Quite often the question arises what oscilloscope bandwidth is required to probe a certain bus or serial interface, so in a moment of boredom I assembled the following table from various sources.
Please keep in mind that this list shows the bandwidth required to examine the signal integrity. Decoding often works with less bandwidth, although it may be unreliable/erroneous as with insufficient bandwidth the waveform on the screen hasn't much in common with how the real signal looks like.
| Standard | | Bit Rate | | Minimum Bandwidth req'd |
| Ethernet 100BT | | 125Mbps | | 500MHz |
| Ethernet | | 250Mbps | | 1GHz |
| Fibre Channel 50MB/s | | 531.25Mbps | | 1.5GHz |
| USB2 Super-Speed | | 480Mbps | | 2GHz |
| IEEE1394b Firewire 800 | | 786.43Mbps | | 2GHz |
| RapidIO LP-LVDS | | 1Gbps | | 2.5GHz |
| Fibre Channel 1GFC | | 1.0625Gbps | | 2.5GHz |
| DDR2-800 | | 800MTps | | 3.5GHz |
| Ethernet 1000BT | | 1.25Gbps | | 3.5GHz |
| IOF | | 1.24416Gbps | | 3.5GHz |
| RapidIO LP-LVDS | | 1.25Gbps | | 3.5GHz |
| RapidIO LP-LVDS | | 1.5Gbps | | 4GHz |
| SATA (SATA150) | | 1.5Gbps | | 4GHz |
| IEEE1394b Firewire 1600 | | 1.5729Gbps | | 4GHz |
| DVI | | 1.65Gbps | | 4GHz |
| HDMI 1.2a | | 1.65Gbps | | 4GHz |
| RapidIO LP-LVDS | | 2Gbps/2.5Gbps | | 6GHz |
| PCI Express 1.x | | 2.5Gbps | | 6GHz |
| DDR3-1600 | | 1.6GTps | | 8GHz |
| ExpressCard | | 2.5Gbps | | 8GHz |
| InfiniBand | | 2.5Gbps | | 8GHz |
| RapidIO LP-LVDS | | 3.125Gbps | | 8GHz |
| DisplayPort 1.1 | | 2.7Gbps | | 8GHz |
| HyperTransport 2.0 | | 2.8Gbps | | 8GHz |
| SAS 1.0/1.1 | | 3Gbps | | 8GHz |
| SGMII | | 3.125Gbps | | 8GHz |
| XAUI | | 3.125Gbps | | 8GHz |
| Firewire | | 3.2Gbps | | 8GHz |
| DDR4 | | 4GTps | | 10GHz |
| HDMI 1.3b | | 3.4Gbps | | 10GHz |
| SATA2 (SATA300) | | 3Gbps | | 10GHz |
| Fibre Channel 4GFC | | 4.25Gbps | | 13GHz |
| Serial RapidIO | | 4.25Gbps/5Gbps | | 13GHz |
| InfiniBand | | 5Gbps | | 13GHz |
| PCI Express Gen2 | | 5Gbps | | 13GHz |
| PCI Express Gen3 | | 8Gbps | | 13GHz |
| HyperTransport 3.0 | | 5.2Gbps | | 13GHz |
| USB 3.0 | | 5Gbps | | 13GHz |
| DisplayPort 1.2 | | 5.4Gbps | | 16GHz |
| GDDR5 | | 6Gbps | | 16GHz |
| SAS2 | | 6Gbps | | 16GHz |
| SATA3 (SATA600) | | 6Gbps | | 16GHz |
| Serial RapidIO | | 6.25Gbps | | 16GHz |
| HyperTransport 3.1 | | 6.4Gbps | | 16GHz |
| QPI | | 6.4Gbps | | 16GHz |
| 10GBT | | 10.3125Gbps | | 20GHz |
| SFI/SFP+ | | 10.3125Gbps | | 20GHz |
| CEI-11 | | 11Gbps | | 25GHz |
| SAS3 | | 12Gbps | | 25GHz |
| InfiniBand | | 25.78125Gbps | | 50GHz |
| CEI-25/28 | | 25Gbps/28Gbps | | 60GHz |
I'll try to update the table from time to time.
Thanks for the useful table - perhaps its worth pointing out that the bandwidth requirements for decoding serial data are different from making signal integrity measurements?
