
Unsung Beauty of Analog Devices Datasheets - neilpanchal
https://neil.computer/notes/analog-devices-datasheets/
======
TFortunato
Former Analog Devices employee here. I used to write programs and that
collected all of the data for the data sheets. We would take all of these
complex measurements on a part in just seconds using some pretty fancy test
equipment. It definitely taught me a lot / inspired me to learn more about
programming as a a fresh-out-of-school EE

Definitely happy to see some data sheet love ..chip companies are definitely
in a whole different world when it comes to documentation, compared to the
software world I'm now in!

~~~
zerogvt
"..chip companies are definitely in a whole different world when it comes to
documentation, compared to the software world I'm now in!"

Makes sense though. SW is a much more agile/faster iterations artifact than
HW. Documentation is very hard to keep pace in this env, so much so that
people are actually trying to infer it automatically from the -ever changing-
code.

~~~
jlg23
Your wording shows the difference very well: ~"Documentation that we have to
keep updating" vs. "datasheet" (a specification).

------
jumpingmice
Data sheet culture at these old-line semiconductor companies - ADI, TI, Linear
- descends from the fact that you used to hold it in your hand and read it on
paper. When I was in that field we went to the company library to read
datasheets because ISO9001 required the company librarians to record which
revision of which part an engineer read at what date and time. And it was
partly sales literature because you'd be flipping through a bound volume of
ADI's current parts looking for something suitable.

If you really want to get the whole experience then I urge you to print these
out. The graphics are high-resolution.

~~~
squarefoot
Those were also the days when a radio or TV set came with full schematic
diagram in the manual, and IC data sheets also contained the full internal
schematics of a part rather than just a block diagram or a simplified
schematic without parts values.

~~~
jumpingmice
Sounds like you’re just a little older than me :-)

~~~
squarefoot
Possibly yes, I was just a kid in the mid 70s and have memories of those
enormous books filled with TV schematics the repairman had at his shop, also
every TV was accompanied by its own one. TV manufacturers kept distributing
schematics until mid to late 80s, then stopped. Unfortunately back then
scanners and the needed storage were almost science fiction, and the format
would have hard to scan anyway due to the huge page sizes, so most of those
books are either lost or sold at absurd prices online as vintage.

------
exmadscientist
A couple recent exceptional datasheets I've come across include ADI's ADA4530
[1] and Renesas/Intersil's ISL28110 [2]; both, coincidentally, happen to be
for regular old op-amps. The ADA4350 datasheet in particular is absolutely
stunning and proof that the old ways are not completely gone. The ISL28110
datasheet is notable when, in an era when I all too often need to read between
the lines to determine the type of _input transistor_ used (seriously, guys,
it's not hard to show and there are only six possibilities so it's not like
you're giving away secrets here), they show a _complete device model_.

That said, I still miss LTC, NSC, and the pre-Renesas Intersil.

[1]: [https://www.analog.com/media/en/technical-
documentation/data...](https://www.analog.com/media/en/technical-
documentation/data-sheets/ADA4530-1.pdf)

[2]:
[https://www.renesas.com/us/en/www/doc/datasheet/isl28110-210...](https://www.renesas.com/us/en/www/doc/datasheet/isl28110-210.pdf)

~~~
neilpanchal
Thanks for sharing, old ways are definitely not gone but eroding away sadly.

