Rigol's New DHO800 Oscilloscope unbox & teardown

[mawyatt]

P.S my tek2465 died today, spark noises and smoke cloud, I wasn't completely surprised . I guess it couldn't handle the mental pressure of a third oscilloscope. 

Hopefully just those pesky "Rifa" time bombs!!

Best,

[Fungus]

You added a carrying handle to your siggen? 

[Andromedoh]

on to DHO800's LiteOn PSU... (beware this is non-reversible invasive action to tear down)
only 3 wires to USB3 connector, black (gnd), blue?, red?. so what kind of PD is this? when not connected to DSO, blue is 4.11V, red is 0V, once connected whether on or off, blue is 1.68V, red is 15V. i tried $1.50 USB3 DC pigtail to power DSO from SMPS PSU... if 12V, current is 3A, if 15V, current is 2.37A during operation (at boot up , its half that). so its a preferable fact that PSU/DSO is not that complicated to handle/diy, fwiw...

Do you have any images of the PSU board? Does it have all the proper filtering and decent quality components?

[Mechatrommer]

You added a carrying handle to your siggen? 

thats the small part. the bigger part why its there is at the back of the siggen... https://www.eevblog.com/forum/testgear/uni-t-utg932utg962-200msas-function-arbitrary-waveform-generator-220394/msg4434787/#msg4434787

on to DHO800's LiteOn PSU... (beware this is non-reversible invasive action to tear down)
only 3 wires to USB3 connector, black (gnd), blue?, red?. so what kind of PD is this? when not connected to DSO, blue is 4.11V, red is 0V, once connected whether on or off, blue is 1.68V, red is 15V. i tried $1.50 USB3 DC pigtail to power DSO from SMPS PSU... if 12V, current is 3A, if 15V, current is 2.37A during operation (at boot up , its half that). so its a preferable fact that PSU/DSO is not that complicated to handle/diy, fwiw...

Do you have any images of the PSU board? Does it have all the proper filtering and decent quality components?

no i dont have. the heatsink enclosing the pcb is tightly glued to the pcb and components, so i'm not intending to damaging all those, otherwise restoring them will be messy. i just assume LiteOn did their good job, i only want to know what wires that goes to the USB3 connector.

[Fungus]

so what kind of PD is this?

PD is only three wires AFAIK. Two for power and one for serial comms.

[DaneLaw]

USB-PD needs a minimum of three wires. VBUS, CC1, or CC2 and GND also highlighted on the board https://www.eevblog.com/forum/testgear/rigols-new-dho800-oscilloscope-unbox-teardown/?action=dlattach;attach=1907013;image
Placement in a TypeC connection.
https://www.allaboutcircuits.com/uploads/articles/Fig1m11292018.png

[Howardlong]

on to DHO800's LiteOn PSU... (beware this is non-reversible invasive action to tear down)
only 3 wires to USB3 connector, black (gnd), blue?, red?. so what kind of PD is this? when not connected to DSO, blue is 4.11V, red is 0V, once connected whether on or off, blue is 1.68V, red is 15V. i tried $1.50 USB3 DC pigtail to power DSO from SMPS PSU... if 12V, current is 3A, if 15V, current is 2.37A during operation (at boot up , its half that). so its a preferable fact that PSU/DSO is not that complicated to handle/diy, fwiw...

Only 3 wires is acceptable, as only one CC is required when terminated with a plug: it's up to the receptacle end to figure out which is active by terminating both CC1 and CC2 separately, each with a 5.1k pull down, and measure which one has a corresponding pull up, indicating it's the right CC line to negotiate capabilities and coordinate settings.

"Figure 2-2 illustrates the comprehensive functional signal plan for the USB Type-C plug. Only one CC pin is connected through the cable to establish signal orientation"

(Ref for the nerds: USB Type-C Cable and Connector Specification Release 2.2, Section 2.1 pp 31-32 https://www.usb.org/document-library/usb-type-cr-cable-and-connector-specification-release-22).

Here's my LiteOn, together with a capture of the capabilities, captured with a Cypress CY4500 protocol analyser (hooked up to a PD trigger board) and corresponding scope traces. These were taken at PD trigger insertion.

I didn't take any current measurements, but I did measure the claimed voltage domains, and all were supported when I selected each one with the PD trigger.

The Cypress CY4500 is a very useful tool for PD debugging, it bridges the gap between a scope and LA as the protocol decoder on the CY4500 is generally more useful than any scope PD decoder I've encountered such as in the MSO3000T, unless you're interested in the weeds at the symbol level, as the CY4500 doesn't expose samples at high enough resolution in its time domain trace to be able to see the individual symbols (although it does decode perfectly).

Setting up the CY4500 software with the right firmware & software versions to begin with is a PITA: you need to install the original v1.0.0 PC software first to update the device's firmware, then install the V3 software as the V3 software doesn't recognise the device with earlier firmware. https://community.infineon.com/t5/USB-EZ-PD-Type-C/CY4500-failed-to-detect-device-for-upgrade-firmware/td-p/332299

[Fungus]

I didn't take any current measurements, but I did measure the claimed voltage domains, and all were supported when I selected each one with the PD trigger.

Looks like it's a good phone charger, too!

[Mechatrommer]

Here's my LiteOn, together with a capture of the capabilities, captured with a Cypress CY4500 protocol analyser (hooked up to a PD trigger board) and corresponding scope traces. These were taken at PD trigger insertion.

looks complicated than i thought. i was only interested to see how to make my own battery powered PSU. btw, this forum is fucked up... when i click the first image's thumbnail, different picture popped out, this happen frequently now... see attached.. even when i make a post with attachments, every time the first picture i uploaded in the list will become the last in my post, i have to shuffle the order to get correct view, really fucked up...  now i'm not sure if you people can see my attachments the way i see them from here.