Take the 250Mbps Ethernet below - you can think of that as a 125MHz square wave signal in terms of frequency. 1GHz is a sensible bandwidth for signal integrity but 500MHz would be more than enough if you are more interested in decoding the data.
Thanks for the useful table - perhaps its worth pointing out that the bandwidth requirements for decoding serial data are different from making signal integrity measurements?
Thanks for bringing this up. I've updated the original post to reflect that.
That's kind of depressing from a hobby-budget-scope point of view
Perhaps a list of what you *can* do with a 100MHz or 300MHz scope would be more uplifting?
That's kind of depressing from a hobby-budget-scope point of view
Perhaps a list of what you *can* do with a 100MHz or 300MHz scope would be more uplifting?
<list>
1. A 56K modem...on a good day.
</list>
That's kind of depressing from a hobby-budget-scope point of view
Perhaps a list of what you *can* do with a 100MHz or 300MHz scope would be more uplifting?
Well, it would be a whole lot shorter
But yeah, low bandwidth scopes simply don't cut it for modern high speed busses. Which I know must be depressing, as people sometimes ask for a suitable entry level scope for doing USB or Ethernet stuff. Unfortunately that's not gonna happen, even USB2 is already lower high-end territory.
And then there's the question of probing...
I've successfully decoded PCIe Gen1 on my (bandwidth-hacked) Tek DPO5034, so don't panic
.
That's kind of depressing from a hobby-budget-scope point of view
Perhaps a list of what you *can* do with a 100MHz or 300MHz scope would be more uplifting?
SPI, I2C, RS232...
(Weirdly enough that's a list of the protocols that are in the menu of my 'scope)
I've successfully decoded PCIe Gen1 on my (bandwidth-hacked) Tek DPO5034.
Decode of PCIe 1.x can work with a 2GHz scope, but that's pretty much it.
It always stroke me as odd that Tek offered PCIe Serial Analysis on a scope series that doesn't even have sufficient bandwidth that's required for it (the DPO5k only goes to 2GHz).
That's kind of depressing from a hobby-budget-scope point of view
Perhaps a list of what you *can* do with a 100MHz or 300MHz scope would be more uplifting?
SPI, I2C, RS232...
(Weirdly enough that's a list of the protocols that are in the menu of my 'scope)
Our InfiniiVision scopes support I2C, SPI, UART (RS232,485, etc), CAN (-dbc), LIN, FlexRay (lol), I2S, MIL-STD1553, ARINC429, SENT
So there's quite a bit you can do with the lower bandwidth scopes. But once you start getting into high speed digital you're going to have to upgrade. The list from Wuerstchenhund is (AFAIK) more industry focused and less hobbyist focused.
Slide 49 on page 25 is a good reference for this, too.
http://www.keysight.com/upload/cmc_upload/All/Oscilloscope_BW_Reqmts_for_Emerging_Serial_Data_Intfcs.pdf
From an older but interesting talk on optimizing your bandwidth.
Thanks for the link, I've added DDR2 and DDR3 to the list.
Funny that it lists SAS 1.5Gbps, as this never was a real standard (SAS Generation 1 is 3Gbps).
The list from Wuerstchenhund is (AFAIK) more industry focused and less hobbyist focused.
Well, actually it
is aimed at hobbyists
These days quite often even hobbyists want to look at stuff like USB2/3, DDR2 and HDMI, and on occasion someone asks for a cheap entry level scope recommendation to do that. The list is meant to be as a guide to show that even measly USB 2.0 is pretty much out of reach of any entry-level (and mid-range) scope (and essentially anything that carries the Rigol logo).
Thanks heaps for creating this list!!!
Our InfiniiVision scopes support I2C, SPI, UART (RS232,485, etc), CAN (-dbc), LIN, FlexRay (lol), I2S, MIL-STD1553, ARINC429, SENT
And the Rohde and Schwarz RTM and RTA oscilloscopes also support all of these decodes ... just saying ....
https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/Option_sheet_-_RTx-K1_-K2_-K3_-K5_-K6_-K7_serial_protocol_triggering_and_decoding_v1.10.pdf
So much has changed in just 6 years since this thread was last active where now even some relatively cheap scopes support I2C, SPI, UART, CAN, LIN (Standard) and CAN FD, FlexRay, I2S, MIL-STD-1553B, SENT, and Manchester.
Sales people picking a fight. -ding ding- round one
