dbraun@cadev4.intel.com (Doug Braun ~) (01/12/88)
In the last few years, the traditional 7400 set of TTL circuits
has been implemented in newer technologies. Since my only
TTL reference is the Texas Instruments TTL Data Book, 1978 edition
("the yellow bible"), I am not sure how these new families
are used, and how they rate interms of delay, power consumption,
and availability. Could someone post a BRIEF overview of the
following types?
74ALS00
74F00
74AS00
74C00
74HC00
74HCT00
Also, if you want to post the definitive guide, you could summarize:
74H00
74L00
74S00
74LS00
7400 (Couldn't leave it out)
Did I miss anything?
Doug Braun Intel Corp CAD
408 496-5939
/ decwrl \
| hplabs |
-| oliveb |- !intelca!mipos3!cadev4!dbraun
| amd |
\ qantel /jallen@netxcom.UUCP (John Allen) (01/14/88)
In article <1552@mipos3.intel.com> dbraun@cadev4.UUCP () writes: >Could someone post a BRIEF overview of the following types? Is this brief enough? 7400 Original TTL 74F00 I dunno 74ALS00 Advanced Low-Power Schottky, improved noise immunity over LS 74AS00 Advanced Schottky 74C00 CMOS 74HC00 High-Speed CMOS, 'LS' Comparable speed 74HCT00 High-Speed CMOS, TTL Voltage Compatible 74H00 High-Speed TTL 74L00 Low-Power TTL 74S00 Schottky 74LS00 Low-Power Schottky Anyone have a rule of thumb for compatible types, incompatible types? :@) John Allen ========================================================================= NetExpress Communications, Inc. uunet!netxcom!jallen 1953 Gallows Road, Suite 300 (703) 749-2238 Vienna, Va., 22180 =========================================================================
krc@cs.purdue.EDU (Kenny "RoboBrother" Crudup) (01/15/88)
In article <634@netxcom.UUCP>, jallen@netxcom.UUCP (John Allen) writes: > 74F00 I dunno > John Allen Its for "fast". Used all the time in stuff around here. -- Kenny "_R_o_b_o_B_r_o_t_h_e_r" Crudup krc@arthur.cs.purdue.edu Purdue University CS Dept. W. Lafayette, IN 47907 The above is practically Official +1 317 494 7842 University Policy. So there.
vizard@eleazar.Dartmouth.EDU (Todd Krein) (01/15/88)
In article <634@netxcom.UUCP>, jallen@netxcom.UUCP (John Allen) writes: > In article <1552@mipos3.intel.com> dbraun@cadev4.UUCP () writes: > >Could someone post a BRIEF overview of the following types? > > > 7400 Original TTL > 74F00 I dunno I believe this is Fairchilds 'Fast' set, i.e. power hog & quick. > > Anyone have a rule of thumb for compatible types, incompatible types? > As for pinouts, I think they're all mix'n match.... You're gonna have problems with different driving ranges (74ls00 can drive 10 more 74ls00, but only one or two 7400's), and if the timing is critical... Well, hell. Anything could happen. Todd Krein
johne@astroatc.UUCP (Jonathan Eckrich) (01/16/88)
Just some brief additions. In article <634@netxcom.UUCP> jallen@netxcom.UUCP (John Allen) responds: > >7400 Original TTL Slow and lots of power. >74F00 I dunno F stands for Fast. Made by Fairchild, Signetics, and Motorola. My favorite choice for speed, power, price, ease of use. >74ALS00 Advanced Low-Power Schottky, improved noise immunity over LS Comparable to F-parts, made by TI, so don't trust availablity. >74AS00 Advanced Schottky Comparable to ALS, but faster, and needs more power. >74C00 CMOS Very low power, slower, sensitive to static discharge, wide range of supply voltage. >74HC00 High-Speed CMOS, 'LS' Comparable speed >74HCT00 High-Speed CMOS, TTL Voltage Compatible >74H00 High-Speed TTL >74L00 Low-Power TTL Slower than original, almost as old. >74S00 Schottky Predecessor to LS, AS, ALS. >74LS00 Low-Power Schottky > >Anyone have a rule of thumb for compatible types, incompatible types? > Sure. Plug them together, and if you don't smell smoke, they work. ;-) Actually, I don't have a rule a thumb to use. I look in the spec sheets to see if the chip doing the driving has (near) equivalent voltage and current capabilities to that of the receiving chip. -- ------------------------------------------------------------------------- Jonathan Eckrich | (rutgers, ames)!uwvax!astroatc!johne Astronautics Technology Center | ihnp4!nicmad!astroatc!johne Madison, WI | (608) 221-9001
phd@SPEECH1.CS.CMU.EDU (Paul Dietz) (01/19/88)
In article <7928@eleazar.Dartmouth.EDU> vizard@eleazar.Dartmouth.EDU (Todd Krein) writes in reference to TTL families: >As for pinouts, I think they're all mix'n match.... Oh! I don't think so! I don't have my data books next to me, but I'm pretty sure that some of the 74L series had unusual pinouts. I'll go check, but in the interim, does anyone want to comment? Paul H. Dietz ____ ____ Dept. of Electrical and Computer Engineering / oo \ <_<\\\ Carnegie Mellon University /| \/ |\ \\ \\ -------------------------------------------- | | ( ) | | | ||\\ "If God had meant for penguins to fly, -->--<-- / / |\\\ / he would have given them wings." _________^__^_________/ / / \\\\-
max@trinity.uucp (Max Hauser) (01/19/88)
