Siglent SDS800X HD Review & Demonstration Thread

[Performa01]

Here is the second part, including the following main topics:

MSO
HAM Test
User Comments

Figures
Tables

[eTobey]

...

On page 23 you wrote: "At 5 μs/div, the SDS824X HD takes an average of 650 μs/frame and a maximum of <2 ms/frame." I dont get what these 650us/frame mean. I would think it would be a constant 50us as you can see on the screen?

[2N3055]

...

On page 23 you wrote: "At 5 μs/div, the SDS824X HD takes an average of 650 μs/frame and a maximum of <2 ms/frame." I dont get what these 650us/frame mean. I would think it would be a constant 50us as you can see on the screen?

At 5µs/div  50µs is interval shown on the screen.
To do that scope has to trigger, capture, process signal, display and all measurements, and reconfigure to get ready to get another trigger.
That is called retrigger time.
Retrigger time hence consist of time when actual capture is happening and so called "blind" time, while scope processes data and going back to Ready status.

So that sentence means that that when scope is in 5µs/div retrigger time is 650µs/MAX 2ms
Full table of retrigger times(triggers/s) is on pg. 24.

Make note that with same settings, in sequence mode retrigger time is 52us, meaning "blind time" is 2µs.

That is why it is recommended to use sequence mode if you need to capture fast bursts of signal.

[BRZ.tech]

Hi,
Dear @Performa01
I return with the “Newbie” questions.
I am studying how to measure the Slew Rate of an Operational Amplifier in a DSO/MSO.
In this case, I thought this video from Texas Instruments was really good:
https://www.ti.com/video/4078676441001#:~:text=Slew%20rate%20is%20defined%20as,of%20the%20output%20signal's%20amplitude

In order not to waste time, TI defined what the Slew Rate is (time 0min:28sec), and that the “Unit” of measurement is (V/us), photo attached.
TI presented the Slew Rate of different Operational Amplifiers (time 04min:05sec), photo attached.

In the SDS800X HD datasheet, on page 16, in “Horizontal Paramenters” and “Miscellaneous Parameters”, it does not state that it automatically measures Slew Rate.
But it states in “Miscellaneous Parameters” that it automatically measures Positive Slope and Negative Slope.
In the SDS800X HD datasheet, on page 17, it states in “Power Analysis” (optional): “Measure”, which automatically measures the Slew Rate.

In the SDS800X HD datasheet, on page 06, “Parameter Statistics Function”, photo attached, that shows the measurement of a Square Wave Signal of Amplitude = 5Vpp, and f = 10MHz.
In the “PSlope(C1)” column, it presents the “average value”, with: (Mean = 1.0282K V/us), which is extremely fast for an Operational Amplifier, considering data from the best TI OA, according to the attached table.

“Newbie” Questions:
1. Carry out a test with the SDS800X HD, with Square Wave excitation, with Amplitude = 5Vpp and f = 10MHz, repeating the test of: “Parameter Statistics Function”.
Perform the measurement in “Unit”: (V/us), “Slew Rate” and “Positive Slope”.
If there are, explain what are the differences between the “Slew Rate” and “Positive Slope” measurements?

2. Regarding the “Slew Rate” and “Positive Slope” measurements, the performance measurement of the Operational Amplifier, is or is not, the same thing as performing the “Power Analysis” (optional) of the SMPS, for the automatic measurement of Slew Rate?
If they are different, I suggest SIGLENT add the Slew Rate measurement to the SDS800X HD menu, “Horizontal Parameters”.

Anyone on the topic can comment on my questions.
Translation with Google Translate.
Grateful for the attention.

[2N3055]

Hi,
Dear @Performa01
I return with the “Newbie” questions.
I am studying how to measure the Slew Rate of an Operational Amplifier in a DSO/MSO.
In this case, I thought this video from Texas Instruments was really good:
https://www.ti.com/video/4078676441001#:~:text=Slew%20rate%20is%20defined%20as,of%20the%20output%20signal's%20amplitude

In order not to waste time, TI defined what the Slew Rate is (time 0min:28sec), and that the “Unit” of measurement is (V/us), photo attached.
TI presented the Slew Rate of different Operational Amplifiers (time 04min:05sec), photo attached.

In the SDS800X HD datasheet, on page 16, in “Horizontal Paramenters” and “Miscellaneous Parameters”, it does not state that it automatically measures Slew Rate.
But it states in “Miscellaneous Parameters” that it automatically measures Positive Slope and Negative Slope.
In the SDS800X HD datasheet, on page 17, it states in “Power Analysis” (optional): “Measure”, which automatically measures the Slew Rate.

