A Boost Converter with 3-6V Input and Fast Transient Digital Control Comprising a 90 ns-Latency Live-Tracking Window ADC

摘要

This paper presents a digitally controlled boost converter IC for high output voltage and fast transient applications. Thus, it is well applicable in automotive and industrial environments. The 3 V-to-6 V input voltage, 6.3 V output voltage, 1 A boost converter IC is fabricated in a 180 nm BCD technology. Digital control enables cost savings, advanced control concepts, and it is less parameter sensitive compared to common analog control. A 90 ns latency, 6-bit delay line ADC operates with a window concept, meeting high resolution requirements, e.g. in car battery applications. An output voltage live tracking is included for extending the ADC conversion window. A charge pump DAC provides high resolution, monotonicity, and short 128 ns conversion time. Further, a standard digital PI controller is enhanced by a simple but effective Δ V/Δt-intervention control. It results in 2.8x reduced output voltage deviations in case of load steps, scaling down the output capacitor value by the same factor.