ENGG1100|Term2|201415 题香港中文大學 The Chinese University of Hong Kong Analog and digital signals Analog signals: the signal can be any values within the valid range Voltage Example: Range =0>10 Volts 10M E.g. The signal can be 1 356 Volts or2.432∨o|ts Analog value Digital signals: It can only be HGH( or called‘1’) or loW(or called 0). Examples In TTL Transistor-transistor -logic OV standard High=1≈5vots,LoW=0≈0vot Time(ms Usually several bits(more than one Voltage digital bit)are used to represent a One digital Bit number corresponding to an 5V analog value E.g. 8-bit to represent a value from 0 to 28-1=255, or 32-bit to OV represent a value from o to 23-1 Time(ms V15.02.09 IntroductionENGG1100 | Term 2 | 2014-15 Analog and digital signals • Analog signals: the signal can be any values within the valid range – Example: Range =0 → 10 Volts – E.g. The signal can be 1.356 Volts or 2.432 Volts • Digital signals: It can only be HIGH (or called ‘1’ )or LOW (or called ‘0’). Examples: – In TTL Transistor-transistor-logic standard: • High=‘1’  5 volts, Low=‘0’  0 Volt • Usually several bits (more than one digital bit) are used to represent a number corresponding to an analog value • E.g. 8-bit to represent a value from 0 to 28 -1 =255, or 32-bit to represent a value from 0 to 2 32 -1 V15.02.09 Introduction 6 Voltage Time (ms) Voltage Time (ms) 5 V 0 V 10 V 0 V 1 1 Analog value One Digital Bit