In the SDS800X HD datasheet, on page 06, “Parameter Statistics Function”, photo attached, that shows the measurement of a Square Wave Signal of Amplitude = 5Vpp, and f = 10MHz.
In the “PSlope(C1)” column, it presents the “average value”, with: (Mean = 1.0282K V/us), which is extremely fast for an Operational Amplifier, considering data from the best TI OA, according to the attached table.

“Newbie” Questions:
1. Carry out a test with the SDS800X HD, with Square Wave excitation, with Amplitude = 5Vpp and f = 10MHz, repeating the test of: “Parameter Statistics Function”.
Perform the measurement in “Unit”: (V/us), “Slew Rate” and “Positive Slope”.
If there are, explain what are the differences between the “Slew Rate” and “Positive Slope” measurements?

2. Regarding the “Slew Rate” and “Positive Slope” measurements, the performance measurement of the Operational Amplifier, is or is not, the same thing as performing the “Power Analysis” (optional) of the SMPS, for the automatic measurement of Slew Rate?
If they are different, I suggest SIGLENT add the Slew Rate measurement to the SDS800X HD menu, “Horizontal Parameters”.

Anyone on the topic can comment on my questions.
Translation with Google Translate.
Grateful for the attention.

Short answer, yes, [Positive slope] is slew rate measurement of positive going signal and [Negative slope] is respectively is slew rate measurement of negative going signal.

[Performa01]

Slew Rate Measurement

In the SDS800X HD datasheet, on page 06, “Parameter Statistics Function”, photo attached, that shows the measurement of a Square Wave Signal of Amplitude = 5Vpp, and f = 10MHz.
In the “PSlope(C1)” column, it presents the “average value”, with: (Mean = 1.0282K V/us), which is extremely fast for an Operational Amplifier, considering data from the best TI OA, according to the attached table.

I’ve had a look at Texas Instruments and have found no less than 57 operational amplifiers capable of a Slew Rate of 2 kV/µs or faster. There are still 13 OpAmps with a Slew Rate faster than 5 kV/µs, the fastest being the THS3491, which manages 8000 V/µs.

In the light of this, 1000 V/µs would have required a fast hybrid amp in the Seventies of last century, but isn’t particularly fast for a monolithic integrated OpAmp today.

1. Carry out a test with the SDS800X HD, with Square Wave excitation, with Amplitude = 5Vpp and f = 10MHz, repeating the test of: “Parameter Statistics Function”.
Perform the measurement in “Unit”: (V/us), “Slew Rate” and “Positive Slope”.
If there are, explain what are the differences between the “Slew Rate” and “Positive Slope” measurements?

It needs not be complicated. Here’s a 10 ns wide pulse with 2 ns rise-time, which is at the edge of accurate measurements with an SDS824X HD:


SDS824X HD_Slew_Pulse_W10ns_RT2ns

As can be seen, the rise-and fall-times are accurately measured as ~2 ns. The slew rate should be 80% * 5 V / 0.002 µs = 4 V / 0.002 µs = 2 kV/µs. The actual measurement is off by some 2.76% for the positive slope.

It should be kept in mind that the universal definition of the thresholds to be at 10% and 90% might not be valid in every industry, hence these thresholds are user-definable – see the measurement config submenu displayed in the above screenshot.

2. Regarding the “Slew Rate” and “Positive Slope” measurements, the performance measurement of the Operational Amplifier, is or is not, the same thing as performing the “Power Analysis” (optional) of the SMPS, for the automatic measurement of Slew Rate?
If they are different, I suggest SIGLENT add the Slew Rate measurement to the SDS800X HD menu, “Horizontal Parameters”.

It is all the same thing – Slew Rate is Slew Rate, universally defined in volts per second, no matter what package uses this measurement. Positive and negative slope measurements just measure the Slew Rate on positive and negative transitions.

[pdenisowski]

“Newbie” Questions:
1. Carry out a test with the SDS800X HD, with Square Wave excitation, with Amplitude = 5Vpp and f = 10MHz, repeating the test of: “Parameter Statistics Function”.
Perform the measurement in “Unit”: (V/us), “Slew Rate” and “Positive Slope”.
If there are, explain what are the differences between the “Slew Rate” and “Positive Slope” measurements?

2. Regarding the “Slew Rate” and “Positive Slope” measurements, the performance measurement of the Operational Amplifier, is or is not, the same thing as performing the “Power Analysis” (optional) of the SMPS, for the automatic measurement of Slew Rate?

Anyone on the topic can comment on my questions.

I recently made a short (< 6 min) video on slew rate measurements using an oscilloscope (primarily in the context of switch mode power supplies).  It's the same measurement (delta_V/t) regardless of whether you're measuring an op amp or SMPS, although the way you acquire the voltage waveform may be different depending on the application.

Slew rate is often included in "power analysis" option packages, but in my experience, most people just measure it "by hand" and don't really require a special option to do it.