Saleae Logic Pro 8 quick teardown - Page 1
Forum section: electronics / testgear

author: ttt
author_rank: Regular Contributor
timestamp: October 08, 2014, 08:24:08 am
content: Hi,got the brand new Saleae Logic Pro 8 logic analyzer today and thought to do a quick teardown.https://www.saleae.com/goes into details about what's new compared to the old models, which is primarily USB 3.0 (for the Pro models) and analog support.Digital:Sample Rate (max) 500 MS/sFastest Digital Signal 100 MHzSupported Logic Levels 1.2V - 5.5VAnalog:Sample Rate (max) 50 MS/sBandwidth (-3dB) 5 MHzNumber of bits 12 bitsInput Voltage Range -10 V to 10 VSINAD 62 dB or betterThe analog portion is nothing to write home about. I guess it could be useful if you have no scope or want store gigabytes of data. I have it sampling a 2Mhz -1V/1V square wave in one of the pictures below. The software remains pretty sluggish otherwise when processing data, especially with the now additional data it has to deal with when running at the max 500MS/s. I am pretty happy though since it has enough throughput now where I can debug some of my higher speed SPI MCU stuff. The 500MS/s persists with up to 4 digital channels and goes down to 100MS/s when you sample 5 channels or more. Build quality is good (apart from a couple of small scratches on the PCB, see below), the probe cables are much higher quality compared to the old Logic16 I have.Now, there are some problems with the software which is a little too dumbed down IMO. While the hardware can now handle -10V...10V input voltages there is no way to customize threshold voltage levels for the digital sampling part from what I can see apart from 600mV / 900mV / 1.65V. Slightly disappointing and maybe a limitation in hardware. In theory the hardware should be able to handle USB 2.0 high-speed but the 400mV voltage levels stand in the way (and probably would be confused by the USB2.0 chirping at 3V).

author: george graves
author_rank: Super Contributor
timestamp: October 08, 2014, 09:02:02 am
content: I can't comment on the specs(the original more than meets my little needs when I borrowed one)....but hats off to amazing looking board and case.I think they are playing around with making a "scope" of some kind. Or at least they have kinda teased the idea.They have a great bloghttp://blog.saleae.com/- too bad most of the early posts were lost, some great early start up stuff - iit was fun watching them go from an idea to shipping.

author: MarkL
author_rank: Unknown
timestamp: October 13, 2014, 08:42:53 pm
content: Received my Logic-16 Pro today. There's not much to add to ttt's description except that it has twice the channels. Pic below.It has quite a bit of heft due to the thick, machined aluminum enclosure. It seems a bit overdone, but maybe they needed that for heat dissipation. The probe leads are nicely labeled, flexible, and are comparable to the quality on the very first Logic (plain) units. Black grabbers are provided for all ground and signal leads. It would have been nice to have colored ones. Board build quality is first class.The SW is still in beta and it's a little unstable on Linux (probably because of my distro, Centos 6.5).A few short tests shows that everything is working on the 8 lower channels, but the SW will not allow use of the upper 8 at all because I don't have USB 3.0 (yet). My expectation was that everything would work at lower capture rates on USB 2.0. Case opened with Saleae to see if this is a permanent limitation.

author: miguelvp
author_rank: Super Contributor
timestamp: October 14, 2014, 03:01:25 am
content: http://sigrok.org/wiki/Main_Pagesupports both I believe, I don't have one and I really don't know how capable that software is, but they do have a lot of details on the devices themselves.http://sigrok.org/wiki/Saleae_Logichttp://sigrok.org/wiki/Saleae_Logic16

author: true
author_rank: Frequent Contributor
timestamp: October 14, 2014, 04:22:37 am
content: These are Logic Pro units, not the older Logic units.This is a new product.

author: artag
author_rank: Super Contributor
timestamp: October 15, 2014, 11:16:15 pm
content: I also got a pro-8, having previously owned the original. Glad I didn't get one during the period when the probes were cost-reduce : i've had cheap micrograbbers from seeed and they were nasty. The original ones on Logic were ez-hook (also the grabbers used by HP), these have no moulded name but seem of similar quality.Still a beautiful package, even if not as attention-grabbing as the Logic, which was incredibly tiny. These are merely ordinarily tiny.Some good points on the pro analog inputs : they're 12 bit, unlike many such devices, and bipolar (the Logic 8 isn't). It emains to be seen whether they're useful for much, but it's very much better for putting in a tool bag than one of the chinese usb scopes. Looking forward to getting it running on USB3.

author: MarkL
author_rank: Unknown
timestamp: October 16, 2014, 12:23:55 am
content: Still wading through bugs in the beta version for Linux, which is the only version that supports the Pro series.I was anxious to try out the upper 8 channels on my Pro-16, which require USB 3.0, so I ordered a USB 3.0 card and then I bumped into this popup:QuoteOuch!"OK?" Well, not really. But I guess I'll be waiting some more.

author: MarkL
author_rank: Unknown
timestamp: October 16, 2014, 12:27:51 am
content: Quote from: MarkL on October 13, 2014, 08:42:53 pmAnswer from Saleae is that the amount of power required for all 16 channels is beyond USB 2.0's capabilities. So they disable the upper 8 channels. They plan to add an option to force them all on anyway and then it will be up to the user to make sure the device is supplied with enough power, such as through an intervening powered hub.

author: alank2
author_rank: Super Contributor
timestamp: November 01, 2014, 09:25:53 pm
content: Quote from: MarkL on October 16, 2014, 12:27:51 amI saw that note on their site as well. I love how pretty their pcb and enclosure is.