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Lecture 3 – Common Elements. 9/26/2008. ECE 561 - Lecture . 1. Common Logic Elements. Review Lecture 2 sequential elements Examine the data sheet for some of these elements When using element in a design you start with the documentation for the element. 9/26/2008. ECE 561 - Lecture . 2.
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Lecture 3 – Common Elements 9/26/2008 ECE 561 - Lecture ECE 561 - Lecture 1
Common Logic Elements • Review Lecture 2 sequential elements • Examine the data sheet for some of these elements • When using element in a design you start with the documentation for the element 9/26/2008 ECE 561 - Lecture ECE 561 - Lecture 2
Common Sequential Elements • Basic Element • The Latch – A latch is a level sensitive component that stores and holds a value • What does level sensitive mean? • Flip Flops are edge triggered elements • F/F can be constructed of a Master Slave arrangement of 2 latches • Master is level sensitive to new input • On edge master is locked and its value is transmitted to the slave 9/26/2008 ECE 561 - Lecture ECE 561 - Lecture 3
Another Basic Elements • Register • Registers are composed of latches or F/Fs • Several uses • Register sets – driven from/drive busses • Input register for functional units • Output hold register for a functional unit • Configuration register 9/26/2008 ECE 561 - Lecture ECE 561 - Lecture 4
Edge Triggered F/F • Edge triggered flip-flops can be • Master Slave – formed from 2 latches • Discrete design ECE 561 - Lecture
Sequential ComponentsMultiple ICs • Cascaded Elements (Registers, Counters) • State Machines (FSM) • Controllers • Cooperating State Machines ECE 561 - Lecture
Data Books • Data Books List Components and their parameters ECE 561 - Lecture
More Data Book Components ECE 561 - Lecture
D F/F Data Sheet ECE 561 - Lecture
The inputs and outputs specs ECE 561 - Lecture
The circuit Implementation ECE 561 - Lecture
Various type of implmentation • Note this is • A Master-Slave • Implementation ECE 561 - Lecture
Timing • And has its own • Implementation • And timing ECE 561 - Lecture
Voltage and Current Specs ECE 561 - Lecture
Higher level components ECE 561 - Lecture
Use of data ECE 561 - Lecture
Use of data • You use the data to analyze circuit and then can answer questions on it as illustrated in the following ECE 561 - Lecture
Some Specifications ECE 561 - Lecture
Solution ECE 561 - Lecture
What are the states • Develop the state table • Pick a state to start with ECE 561 - Lecture
Self Starting Circuits • Circuits that end up in a valid state regardless of the state the FSM starts in. • Is this circuit self starting? • Go to www.wikipedia.com and look at material there on Finite State Machine ECE 561 - Lecture