I need to measure the time in the range of (1-100) nanoseconds between two events. Please suggest me any circuit or device to accomplish that. Waiting for all of your response.
PIC processors with CTMU Charge Time Measurement Unit (some PIC18, PIC24) are an option. They are implementing a classical time to analog principle, utilizing a dedicated hardware block and the built-in ADC. Consult the Microchip datasheet for details.