One of things I find amazing about the datasheet culture is that there is
minimal marketing bullshit (although there are exceptions, I am looking at
you, ST Electronics). Skimming through ADA4350 datasheet, I see no trace of
any kind of trickery that we usually see in other industries. Datasheets are
_the_ thing people look for and since the audience is engineers, they won't
put up with marketing nonsense. As a consequence, there is almost perfect
objectivity in selling a product - based on features, performance,
operability, etc. Since decision makers are engineers, data and specifications
prevail.

~~~
TFortunato
(Full disclosure, former AD employee)

In particular with precision Analog / mixed-signal / RF, there is a real
recognition that there is no perfect Amplifier / Converter / Black Box X, that
will satisfy all applications. That all abstractions (and inputs) are leaky, a
wire is never just a wire, ground is never ground, noise exists, etc. That the
reality is that there are myriad tradeoffs to be made depending on what you
want to do, and the best way to be successful is to acknowledge that fact from
the start without any bullshit; And as a supplier to tell you exactly what
those real-world tradeoffs are and help guide you towards being successful.

To their credit the applications engineers and even sales folks when I was
there were just as happy to sell you a $.05 "jellybean", as they were to sell
the latest precision laser-trimmed FancyAmp if that's all you needed because
they were like minded engineers too, and at the end of the day, building
something that did the job it needed to was satisfying.

(Plus, as anyone whose done consumer/ high-volume electronics will tell you,
BOM cost is it's own variable in the optimization space that can lead to some
creative design choices!)

------
scoutt
Kind of a rant, so forgive me for venting out :)

An untold truth is that datasheets are also the terrain for disputes with tech
support. That is, there is a whole team of people called Application Engineers
in said companies dedicated to support, that basically knows very little about
the practical side of the product and all they do is to read datasheets, just
in case there are engineers out there that design products without studying
it.

So in order to pass the first (and usually not very helpful) line of support
you better study the datasheet because it will be a sort of "legal" document
you will have opened in your screen for the next week, until the application
engineer gives up and connects you with someone who knows the product.

Regarding the quality of documentation, yes, nobody beats old monsters like
AD. In regards of reference designs... AD is used to give you a 10"x10" board
to evaluate a tiny little component; let's say a battery charger. Of course
the reference design board has traces of the width of a thumb, very big gold-
plated connectors for the power supply, etc. So when you go and integrate the
little component in your wrist watch and it doesn't work, the application
engineer will go with: "yeah, your design is not much like the reference
design, so it's kind you will run into trouble.".... Imagine the rage...

------
ash
Many years ago I was on a team designing a "smart sensor" box. The heart of it
was an integrated precision A/D + 8051-compatible microcontroller chip from
Analog Devices:

[https://www.analog.com/media/en/technical-
documentation/data...](https://www.analog.com/media/en/technical-
documentation/data-sheets/ADUC814.pdf)

None of us has ever worked with microcontrollers before. It was my first ever
job out of school. I don't think we would be able to deliver the product if
the chip datasheet was not awesome. It had everything. Memory organization,
registers, peripherals, board layout and grounding recommendations, ADC
driving, etc.

Thank you, Analog Devices engineers.

------
ISL
When teaching students about datasheets, I generally pull up an AD datasheet
and state, "This is what a good datasheet should look like."

They're not the only makers of good datasheets, but they're very consistent.
(and many of their chips are awesome)

~~~
vvanders
Yeah, as someone who's self taught AD and Linear data sheets were always
awesome and a great source of information.

------
bacon_waffle
Linear Technology's AN47 "High Speed Amplifier Techniques" is my favourite
document in this category. It is both nicely presented, and a great resource
for high performance electronics:

[http://www.linear.com/docs/4138](http://www.linear.com/docs/4138)

~~~
gaze
All of Jim Williams' app notes are absolutely top notch.

~~~
cushychicken
Williams definitely wrote his stuff for a different generation of engineer - a
generation where not everyone had access to the internet, and it behooved LTC
to pack as much info into one document as possible.

The mark of just how good AN-47 is that, even in the age of the internet, it's
_still_ one of the best go-to guides on high speed opamp design and the
attendant/surrounding challenges. Particularly concerning proper oscilloscope
techniques for accurate measurements of high speed circuits.

------
kartikkumar
I have "datasheet-envy".

I'm one of the co-founders at satsearch [1], where we're working on fixing
procurement in the space industry. We're constantly battling shitty
datasheets.

As a space engineer, I found it infinitely frustrating to work with flyers
that suppliers provide on their website, that also double-up as preliminary
datasheets. They're messy, inconsistent, and subject to whatever the supplier
thinks their buyer might want to know.

