The standard TTL series has a typical propagation delay of 10ns (the term propagation delay was introduced in Chapter 4 and will be covered in more detail later hauler) By this we mean that when an in...

At the output of all gates there is a capacitive load (CL) caused by the input capacitance of the next stage. This could be a printed circuit board interconnect or quite simply an oscilloscope lead....

Diode transistor logicThe DTL or diode transistor logic first became available commercially in 1962. The circuit diagram for a two-input DTL NAND gate is shown in Fig. 9.2(a) and although it is no lon...

The bipolar junction transistor or BJT as it is more commonly known can be considered in digital terms as a simple single-pole switch. It physically consists of three layers of semiconductor (which ca...

So far we have seen how to design both combinational and sequential circuits. These will, on paper, successfully perform many different functions but may well fail if the practicality of the hardware ...

Now we shall design a D-type based circuit that will count up or down, under the control of a single external input, through the first five prime numbers (in binary). We must ensure that the circuit w...

The general form of a synchronous sequential circuit is shown in Fig. 8.1. To recap, this has: external inputs, A, and outputs, Z; a combinational block can be considered in two parts; and 'memory’ in...

Synchronous sequential circuits were introduced in Section 5.1 where firstly sequential circuits as a whole (being circuits with ‘memory’) and then the differences between asynchronous and synchronous...