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Regarding application of TPS65381

alan zhu — Tue, 07 Feb 2017 07:24:04 GMT

Dear,

Regarding application of TPS65381, I have several questions and hope to get support from your side:

How to use NRES? Can it be connected directly to MCU? Is there pull-up resistor needed?
As we understand, DIAG_OUT is output of diagnostic signals selected by SPI, is it right? If choosing analog signal as output, how to select low-pass resistor and capacitor, what frequency need to filter out?
Is RSTEXT used to set delay time of NRES by adjusting resistance? How to select the resistor?
If we decide not to use CAN wake up function, how to configure CANWU pin (floating or pull down)?
If we choose 5V as sensor supply voltage, should VSIN be connected to VDD6? Should VTRACK be connected to VDD5? How to choose the resistor for VSOUT1 when we want unity gain feedback?
If we want VDD1 to be 1.2V, how to choose resistor for VDD1_SENCE? How to calculate it?

PGA450Q1EVM: GUI was frozen when opening

K.Yaita — Tue, 31 Jan 2017 02:59:35 GMT

Part Number: PGA450Q1EVM

Hi Team,

My customer got PGA450Q1EVM and I heard GUI was frozen when opening GUI.
I attached the picture after GUI was frozen.

His startup procedure is no ploblem according to the following E2E thread.
https://e2e.ti.com/support/applications/automotive/f/26/p/569058/2088597#2088597
1. Connect TI-GER board to EVM.
2. Connect and power EVM.
3. Connect USB from TI-GER to PC.
4. Open GUI.

He also tried the following startup procedure to isolate the TI-GER board, however same freeze error can be replicated..
1. Only connect the TI-GER board to the PC (EVM should not be connected or powered)
2. Open the GUI. Does the GUI still freeze?

What is concern?

Best Regards,
Yaita / Japan disty

RE: Regarding application of TPS65381

Scott Monroe — Tue, 07 Feb 2017 16:07:02 GMT

Hello Alan,

My answers below will be referencing Rev F of the TPS65381-Q1 datasheet: http://www.ti.com/lit/gpn/tps65381-q1

Additionally, there are other resources such as the design checklist and other application notes at: http://www.ti.com/product/TPS65381-Q1/technicaldocuments

Q1: How to use NRES? Can it be connected directly to MCU? Is there pull-up resistor needed?

A1: NRES is the reset output from the TPS65381. It is open drain with integrated pull up. The internal pull up is datasheet parameter 9.2, R_{NRES_ENDRV_PULLUP.}Whether an external one is needed depends on any other loading you may have in your system on the reset line.

Q2: As we understand, DIAG_OUT is output of diagnostic signals selected by SPI, is it right? If choosing analog signal as output, how to select low-pass resistor and capacitor, what frequency need to filter out?

A2: Any filtering requirements will be dependent on the MCU ADC. The MCU ADC should specify any filtering needed. The input resistance, and any filter resistance and capacitance will impact the settling time and the voltage level (resistor divider with between the TPS65381 output resistance and any filter or input resistance). The datasheet suggest the order to switch through the analog signals to minimize the settling time in section 5.4.1.9 Analog MUX (AMUX)

Q3: Is RSTEXT used to set delay time of NRES by adjusting resistance? How to select the resistor?

A3: Yes, RSTEXT is the pin by changing a resistance will adjust how long NRES is held low after an event that causes reset (or RESET state in TPS65381), reset extension time. Datasheet spec line 9.4, t_RSTEXT(22k_Ω₎ and spec line 9.4a, t_RSTEXT(0k_Ω_),give you two specified points for the reset extension time. This is described in section: 5.3.8 Reset Extension and shown in Figure 5-1. Power-Up and Power-Down Behavior.

Q4: If we decide not to use CAN wake up function, how to configure CANWU pin (floating or pull down)?

A4: CANWU pin is an input pin. One of two wake up pins, the other wake up pin is IGN. One of the two wake up pins need to be used to wake up the device. If one or the other wake up pins are not used they may be floated (there is an internal pull down) or an additional external pull down can be added.

Q5: If we choose 5V as sensor supply voltage, should VSIN be connected to VDD6? Should VTRACK be connected to VDD5? How to choose the resistor for VSOUT1 when we want unity gain feedback?

A5: With 5V sensor supply, VDD6 is likely the best choice since it will be more efficient to use the VDD6 pre-regulated supply into VSIN. For use of VSOUT1 configurations please see the application section of the datasheet where these are all documented. First you should decide if you want to track VDD5 or just have a 5V supply. I think the best application section to look at is: 6.2.2.3 VSOUT1 Tracking Linear Regulator, Configured to Track VDD5

Q6: If we want VDD1 to be 1.2V, how to choose resistor for VDD1_SENCE? How to calculate it?

A6: Please see application section: 6.2.2.2 VDD1 Linear Controller for how to calculate resistors for VDD1 and use VDD1.

