Transcript Document
Introduction
Programmic realisation
PC
PC
?
BUS
Micro controller
RAM
CPU
ROM
Timer
PORT
PORT
?
Hardware realisation
PCB with logical circuit composed of integral circuits.
Own micro circuit
Description
Design
Technology for designing
Micro circuits
Own micro circuit
ASIC - Application
Specific Integrated
Circuit
?
ASIC
ASIC – Application Specific Integrated Circuit
Pros:
Cons:
Cheaper to manufacture in case of large volumes;
Security;
Smaller number of components;
Greater density of components decreases loss of energy and increases
working speed.
High cost of projecting and creating the prototype in case of small
volumes;
Long duration of introduction and creation of prototype;
Difficult to alter
Design could be:
Full Custom Design – a special microcircuit is created for the product (CAD –
Computer Aided Design, Silicon Compiler);
Semicustom Design – ready-made blanks are the concrete part realising the
necessary product is designed (gate arrays, standard cells).
Programmablev logic
Demands for the elements to be programmed:
Small surface of the crystal;
Low resistance at ON and large resistance at OFF
Low capacity;
Possibility to manufacture a large number of programming elements in
the same technology as the rest of the matrix
Programming technologies:
Static RAM cells – flip-flops of static RAM
Anti-fuse – burnable joints
EPROM (Erasable Programmable Read Only Memory), EEPROM
(Electrically Programmable Read Only Memory) and Flash – ROM
elements commanded by floating gate
SRAM technology.
SRAM
trigger
SRAM
trigger
MUX
SRAM
trigger
Characteristics of the SRAM technology:
Functional blocks and joints are commanded by SRAM flip-flops;
Joint elements are located on the surface of the same crystal;
Configuration is not a destructive process;
Programming takes place after turning power on. It is possible to
reconfigure while working.
In order to configure while power is being turned on external device
with memory is needed. Configuration device is kept at the device.
SRAM elements are large (5 transistors) and they require power,
information lines, ground and selection lines;
It is possible to manufacture together with other logic in the same
CMOS technology;
The design of SRAM memory elements has been thoroughly studied.
ANTI-FUSE technology.
Metal
Amorphous silicon
Metal
Characteristics of the Anti-Fuse technology:
Modified CMOS technology and necessary stage for manufacturing
separately; a very thin isolation layer is created between the conductors;
Programming is destructive – burned joint is not restorable;
Programming takes place at tension much higher than the power, thus
auxiliary isolation layer is needed at many places;
Impossible to read the configuration file;
Suitable for manufacturing multiplexers
EPROM-itechnology
MOSFET – Metal Oxide Semiconductor Fielt Effect Transistor
p-MOS
Vgg
Gate
Silicon fixed gate
Vss
Vdd
Silicon floating gate
Source
n
Drain
n
p
n-MOS
Vgg
Gate
Silicon fixed gate
Vss
Vdd
Silicon floating gate
Source
p
Drain
p
n
Characteristics of EPROM, EEPROM and Flash technologies:
Compatible with standard CMOS technology;
The process is not destructive;
Scattering of charges as a drawback;
In case of EEPROM and Flash technology it is possible to programme
without splitting microcircuit
Terminology.
SPLD – Simple Programmable Logic Device
o ROM – Read Only Memory
o PAL – Programmable Array Logic
o PLA – Programmable Logic Array
o GAL – Generic Array Logic (Lattice)
o PLD – Programmable Logic Device
CPLD – Complex Programmable Logic Device
o EPLD – Erasable Programmable Logic
Device
o EEPLD – Electrically Erasable
Programmable Logic Device
o MAX – Multiple Array matriX (Altera)
FPGA – Field Programmable Gate Array
o LCA – Logic Cell Array
o pASIC – programmable ASIC (QuickLogic)
o FLEX, APEX (Altera)
o ACT (Actel)
o ORCA (Lucent)
o Virtex (Xilinx)
MPGA – Mask Programmable Gate Array
SPLD ja CPLD
SPLD
x1 x2
xn
...
Buffer
AND
.
.
.
OR
y1 y2
...
ym
CPLD
Connection array
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
PLA
Macrocell
Logic Block
FPGA - Field Programmable Gate Array
S/V block
I/O Cell
S/V block
I/O Cell
S/V block
I/O Cell
S/V
block
I/O
Cell
LB
Logic
Block
LB
Logic
Block
LB
Logic
Block
S/V
block
I/O
Cell
S/V
block
I/O
Cell
LB
Logic
Block
LB
Logic
Block
LB
Logic
Block
S/V
block
I/O
Cell
S/V
block
I/O
Cell
LB
Logic
Block
LB
Logic
Block
LB
Logic
Block
S/V
block
I/O
Cell
S/V block
I/O Cell
S/V block
I/O Cell
S/V block
I/O Cell
Comparison of FPGA and MPGA
.
Characteristics of FPGA:
Slower,
Smaller density;
Cheaper prototype;
Large series are remarkably more expensive;
Always possible to introduce flexible changes;
Faster into manufacturing.
Characteristics of MPGA:
Faster;
Larger density;
Expensive prototype;
Large series remarkably cheaper;
Impossible to introduce flexible changes;
Takes time to be introduced into manufacturing.
Price
MPGA
FPGA
Capacity of the series