Courtesy: Structured Computer Organization (5th Edition)
by Andrew S. Tanenbaum
Digital circuits can be constructed from a small number of primitive elements by combining them in innumerable ways.
1. GATES
A digital circuit is one which only two logical values are present. Typically, a signal between 0 and 1 volt represents one value (e.g. binary 0) and a signal between 2 to 5 volt represents other value (e.g. binary 1). Voltage outside these two ranges are not permitted . Tiny electronic devices, called gates , can compute various functions of these two-valued signals. The transistor has three connections to outside the world: the collector, the base, the emitter. When the input voltage, Vin, is below a certain critical value, the transistor turns off and acts like an infinite resistance. When Vin exceeds the critical value, the transistor switches on and acts like wire, causing Vout to be pulled down to ground.
by Andrew S. Tanenbaum
Digital circuits can be constructed from a small number of primitive elements by combining them in innumerable ways.
1. GATES
A digital circuit is one which only two logical values are present. Typically, a signal between 0 and 1 volt represents one value (e.g. binary 0) and a signal between 2 to 5 volt represents other value (e.g. binary 1). Voltage outside these two ranges are not permitted . Tiny electronic devices, called gates , can compute various functions of these two-valued signals. The transistor has three connections to outside the world: the collector, the base, the emitter. When the input voltage, Vin, is below a certain critical value, the transistor turns off and acts like an infinite resistance. When Vin exceeds the critical value, the transistor switches on and acts like wire, causing Vout to be pulled down to ground.
