Alt-BEAM Archive

Message #09823



To: beam@sgiblab.sgi.com
From: "Dane Gardner" dane@foremostspring.com
Date: Sat, 5 Feb 2000 07:01:10 -0800
Subject: [alt-beam] Re: hc, hct, ac, act



content-transfer-encoding: quoted-printable


Where is it?
-William

Well, you know what? I can't find it myself...so I'll just repost it. Her=
e you go...



Sure, here's my notes for a test I had a couple of semesters ago.

74 (usually) means that it is a commercial chip. As opposed to the militar=
y 54 series. The 54's are WAY more expensive and are not worth it. The di=
fference? The military chips have a broader power rating, they can handle =
extreme temperatures (high and low), and aren't supposed to be as static se=
nsative as the 74's. Then there's the old 4000 series that is just a low s=
peed CMOS. And the BiCMOS that combines CMOS and TTL (not comatabilities, =
but actual technology within the chip itself).

There are a whole bunch of other chip styles...but I've only run accross th=
em once or twice in ten years now, so don't worry to much about them. =


The real difference between CMOS and TTL is in performance. Like propagati=
on delay (switching speed), noise immunity, power disipation, static sensat=
ivity, etc. A lot of the more advanced TTL is faster, but SUCKS down the p=
ower (the S series wasn't even worth it unless it was plugged into a wall).=
In these notes, I generally went from oldest to newest tech, which usuall=
y means that its slow to fastest.

Complementary Metal-Oxide Semiconductor (CMOS) circuits are generally imple=
mented with a type of Field-Effect Transistor. Some of their flavors are a=
s follows:

5V Series:
HC -- High speed CMOS
HCT -- High speed CMOS with TTL compatability
AC -- Advanced CMOS
ACT -- Advanced CMOS with TTL compatability
AHC -- Advanced High speed CMOS
AHCT -- Advanced High speed CMOS with TTL compatability

3.3V Series:
LV -- Low Voltage CMOS
LVC -- Low Voltage CMOS (same as above, just a next generation)
ALVC -- Advanced Low Voltage CMOS

BiCMOS:
BCT -- BiCMOS
ABT -- Advanced BiCMOS
LVT -- Low Voltage BiCMOS
ALB -- Advanced Low Voltage BiCMOS

Transistor-Transistor Logic (TTL) is implemented with bipolar junction tran=
sistors. Some TTL series packages:

74 or 54 no letters -- straight TTL
S -- Schottky TTL
AS -- Advanced Schottky TTL
LS -- Low power Schottky TTL
ALS -- Advanced Low power Schottky TTL
F -- Fast TTL


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>
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Where is it?
-William

Well, you know what?  I can't find it mysel=
f...so =

I'll just repost it.  Here you go...

 

 

 


Sure, here's my notes for a te=
st I had =

a couple of semesters ago.

 

74 (usually) means that it is =
a =

commercial chip.  As opposed to the military 54 series.  The 54's=
are =

WAY more expensive and are not worth it.  The difference?  The =

military chips have a broader power rating, they can handle extreme tempera=
tures =

(high and low), and aren't supposed to be as static sensative as the 74's.&=
nbsp; =

Then there's the old 4000 series that is just a low speed CMOS.  And t=
he =

BiCMOS that combines CMOS and TTL (not comatabilities, but actual technolog=
y =

within the chip itself).

 

There are a whole bunch of oth=
er chip =

styles...but I've only run accross them once or twice in ten years now, so =
don't =

worry to much about them. 

 

The real difference betwe=
en CMOS =

and TTL is in performance.  Like propagation delay (switching speed), =
noise =

immunity, power disipation, static sensativity, etc.  A lot of the mor=
e =

advanced TTL is faster, but SUCKS down the power (the S series wasn't even =
worth =

it unless it was plugged into a wall).  In these notes, I generally we=
nt =

from oldest to newest tech, which usually means that its slow to =

fastest.

 

Complementary Metal-Oxide Semi=
conductor =

(CMOS) circuits are generally implemented with a type of Field-Effect =

Transistor.  Some of their flavors are as follows:

 

5V Series:

HC -- High speed CMOS DIV>
HCT -- High speed CMOS with TT=
L =

compatability

AC -- Advanced CMOS V>
ACT -- Advanced CMOS with TTL =

compatability

AHC -- Advanced High speed =

CMOS

AHCT -- Advanced High speed CM=
OS with =

TTL compatability

 

3.3V Series:

LV -- Low Voltage CMOS<=
/DIV>
LVC -- Low Voltage CMOS (same =
as above, =

just a next generation)

ALVC -- Advanced Low Voltage =

CMOS

 

BiCMOS:

BCT -- BiCMOS

ABT -- Advanced BiCMOS<=
/DIV>
LVT -- Low Voltage BiCMOS T>

ALB -- Advanced Low Voltage =

BiCMOS

 

Transistor-Transistor Logic (T=
TL) is =

implemented with bipolar junction transistors.  Some TTL series =

packages:

 

74 or 54 no letters -- straigh=
t =

TTL

S -- Schottky TTL

AS -- Advanced Schottky =

TTL

LS -- Low power Schottky =

TTL

ALS -- Advanced Low power Scho=
ttky =

TTL

F -- Fast =

TTL




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