We wrote a blog article about the mess that exists in the space industry [2],
and a follow-up about what we think can be done to improve this through
Electronic Data Sheets (EDS) [3].

The EEE industry seems streets ahead in this regard, which is perhaps
primarily down to strong commercialization and rapid growth of the market over
the past 20 years. I think with companies like Octopart [4] making it patently
obvious who does a good job of supporting engineers, it might also have pushed
suppliers to improve their documentation.

I'm curious though about the consistent use of PDFs. I understand from a
usability point of view that they're great for documents, but I would have
imagined that the EEE industry would have started distributing "smart
documents".

To give you an example, the AD datasheet in this article includes a number of
high-res graphs: why has the sector not moved to the point where these graphs
are interactive elements that you can zoom into, programmatically read off of,
export data from, etc.? The way I look at it, a Juypter notebook or something
similar would be an awesome way to share datasheet content, allowing much more
interactivity.

Anyone with any thoughts as to why datasheets haven't progressed in that
direction?

[1] [https://satsearch.co](https://satsearch.co)

[2] [https://blog.satsearch.co/2018-02-21-building-better-
datashe...](https://blog.satsearch.co/2018-02-21-building-better-datasheets-
for-space-mission-design.html)

[3] [https://blog.satsearch.co/2018-01-23-the-challenges-of-an-
en...](https://blog.satsearch.co/2018-01-23-the-challenges-of-an-engineer-in-
the-new-space-age.html)

[4] [https://www.octopart.com](https://www.octopart.com)

------
userbinator
On the other hand, TI's datasheet quality seems to have gone downhill, ST and
Infineon's has always been horrible, and Broadcom is infamous for not
releasing them at all.

~~~
taneq
Back in the day the saying was "lies, damn lies, and datasheets." The
relatively rare companies that put out good datasheets were my heroes.

------
RachelF
Most electronic engineering component-related documentation is good. It has a
long history tracing back through National Instruments.

Intel's 80386 documentation was superb.

~~~
HeyLaughingBoy
I believe you mean National _Semiconductor_

NI is an instrumentation board maker that got started in the 80's.

------
cushychicken
One other interesting repository of design knowledge: Texas Instruments'
reference design catalog.

TI will _give_ you the plans to build all sorts of machines and gizmos using
their chips. ATMs, industrial robots, blood oxygen meters, even oscilloscopes
- you can find detailed design information (schematics, BOMs, layouts, etc) on
TI's website, free of charge.

~~~
bombledmonk
A huge amount of manufacturers offer designs here's a curated compilation....
[https://www.digikey.com/reference-
designs/en](https://www.digikey.com/reference-designs/en)

~~~
cushychicken
True. I just like TI's as an example because they cover so many use cases and
market verticals.

------
btashton
I owe a great deal to National Semiconductor and their application notes.
Prior to college I tought myself a lot of what I know about analog design from
this handbook [0]. I remember in middle school calling up the support line and
having an extremely patient applications engineer walk me through my design
and point me at resources to learn. He always answered my emails, even though
I'm sure he had more important questions to answer. I tried several years ago
to track down the emails to contact him again and thank him, but those emails
seem long gone.

[http://mirror.thelifeofkenneth.com/lib/electronics_archive/N...](http://mirror.thelifeofkenneth.com/lib/electronics_archive/NationalSemiconductorLinearApplicationsHandbook1994_text.pdf)

------
eisen
IMO - This article is an over simplification. Data sheets need to be book
worthy documentation due to the behavior of complex semiconductors. I believe
Datasheets are law abiding documentation? If something is out of spec or out
of characteristics is is considered faulty which means loss of money or
competitors can get in.