Best Regards,

Scott

RE: PGA450Q1EVM: GUI was frozen when opening

Akeem Whitehead — Tue, 07 Feb 2017 11:03:11 GMT

Hi Yaita,

Also, ensure that the HEX jumper pins on the TI GER board are not shunt-shorted. Should appear as follows:

RE: PGA450Q1EVM: GUI was frozen when opening

K.Yaita — Mon, 06 Feb 2017 19:55:46 GMT

Hi Akeem-san,

I apologize for having overlooked.
I will try your procedure.

Best Regards,
Yaita

RE: PGA450Q1EVM: GUI was frozen when opening

Akeem Whitehead — Mon, 06 Feb 2017 19:37:59 GMT

Hi Yaita,

I attached the zip file containing the .EXE and .HEX to the bottom of my last message.

I also attached PGA450Q1GUI version 1.4 in the bottom of the last message.

Are you able to download both zip files?

RE: PGA450Q1EVM: GUI was frozen when opening

K.Yaita — Mon, 06 Feb 2017 19:22:07 GMT

Hi Akeem-san,

Thank you for your support.

>1. Open HIDBootLoader.exe.
Where can I get the HIDBootLoader.exe and *.HEX file?

Best Regards,
Yaita

RE: PGA450Q1EVM: GUI was frozen when opening

Akeem Whitehead — Mon, 06 Feb 2017 17:23:33 GMT

Hi Yaita,

Please try the following TI GER board reprogramming procedure:

The procedure for reprogramming firmware preloaded in the TI GER over USB allows updated firmware (*.HEX file) to be loaded into the microprocessor by executing the following procedure:

1. Open HIDBootLoader.exe.

2. With the TI GER connected to the USB bus, place a jumper in the “HEX” jumper location on the TI GER. The green LED will illuminate.

3. Depress the RESET pushbutton. Now the boot loader mode is activated.

4. In the HIDBootLoader program, verify that “Device attached” appears in status the window.

5. Click the “Open Hex File” button, and navigate to the location of the *.HEX file to be uploaded.

6. Once the file is selected, click on “Program/Verify”

7. Wait for programming conformation, then remove the HEX jumper and press RESET button.

Let me know if this procedure eliminates the GUI-freezing error. I am also attaching an older version of the GUI to determine if the error is due to a GUI update.

e2e.ti.com/.../Tiger-Firmware-update-kit.zip e2e.ti.com/.../PGA450-GUI-1.40.0.zip

TPS65311-Q1: TPS65311-Q1 Not working external FET

Jeho Shin — Wed, 18 Jan 2017 09:15:23 GMT

Part Number: TPS65311-Q1

It is configured as below, and when power is applied at the first, the gate voltage is not lowered and the FET does not operate.

That is VIN and GPFET are rising as the same voltage.

In such a case, what causes it?

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Krishnamurthy Hegde — Fri, 03 Feb 2017 02:57:25 GMT

Hi Jeho,

Thanks. I have already replied to that email and we will close this thread.

Regards,

Murthy

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Jeho Shin — Fri, 03 Feb 2017 02:17:44 GMT

Hi Murthy

Thank you for your great interest.

I sent some waveforms to your email address.
I would appreciate your review and advice.

Regards,

Jeho

RE: PGA450Q1EVM: GUI was frozen when opening

K.Yaita — Wed, 01 Feb 2017 18:20:47 GMT

Hi Scott-san,

I appreciate for your help.
I suspect it as the cause of defect of TI-GER board.. I also attempt to get another EVM in parallel.

Best Regards,
Yaita

RE: PGA450Q1EVM: GUI was frozen when opening

Scott Monroe — Wed, 01 Feb 2017 08:41:18 GMT

Hi Yaita-san,

I have assigned the appropriate engineer who should be responding to your question.

Thanks & Best Regards, Scott

RE: PGA450Q1EVM: GUI was frozen when opening

K.Yaita — Wed, 01 Feb 2017 05:59:40 GMT

Hi Joseph-san,
Thank you for moving to the Automotive Forum.

TI Automotive team,
Could you please give me comments about the issue?

Best Regards,
Yaita

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Krishnamurthy Hegde — Wed, 01 Feb 2017 01:44:47 GMT

Hi Jeho,

Were you able to solve this overshoot issue during the start up?

What was the root cause of this problem?

Regards,

Murthy

RE: PGA450Q1EVM: GUI was frozen when opening

Joseph Wu — Tue, 31 Jan 2017 00:28:03 GMT

Yaita-san,

I've moved this post to the Automotive Forum, where questions about the PGA450-Q1 have previously been posted. I'm sure that you'll find an answer here.

Joseph Wu

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Krishnamurthy Hegde — Mon, 30 Jan 2017 01:28:45 GMT

Hi Jeho,

Thanks for the details. It is difficult to debug remotely. However i can ask you to check the below. But not sure whether this works for you.

1. change BUCK2/3 output capacitors to 22uF. change Buck-1 output capacitor to 47uF and re check the compensation calculations for BUCK1.

2. Send me the exact schematics (complete PMIC page) in PDF format with all the changes you have made so far. Schematic you have sent is not complete. you can send it to my email ID (kmurthy.hegde@ti.com) and we keep it confidential.

