detection circuit and slope compensation circuit were designed. A current negative feedback circuit was used in the current detection for voltage clamping. The traditional adder to add the slope signal was not used in the slope compensation,while the sampling current and the compensation current were added at the current node directly,solving the limitation of the bandwidth due to the introduction of additional loop by the comparator and the speed of the transient response was faster.This circuit was designed and fabricated based on HL18 GFL 0. 18 μm process of Magna Chip. The test results show that the ramp slope is 3. 17 m V/ns,which meets the system stability requirements. The circuit area is only 128. 7 μm×62. 8 μm,and the current detection accuracy is less than 5%.

关 键 词：峰值电流模式 升压转换器 斜坡补偿 电流检测 次谐波振荡 

分 类 号：TN402[电子电信—微电子学与固体电子学] TN432