What I'm really interested is in what peoples opinions are regarding the
navigation of content and material of these large scale Semiconductor Sites.
They have 50k plus products which are all very complicated and specific to a
use-case. I find there is a constant struggle to route people to the right
solution especially when engineers can use different parts in new creative
ways. ADI, Texas Instruments, and Maxim all fall in this boat.

~~~
pininja
> Datasheets are law abiding documentation?

Ideally true, but in practice I’ve seen certain performance claims (such as
battery cell capacity degradation in a battery data sheet) aren’t accurate or
depend a lot on your application. If they are reputable, I assume they are
trying to estimate an honest average.

Navigating the sites are challenging when I don’t already know which part I
want, for sure. I wish there were better ways to explore sites for certain
keywords in a data sheet.

~~~
nitrogen
Do search engines like Octopart or Digikey help?

~~~
joshvm
Digikey has one of the better search engines, not least because you get
preview thumbnails of almost everything, and you can search in single unit
quantities. It also has some intelligence when filtering parts by value (eg
Leds by wavelength).

The problem is usually knowing the names of things, and eventually you learn
what keywords to search for eg 2row 10way for a 2x5 connector. Everything is
mostly standardised.

Octopart is best for finding stock, I wouldn't use it to locate a new part.

For finding new chips, like random sensors, the best way is to trawl the major
IC websites (Ti, Max, etc) and see what pops up. You can still get samples
from most of these places, and of quite expensive parts too.

------
madengr
ADI has gone down hill. For example, the HMC6300 datasheet is crap, having
wrong register values, and lacking the interfacing details. Hittite, prior to
ADI, would have never had a poor data sheet like that. The ADI web site also
stinks, compared to what was Linear Technology.

------
m463
I believe the Signetics 25000 series 9C46XN document is arguably the pinnacle
of datasheets:

[http://www.repeater-
builder.com/molotora/gontor/25120-bw.pdf](http://www.repeater-
builder.com/molotora/gontor/25120-bw.pdf)

~~~
bombledmonk
Oh good, someone posted this! By far the best datasheet ever written.

------
gumby
The data sheets of AD, National, TI et al have also followed a pretty standard
format in terms of layout, order of descriptions etc (something that I have
always assumed predated semiconductors). This helps make them particularly
useful.

------
amelius
Reminds me of the cartoons in Tektronix manuals:

[http://w140.com/tekwiki/wiki/Tektronix_Cartoons](http://w140.com/tekwiki/wiki/Tektronix_Cartoons)

I think it was recently discussed on HN.

------
jdblair
To really understand what the author is getting at it helps to have some
experience with lower quality data sheets from other manufacturers. Take, for
example, the WS2801, a popular LED driver chip from World Semi[1]. All of the
necessary information is there (I used it to successfully wire them up and bit
bang the LED colors) but it's just not pretty. The blue header is jarring and
the graphs are screenshots from a scope.

[1] [https://cdn-shop.adafruit.com/datasheets/WS2801.pdf](https://cdn-
shop.adafruit.com/datasheets/WS2801.pdf)

------
peter_retief
They do make beautiful documentation, so clear concise and well ordered. Would
be nice to see who the authors are but I suspect they might be introverts.
Certainly show a love for their work

------
readingnews
"hehehe, I remember my first krabbie patty".

Looks like someone stumbled across a data sheet, and never read any before.
Almost all of them look like that. Ti, NatSemi, ON, DIODES-inc, NEC, Toshiba,
etc, etc. Ti and National Semiconductor used to be great reading for new
engineers.

------
klyrs
I really love sites full of gorgeous, detailed images that block my browser's
zoom feature. /s

~~~
neilpanchal
There is no JS or anything on the page (besides what Ghost blog puts out for
metadata). I am getting 99/100 on Google page speed test as well.

I tried zooming in on images using iPhone X / Safari and there is no issue.
Are you sure something isn't wrong at your end?

~~~
klyrs
I'm using firefox on android, but the problem is here:

<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-
scale=1.0, maximum-scale=1.0, user-scalable=no" />

~~~
neilpanchal
Thanks! I fixed it and it should be scalable now.

------
ttlei
I used to worked at Intel as a design engineer and I had to look through data-
sheets to find the ICs with features and specs that I needed for the design.

