A synchronous boost converter with high speed and high accuracy peak current control unit

Abstract

A 3 MHz, 48W Boost converter with high speed and high accuracy Peak Current Control Unit (PCCU) is presented. The Boost controller IC adopts a novel PCCU consisting of a fully differential open-loop operational transconductance amplifier (OTA) and a trans-impedance amplifier (TIA), which can minimize the delay and error of the whole control loop. In the PCCU, the compensated output of error amplifier is moved forward to improve the control accuracy further. This IC is designed in CSMC 0.8 um 60 V BCD process. The simulation results show the Boost converter operates at 3 MHz and the peak current control error is 1.3% under the worst situation. The delay of peak current trigger point to the low side gate driver (LDRV) output is 25.14 ns and the delay of the compensated output of error amplifier to LDRV output is 37.56 ns.