关键词: 半桥倍流整流变换器, 厚膜混合集成电路, 低压大电流, AMB基板, 同步整流, 互联工艺

Abstract: To meet the demand for low-voltage high-current power supply in new equipment such as AI chips and DSPs, this paper addresses the issues of low efficiency and large volume in traditional two-stage power supply architectures by studying a single-stage half-bridge current-doubler rectifier converter based on thick-film hybrid integration technology. By analyzing the bottleneck problems of high conductor current density, poor heat dissipation capacity and high high-frequency loss in thick film processes in high-current applications, it is proposed to adopt high thermal conductivity Active Metal Brazed substrates and an optimized power interconnection structure to enhance the current-carrying capacity and heat dissipation performance. The circuit employs the LM5035C control chip to achieve feedforward voltage-mode modulation and synchronous rectification drive, while the transformer is designed with a 4:1 turn ratio parallel structure to reduce winding losses. A test prototype with an input voltage range of 20–38 V, an output voltage of 1 V, and an output current of 50 A was developed. The peak efficiency of this prototype exceeded 90%, verifying the feasibility of the structure proposed in this paper in achieving high power density, high efficiency, and good dynamic response, and providing a reliable integrated power solution for low-voltage high-current applications in military electronics.

Key words: half-bridge current-doubler rectifier converter, thick-film hybrid integrated circuit, low-voltage high-current, AMB substrate, synchronous rectification, interconnection process