Programmable array logic (PAL) architecture has a programmable AND array at the input and a fixed OR array at the output.
The programmable AND array of a PAL device is similar to that of a programmable logic array (PLA) device. … Read More
Programmable Logic Array (PLA)
A programmable logic array (PLA) device has a programmable AND array at the input and a programmable OR array at the output, which makes it one of the most versatile programmable logic devices.
The figure below, shows the internal architecture … Read More
Basic Structure of a Programmable ROM (PROM)
The architecture of a programmable read only memory (PROM) allows the user to use the hardware in implementing an arbitrary combinational function of a given number of inputs. When utilized as a memory device, n inputs of the ROM (called … Read More
Choosing Between TTL & CMOS for Your Digital Logic Design
There are two families of logic devices called TTL and CMOS. For those who are new to these devices, TTL stands for transistor transistor logic devices and CMOS for complementary metal-oxide semiconductor devices. Bipolar junction transistors are the building blocks … Read More
Transistor Transistor Logic (TTL)
Transistor transistor logic (TTL) is a logic family implemented with bipolar process technology that combines or integrates NPN transistors, PN junction diodes and diffused resistors in a single monolithic structure to get the desired logic function. The NAND gate is … Read More
Programmable Logic Device (PLD)
Besides memory devices and microprocessors, logic devices make up one of the essential classes of devices utilized in digital computing systems. Memory devices like ROM & RAM are used for information storage such as software instructions of a program, … Read More
3 Categories of Digital Logic Families
Digital ICs are usually fabricated using either bipolar devices or MOS devices or a combination of the two. We can classify the logic families into the following categories based on whether they are manufactured using bipolar, MOS or a combination … Read More
Digital Signal Processor (DSP) as an Embedded System
A digital signal processor (DSP) is a single IC-microcomputer device and its functionality mirrors that of a microcontroller however DSPs are normally better suited for high-speed floating point calculations. In other words, a DSP is a processor core or chip … Read More
Common Instructions Types in PIC Microcontrollers
Every microcontroller family has its own set of instructions that are typically carried out in a similar set of operations though using different syntax. This is exhibited in the variation in the internal architecture of various types of microcontrollers. … Read More
Data Registers
Data registers are used in microcomputers to hold data temporarily. Normally this data can be accessed faster than if it were to be fetched from the memory.
The figure below shows a 4-bit data register that utilizes a negative edge-triggered … Read More