In article <669@PT.CS.CMU.EDU> phd@SPEECH1.CS.CMU.EDU (Paul Dietz) writes: >In article <7928@eleazar.Dartmouth.EDU> vizard@eleazar.Dartmouth.EDU >(Todd Krein) writes in reference to TTL families: >>As for pinouts, I think they're all mix'n match.... >Oh! I don't think so! I don't have my data books next to me, >but I'm pretty sure that some of the 74L series had unusual >pinouts. I'll go check, but in the interim, does anyone want to >comment? Who could turn down such an invitation! (Not me, anyway) They shore did have varying pinouts across the "compatible" 54/74 /L/H series. Also, the standardization of corner power on DIPs came after quite a number of the basic 54/74 designs had been released. So you got some later members of the family that were identical copies of earlier members except with bonding pads laid out so they could be bonded with corner power pins (74107 vs. 7473? That comes to mind, but mind is sometimes faulty). There must be other readers who can remember the days (late 60s - early 70s) when the TI 54/74 family was competing for its eventual preeminence against its rivals, like the Sylvania SUHL I/II and the Fairchild 9000 "CCSL" series. (Who remembers what SUHL and CCSL stand for?) I don't suppose many SUHL or CCSL TTL chips are still being specified, but they had their own clever ideas about power pins too ... Max Hauser / max@eros.berkeley.edu / ...{!decvax}!ucbvax!eros!max UCB EECS -- IC Design
henry@utzoo.uucp (Henry Spencer) (01/24/88)
In practical terms, ignoring the technological details, this is my view
of the families (NB I am not a giant corporation, which influences my
views on things like availability and backward compatibility):
74 The original. Speed good, power consumption fair. Effectively
obsolete now; use 74LS or later, except for a *very* few oddball
functions like 7407 which are hard to find in newer families.
74H Modification of 74 for higher speed, at the cost of higher
power consumption. Very obsolete; use 74F.
74L Modification of 74 for lower power, at the cost of lower speed.
Very obsolete; use CMOS.
74S Later modification of 74 for even higher speed, at some cost in
power consumption. Effectively obsolete; use 74F.
74LS Combination of 74L and 74S, for speed comparable to 74 with lower
power consumption. Best all-round TTL now, widest variety of
devices.
74F Fast as blazes, power not too bad. The clear choice for high
speed in TTL. Availability and prices generally good.
74AS Failed competitor to 74F. May be worth using if it does something
not yet available in 74F.
74ALS Possible replacement for 74LS. Generally souped up. Still fairly
new, availability and prices possibly a problem.
74C Fairly old family, CMOS devices with TTL pinouts. Competed with
4000 series, not too successfully. Obsolete; use 4000 or newer
CMOS 74 families.
4000 (Thrown in as the major non-74 non-ECL logic family.) The old CMOS
family, still viable because of *very* wide range of devices, low
power consumption, and wide range of supply voltages. Not fast.
Very forgiving and easy to work with (beware static electricity,
but that comment applies to many other modern logic families too).
There are neat devices in this family that exist in no other. The
clear choice when speed is not important.
74HC A new attempt at 74-pinout CMOS. Fast compared to old CMOS, power
consumption often lower than TTL. Possibly a good choice for
general-purpose logic, assuming availability and affordability.
CMOS logic levels, *not* TTL ones. Beware very limited range of
supply voltages compared to older CMOS, also major rise of power
consumption at faster speeds.
74HCT 74HC with TTL logic levels. Much the same comments as 74HC. Read
the fine print on things like power consumption -- getting TTL
levels out of CMOS involves some compromises, I think.
10000 (Thrown in for speed freaks.) The low end of ECL. Various sources
claim that it is *easier* to work with than super-fast TTL for
serious high-speed work. Less forgiving, though: read and follow
the rules or it won't work. Availability to hobbyists limited,
can be expensive.
As for compatibility between families: the 74 families (except 74C and
74HC) are all more or less logic-level compatible, but how many 74X devices
you can drive from one 74Y output varies enormously with X and Y. You just
have to read the specs and do the arithmetic. 74C and 74HC are compatible
with the others with a bit of hassle. 4000 compatibility can be a bit of
hassle or a lot of hassle depending on what supply voltage 4000 is using.
10000 to anything else is considerable hassle.
Me? I use 4000 and 74LS with a sprinkling of 74F. 74HC[T] and 10000 are
interesting but I haven't used either significantly yet.
--
Those who do not understand Unix are | Henry Spencer @ U of Toronto Zoology
condemned to reinvent it, poorly. | {allegra,ihnp4,decvax,utai}!utzoo!henrycreps@silver.bacs.indiana.edu (Steve Creps) (01/25/88)
I'm surprised nobody has mentioned the 54LS series yet.
munir@vcvax1.UUCP (munir) (01/29/88)
> > I'm surprised nobody has mentioned the 54LS series yet. Because the 54 series are essentially the same as the 74 series except that they are mil spec chips