In Gasoline Direct Injection (GDI) System, Various Injection types are needed to reduce polluting emission and fuel consumption. Therefore, high precision injection is required for small fuel amounts region. For the injection of small fuel amounts, the GDI solenoid injectors need to be worked in the half lift region. Although, injected fuel amount deviations in this region tend to increase by the injector needle lift deviations and the issue is to inject small fuel amounts with high precision. To reduce deviations, an attempt was made to analyze lift timing from driving waveform and adjust injected fuel amounts by ECU. In the injector opening time detection, it focused on a particular feature found on the current waveform at the time of injector needle open, and in the injector closing time detection, it focused on a particular feature found on the voltage waveform at the time of injector needle closure. The current and voltage waveform are analyzed by ECU and the algorithm which is able to detect each characteristic point is developed. High-precision as well as wide dynamic range is required to detect the characteristic point. Electronic parts to detect by ECU is micro-controller or ASIC. If micro-controller is used, there will be processing load issue by continuous high-speed sampling. On the other hand, ASIC is able to capture and process waveform with high precision as well as by high speed sampling. Therefore, the detection part is integrated into dedicated ASIC. As a result, the ECU has potential to detect Injector open-close needle lift timing with high precision without increasing micro-controller processing load significantly.