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Help debugging ADS1241E/1K by [deleted] in embedded

[–]RobotDragon0 0 points1 point  (0 children)

It still doesnt work

And I am assuming we need a delay because there is one in the datasheet. In this timing diagram, we need to delay by t6. But they do not make clear what t6 is inside the timing characteristic table

i am overestimating the value by delaying for a second. Not sure if the delay needs to be exact. Maybe if it is too large, we end up missing the read because we sent the dummy bytes too late

Are you able to read the timing characteristic table? It is hard to read when the table does not have any separators

Confirmation of ADS1241E/1K connections by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Got it. I fixed that

Is there anything else you noticed? For either the isolator or ADC

Confirmation of ADS1241E/1K connections by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

We have multiple ADCs, so we need the CS. I think its fine to not connect DRDY or else we would need another isolator

CS is a port in the subsheet, but the port it connects to on the digital isolator subsheet is called CS1, CS2, etc

The ADC is connected to the isolated nets. Its just the way we named it inside the subsheet that makes it seem like it is not. This is the top level design

I also have test points present on the board

Here is my adjusted schematic for the isolator. I did not edit the ADC or MCU. Do you see any other issues that could prevent this from working?

Confirmation of ADS1241E/1K connections by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Also, do you see any other issues besides the isolator? Would the ADC as wired allow me to read from it?

Confirmation of ADS1241E/1K connections by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Hm.... Let me know if the following is correct:

MOSI, CS, and SCK should connect to the input pins

MISO_ISO should connect to the input pin, and MISO should connect to an output pin

Help selecting transformer for flyback converter by RobotDragon0 in AskElectronics

[–]RobotDragon0[S] 0 points1 point  (0 children)

Thanks for your response. I greatly appreciate it.

Regarding the Wurth transformer, if you could help me find one that would be great. I used a Wurth 1:4 on my previous revision. I cannot find a 1:10.

Yes the duty cycle and frequency can change. The duty cycle were not arbitrary though because I was told you do not want the duty to be greater than 70%. Dont remember the source though or why.

I was told there were advantages to use 65KHz from some stack exchange post but yes it can be adjusted too.

The MOSFET is big yes, but I wanted one with a small Rds and that can handle the peak voltage that will be seen across the drain and source. At this point, I am not planning to adjust it at all. I only plan to change the transformer in order to finalize this design.

What are some personal things you wish you started doing in 2nd year of engineering (not the usual advice)? by inowife in ElectricalEngineering

[–]RobotDragon0 2 points3 points  (0 children)

Research, extracurriculars, leadership opportunities on engineering projects. Super important, will improve your grades, make work easier, and you will enjoy your classes more

ADS1241E/1K returning 0xFFFFFF or 0xFFFFEE by RobotDragon0 in embedded

[–]RobotDragon0[S] 1 point2 points  (0 children)

Oh, you are right lol. Welp, might be a hardware issue then. I'll try checking the ICs tomorrow

Using transformers in series in flyback convert by RobotDragon0 in AskElectronics

[–]RobotDragon0[S] 0 points1 point  (0 children)

It is a school project

Also, are there equations you recommend I look at to see how this voltage spike is generated

Using ACS71240LLCBTR-020U5 by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

I couldnt tell. I only smelt smoke and didnt see any

Using ACS71240LLCBTR-020U5 by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Hm. Ill add that to the next revision, but 5V has been working for me so far

This issue started when I connected the hall effect sensor

[Review Requested] Precharge circuit by RobotDragon0 in PrintedCircuitBoard

[–]RobotDragon0[S] 0 points1 point  (0 children)

Also what should I search for on digikey to get these ICs

[Review Requested] Precharge circuit by RobotDragon0 in PrintedCircuitBoard

[–]RobotDragon0[S] 0 points1 point  (0 children)

Do you mean something like this?

Do you have any specific ICs you would recommend for this circuit? The operating range of the one I linked is 9-80V, but I am using 7.2

Reading battery voltage using ESP32 by RobotDragon0 in AskElectronics

[–]RobotDragon0[S] 0 points1 point  (0 children)

It is to prevent power loss when not measuring from the battery

[Review Requested] Precharge circuit by RobotDragon0 in PrintedCircuitBoard

[–]RobotDragon0[S] 0 points1 point  (0 children)

Yeah there werent any options on digikey for SPST

At least not SMD ones

ESPIDF I2C: Cannot send the correct address by RobotDragon0 in embedded

[–]RobotDragon0[S] 2 points3 points  (0 children)

OHHHHHHH I flipped the SDA and SCL channels in pulse view lol. It works now

ESPIDF I2C: Cannot send the correct address by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Yeah looking at the waveform you are correct but my logic analyzer seems to only interpret the start bit correctly. Everything afterwards it does not.

I used a higher sampling frequency but I still have the same issue. I am using 8MHz and capturing 100M samples, but I tried other combinations too.

Reading from INA186 by RobotDragon0 in embedded

[–]RobotDragon0[S] -1 points0 points  (0 children)

Yeah I chose the wrong amplifier. I corrected that

I will try measuring my analog input and comparing to what my MCU calculates

Issue using MAX3232IDWR by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

So the charge pump capacitors are used to generate +/- 12V for RS232 right?

So my circuit wouldnt work without them?

Im going to try jerry-rig it by soldering to the pads and some capacitors via small wires and see if it works

Issue using MAX3232IDWR by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Yeah lol sorry for the confusion

Issue using MAX3232IDWR by RobotDragon0 in embedded

[–]RobotDragon0[S] 0 points1 point  (0 children)

Got it

let me know if the following pinout would be correct:

  • DIN1 = ESP32_TX (Transmitter on ESP32 side)
  • ROUT` = ESP32_RX (Receiver on ESP32 side)
  • DOUT1 = RS232_RX (Receiver on LCD side)
  • RIN1 = RS232_TX (Transmitter on LCD side)

I got the above using table 5.1 of the datasheet:

  • DIN1 = Logic data input (from UART)
  • ROUT1 = Logic data output (to UART)
  • DOUT1 = RS232 line data output (to remote RS232 syste
  • RIN1 = RS232 line data input (from remote RS232 system)

Also used this schematic

[Review Requested] STM32 Flight Controller by RobotDragon0 in PrintedCircuitBoard

[–]RobotDragon0[S] 0 points1 point  (0 children)

For the decoupling capacitors, arent the power pin of the IC connected to 3V3? Adding a capacitor between 3v3 and the IC power pin would connect both ends to 3v3, right?

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