[Howardlong]

Here's my LiteOn, together with a capture of the capabilities, captured with a Cypress CY4500 protocol analyser (hooked up to a PD trigger board) and corresponding scope traces. These were taken at PD trigger insertion.

looks complicated than i thought. i was only interested to see how to make my own battery powered PSU. btw, this forum is fucked up... when i click the first image's thumbnail, different picture popped out, this happen frequently now... see attached.. even when i make a post with attachments, every time the first picture i uploaded in the list will become the last in my post, i have to shuffle the order to get correct view, really fucked up...  now i'm not sure if you people can see my attachments the way i see them from here.

Yes, weird stuff happens when I try to edit a message and amend image attachments. It gets confused.

Here are the images again.

[Mechatrommer]

Here are the images again.

now it worked thanks.. i thought you dismantled your PSU like i did, but you have a dedicated PD tester. the USB3 pins are too deep and tiny inside for my DMM probe to reach. so i have to cut open the enclosure. now its taped back again no worry.

[ptluis]

Here are the images again.

now it worked thanks.. i thought you dismantled your PSU like i did, but you have a dedicated PD tester. the USB3 pins are too deep and tiny inside for my DMM probe to reach. so i have to cut open the enclosure. now its taped back again no worry.

So, from what I saw on your previous photo, the oscilloscope power on and operates fine if I only connect +12V (red) and GND (black) ignoring the blue wire (Vbus) right? This will make building a battery very simple.

[Mechatrommer]

Here are the images again.

now it worked thanks.. i thought you dismantled your PSU like i did, but you have a dedicated PD tester. the USB3 pins are too deep and tiny inside for my DMM probe to reach. so i have to cut open the enclosure. now its taped back again no worry.

So, from what I saw on your previous photo, the oscilloscope power on and operates fine if I only connect +12V (red) and GND (black) ignoring the blue wire (Vbus) right? This will make building a battery very simple.

yes its that simple. i tried it with DC (black red wires) to USB3 connector, i just dont know long term consequences... but it should be similar concept as 1st batch DHO800 which came with crappy 2 wires adapter found in OP. otoh my tear down only proved (and Howardlong's probing) the LiteOn adapter is probably USB3 PD 3 wires compliant PSU..

[Fungus]

I tried charging a phone with the new adapter and it worked really well (did a "fast charge")

[hbozyq]

I didn't take any current measurements, but I did measure the claimed voltage domains, and all were supported when I selected each one with the PD trigger.

So it's a legal universal PD charger? It's said it should not used for smart phone somewhere I have forgoten, maybe in the manual.

[ebastler]

So it's a legal universal PD charger? It's said it should not used for smart phone somewhere I have forgoten, maybe in the manual.

Yes, it is a regular universal charger. Rigol originally planned to include a cheap fixed 12V charger and shipped the first (beta?) units with those. But they changed that last-minute, without updating the manual yet.

The fixed 12V charger can be recognized by its special plug, with a little pin that stops you from inserting it into 3rd party devices. The DHO800/900 has a little hole next to its charging jack which matches with that pin.

[Fungus]

The fixed 12V charger can be recognized by its special plug, with a little pin that stops you from inserting it into 3rd party devices. The DHO800/900 has a little hole next to its charging jack which matches with that pin.

Oh, I hadn't noticed that.  They're not complete lunatics then. 

[Mechatrommer]

- touchscreen (a personal preference, fiddly in some environments)
- separate grounding/PE wire (asks for trouble)

Disable button on the front panel. Everything can be done without the touch screen.

how to change trigger mode (auto, normal, single.. esp normal) without touch screen? i dont find a button or rotary knob to change that, must use touch screen on trigger window..

[Fungus]

- touchscreen (a personal preference, fiddly in some environments)
- separate grounding/PE wire (asks for trouble)

Disable button on the front panel. Everything can be done without the touch screen.

how to change trigger mode (auto, normal, single.. esp normal) without touch screen? i dont find a button or rotary knob to change that, must use touch screen on trigger window..

There's a lot of things that need the screen.

[Andromedoh]

When I get mine I will do a teardown and schematic for the PSU make sure it's built right and help people fault finding in the future.

[ebastler]

When I get mine I will do a teardown and schematic for the PSU make sure it's built right and help people fault finding in the future.

Thanks! Rigol are, however, already using two different PSU brands (LiteOn and Lenovo), in addition to the cheap 12V supplies which were used for the pilot units only. And I would not be too surprised if they are already looking for a new, cost-reduced but good-enough option, since the price of the LiteOn and Lenovo units is probably hurting them.

Tearing down those switched-mode supplies also tends to be a warranty-voiding exercise since you need to crack the case open...

[Martin72]

You have made me curious...
You don't necessarily have to open it to find out what the quality is like.
Because in the end it's what comes out that matters....
I'm just thinking about a USB-C adapter on which you can make measurements.

[metrologist]

Or look for ripple when running scope on a battery.

[Mechatrommer]

When I get mine I will do a teardown and schematic for the PSU make sure it's built right and help people fault finding in the future.

good luck with that.. the aluminium heatsink enclosing it is full of glue from inside. i was not intending to go further since a simple 12-15VDC using $2 2-wires USB3 will do just fine in case the bundled PSU fails... a properly designed USB3 PD compliant is only usefull if you want to charge smartphone with it, imho.

[asmi]

When I get mine I will do a teardown and schematic for the PSU make sure it's built right and help people fault finding in the future.

What's the point of it, if they are using an off-she-shelf PSU? They can always switch to the new supplier, equally if user doesn't like it, he can easily use whatever USB-C PSU he likes, of which there are thousands on a market. PSU is one thing I don't really care about in this scope due to it being so easily replaceable.