1 / 12

Other Technologies

Other Technologies. Off-the-shelf logic (SSI) IC Logic IC has a few gates, connected to IC's pins Known as Small Scale Integration (SSI) Popular logic IC series: 7400 Originally developed 1960s Back then, each IC cost $1000 Today, costs just tens of cents. V. C. C. I. 14. I. 13. I.

erasto
Download Presentation

Other Technologies

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Other Technologies • Off-the-shelf logic (SSI) IC • Logic IC has a few gates, connected to IC's pins • Known as Small Scale Integration (SSI) • Popular logic IC series: 7400 • Originally developed 1960s • Back then, each IC cost $1000 • Today, costs just tens of cents V C C I 14 I 13 I 12 I 11 I 10 I 9 I 8 I C I 1 I 2 I 3 I 4 I 5 I 6 I 7 GND

  2. 7400-Series Logic ICs

  3. n k p n w s b ( ) (b) Decompose into 2-input AND gates Using Logic ICs • Example: Seat belt warning light using off-the-shelf 7400 ICs • Option 1: Use one 74LS08 IC having 2-input AND gates, and one 74LS04 IC having inverters (a) Desired circuit 14 13 12 11 10 9 8 I I I I I I I k (c) Connect ICs to create desired circuit p w 74LS08 C I s 1 2 3 4 5 6 7 I I I I I I I w a ( ) k p 14 13 12 11 10 9 8 I I I I I I I s 74LS04 C I 1 2 3 4 5 6 7 I I I I I I I c ( ) a a

  4. 0 p k p w 0 s b ( ) Converting to 3-input NOR gates Using Logic ICs • Example: Seat belt warning light using off-the-shelf 7400 ICs • Option 2: Use a single 74LS27 IC having 3-input NOR gates k p w s w 14 13 12 11 10 9 8 I I I I I I I s k a ( ) 74LS27 C I 1 2 3 4 5 6 7 I I I I I I I 0 c ( ) Connecting the pins to create the desired circuit a a

  5. Other Technologies 1 2 3 I I I • Simple Programmable Logic Devices (SPLDs) • Developed 1970s (thus, pre-dates FPGAs) • Prefabricated IC with large AND-OR structure • Connections can be "programmed" to create custom circuit • Circuit shown can implement any 3-input function of up to 3 terms • e.g., F = abc + a'c' O1 PLD C I programmable nodes

  6. 1 2 3 I I I O1 PLD C I programmable nodes Programmable Nodes in an SPLD • Fuse based – "blown" fuse removes connection • Memory based – 1 creates connection p r o g r ammable node Fuse based ( a ) F use "unbl o wn" fuse "bl o wn" fuse Memory based mem mem 1 0 ( b )

  7. k p s B elt W a r n k kps' p w × × w s × × × × × × PLD C I PLD Drawings and PLD Implementation Example • Common way of drawing PLD connections: • Uses one wire to represent all inputs of an AND • Uses "x" to represent connection • Crossing wires are not connected unless "x" is present 1 2 3 I I I wired AND * 3 2' I I × × O1 PLD C I • Example: Seat belt warning light using SPLD × × × 0 0 Two ways to generate a 0 term

  8. 1 2 3 1 2 3 I I I I I I programmable bit O1 O1 FF O2 O2 FF PLD C PLD C I I clk a b ( ) ( ) PLD Extensions Two-output PLD PLD with programmable registered outputs

  9. More on PLDs • Originally (1970s) known as Programmable Logic Array – PLA • Had programmable AND and OR arrays • AMD created "Programmable Array Logic" – "PAL" (trademark) • Only AND array was programmable (fuse based) • Lattice Semiconductor Corp. created "Generic Array Logic – "GAL" (trademark) • Memory based • As IC capacities increased, companies put multiple PLD structures on one chip, interconnecting them • Become known as Complex PLDs (CPLD), and older PLDs became known as Simple PLDs (SPLD) • GENERALLY SPEAKING, difference of SPLDs vs. CPLDs vs. FPGAs: • SPLD: tens to hundreds of gates, and usually non-volatile (saves bits without power) • CPLD: thousands of gates, and usually non-volatile • FPGA: tens of thousands of gates and more, and usually volatile (but no reason why couldn't be non-volatile)

  10. Technology Comparisons Full-custom Standard cell (semicustom) Gate array (semicustom) FPGA PLD Quicker availability Faster performance Lower design cost Higher density Lower power Larger chip capacity Easier design More optimized

  11. C us t om (2) (1) p r o c essor M o r e optimi z ed Easier desi g n P r o g r ammable (4) (3) p r o c essor PLD FPGA G a t e S tanda r d F ull - cus t om a r r a y c ell Technology Comparisons (1): Custom processor in full-custom IC Highly optimized (2): Custom processor in FPGA Parallelized circuit, slower IC technology but programmable Processor varieties (3): Programmable processor in standard cell IC Program runs (mostly) sequentially on moderate-costing IC (4): Programmable processor in FPGA Not only can processor be programmed, but FPGA can be programmed to implement multiple processors/coprocessors IC technologies

  12. Key Trend in Implementation Technologies • Transistors per IC doubling every 18 months for past three decades • Known as "Moore's Law" • Tremendous implications – applications infeasible at one time due to outrageous processing requirements become feasible a few years later • Can Moore's Law continue?

More Related