"rickman" <gnuarm@gmail.com> wrote in message news:lr1dl7$emv$1@dont-email.me...> The point is that you turn your head one way to read the dimensions and > turn your head the other way to read the labels. The convention is to > turn the text counter clock wise or not at all, not to turn anything > clockwise. Some times this happens because an image is drawn the > correct way but then rotated to fit on the page better. The choices > then are to have some text rotated clockwise or to have some text upside > down. I guess the clockwise text is preferred. In this case the labels > did not need to be rotated at all. Also the dimensioning lines are not > drawn properly... I expect this was drawn by someone inexperienced using > conventional drawing tools.Yes, clarity would include a leader to indicate the connection between the number and the dimension. And calling it "5.0" would be even better -- makes it obvious it's not a pin number or something. I don't actually mind the colors, but the traditional complaint would be, they won't always come through e.g. on photocopies (yes, those things still exist). If it's clear in monochrome, you don't have to worry about anything else. Tim -- Seven Transistor Labs Electrical Engineering Consultation Website: http://seventransistorlabs.com
AD7793 error?
Started by ●July 25, 2014
Reply by ●July 26, 20142014-07-26
Reply by ●July 26, 20142014-07-26
On Sat, 26 Jul 2014 07:20:49 -0700, John Larkin <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote: ...snippage...> >112 pages is impressive, but it suggests that the part is very complex. In some >mixed-signal parts, like ADCs, they are way too complex. I don't need an ADC to >have a complex internal calibration subsystem; I will do calibrations in the uP >or FPGA. It's crazy to have a DAC that has pages and pages of (typically >confusing) documentation about dozens of internal registers.Yes, it is a complex part, two chips in a single package that play as one from the customer's view. Both die are accessible via the (single) SPI, and there is situation-dependent information exchange between them. There are no ADCs, but a lot of interesting pure-analog functionality, quite a few DACs, and registers and state machines to control it all. The die are not small. Often nowadays you _do_ need an ADC to have a complex internal calibration subsystem, though you may not realize it. Modern ADC architectures, especially those using fine-line processes, are often not even usable without a lot of internal self-calibration. This requires intimate knowledge of their powerful internal magic that the manufacturers are not about to divulge. Fortunately, transistors in these processes are small and cheap, so the cal engine can be put on-chip. Given everything else the cal machine does, the incremental cost of gain and offset calibration is often trivial. Of course, such calibration often only takes care of the ADC errors alone and you're still left with the rest of the signal channel to worry about, so I can understand why you don't value the cal engine very highly. As far as DACs and other things with a bazillion registers, the economics of chip design and manufacturing often come into play. You want to make a few parts that will capture as many sockets as possible; development cost is now too high to do otherwise. I agree the manufacturers certainly could spend a little more time and money (a pittance in the grand scheme of things) to de-confuse datasheets and make them actually useful. This has been my personal crusade since I first got hosed by a datasheet back around 1985. You can bet that the datasheets for my parts are as clear, accurate, and well-written as I can make them, whether I do the actual writing or, more usually, a significant amount of rewriting. It's what I would expect if I were the customer.
Reply by ●December 15, 20162016-12-15
Reply by ●December 15, 20162016-12-15
On Thu, 15 Dec 2016 11:55:29 -0800 (PST), koder <ptmisiewicz@gmail.com> wrote:>jmariano, could you upload your corrected SPI and AD`s library?The SPI interface of AD7793 is hopelessly trashed. Use ADS1247. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●December 16, 20162016-12-16
On Thu, 15 Dec 2016 12:17:30 -0500, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>On 12/15/2016 04:11 PM, John Larkin wrote: >> On Thu, 15 Dec 2016 11:55:29 -0800 (PST), koder >> <ptmisiewicz@gmail.com> wrote: >> >>> jmariano, could you upload your corrected SPI and AD`s library? >> >> The SPI interface of AD7793 is hopelessly trashed. Use ADS1247. >> >> > >I notice that you're piling in the extra chromosomes there. Kudos. > >Cheers > >Phil HobbsIf there are enough bad google links, maybe they will actually fix the stupid part. (But we know they won't.) -- John Larkin Highland Technology, Inc lunatic fringe electronics