3. fix the bottom sense resistor= 1.6k ohm and recalculate the top side sense resistors for BUCK2/3.

4. what have you done with COMP2/3?

5.short Vin and VINPROT (for testing purposes only). Also check with 12Vin

6. check PH/SW node of BUCK1/2 (zoom in to see few clock cycles clears during overshoot) during start up and send some pictures to me showing VINPROT, VBUCK1, VPH1, VPH2.

7. Add 500mA load (fixed resistor is ok) on each regulators and check the behavior.

8. check sense pins to see whether there is some noise coupling happening. If you have current probe, check the BUCK1 inrush current during start up.

9. if you have another board, modify the board according to the design checklist and try on another board. TPS65310A design checklist is also applicable to this device.

www.ti.com/.../slva609.pdf

Regards,

Murthy

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Jeho Shin — Sat, 28 Jan 2017 01:05:00 GMT

Hi Murthy

I always appreciate your answers.

I am a robot engineer, and we are developing our safety related controllers for certification.

I am very worried that my Project is too delayed because of this PMIC.

I know that designing the power section is not easy.

However, recent buck type regulators can get excellent voltage by adding fewer parts to the external.

Anyway, loads of the PMIC are only Safety CPU and Ethernet Controller In my system..

You can see that the output of each BUCK is slightly higher until VINPORT rises completely.

But the EV board is different.

I hope to get God's hand from you as soon as possible.

Regards,

Jeho

TPS43336-Q1: External clock frequency

tsuyoshi tokumoto — Thu, 19 Jan 2017 11:13:11 GMT

Part Number: TPS43336-Q1

Hi team,

Please let me ask you a question about TPS43336Q1.

When an external clock outside specification frequency range is input to the SYNC pin,
how does the TPS43336Q work?

   For example, the external clock frequency of 400 kHz is input to the Sync pin usually.
   If the external clock frequency change to 40kHz or4MHz,
   how will the TPS43336Q work?

Best regards.
Tsuyoshi Tokumoto

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Krishnamurthy Hegde — Thu, 26 Jan 2017 09:22:33 GMT

Hi Jeho,

Could you please provide the customer name and project details? I asked few times, but i didn't get the answer yet.

Regards,

Murthy

RE: TPS43336-Q1: External clock frequency

tsuyoshi tokumoto — Thu, 26 Jan 2017 05:34:20 GMT

Frank_san,

I apologize for the delay in my response.

Thank you very much for your prompt reply and detailed explanations.

I am always helped by your advice!

Best regards.
Tsuyoshi Tokumoto

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Jeho Shin — Wed, 25 Jan 2017 19:53:46 GMT

HI, Murthy

Thank you for your continued support.

As I modified it according to your recommendation, the required voltages are coming out normally.

However, the problem that the initial voltage of BUCK1, BUCK2, BUCK3 is slightly higher is not solved. I attach the investigation (waveform) related to the problem below.

We added 94uF to the outputs of each BUCK1, BUCK2, and BUCK3.

The waveform without FB8 beed is the same. EVB : Evaluation board.

< VINPORT-GPFET >

< VINPORT-BUCK1 >

<VINPORT-BUCK2>

< EVB-VIN-GPFET >

< EVB VIN-BUCK1 >

Regards,

Jeho

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Krishnamurthy Hegde — Wed, 25 Jan 2017 06:20:29 GMT

Hi Jeho,

Could you please let me know more details about the customer and project? You can email me if you are not confident to share this information on E2E.

Unless I have the detailed schematics, I cannot really tell why this happening. So far, no customer has complained about this behavior and i have not seen this behavior myself. Please try to bring your schematic close to EVM schematics and see whether this issue gets solved. Also it is very difficult to do such remote debug.

so suggestions to try:
* I noticed that you have only 4.7uF output capacitors and if this is really true, it may be too small. Please keep them at least around 20uF.
* send some zoomed in pictures of start up behavior showing, VIN, VINPROT, VBUCK1, VBUCK2
* You can try to apply some small load on the regulator (some 20-50ohm or so on BUCK1 ) and try
* You can try to decouple this regulator from other loads by removing FB8 component on 5V.. just to see whether something from load side is causing this issue.

Regards,

Murthy

RE: TPS65311-Q1: TPS65311-Q1 Not working external FET

Jeho Shin — Tue, 24 Jan 2017 19:52:10 GMT

Hi Murthy

Thanks to your help, the external FET problem has been solved.

There are, however, other problems continue to come out.

1) As shown in the figure below, the desired voltage stabilizes after about 30ms.

Not only 5V, but also 3.3V and 1.2V stabilize after about 30ms.

Commonly, during the initial 30ms, each output voltage is 1V higher than the desired output voltage, and then returns to the normal voltage.

The EV board does not show this phenomenon. How do I resolve it in my board?

Regards,

Jeho.

PGA450-Q1: PGA450 datasheet interpretation

Chris Seto — Tue, 17 Jan 2017 19:10:56 GMT

Part Number: PGA450-Q1

Support Path: /Product/Development and troubleshooting/

I'm having an issue with the PGA450 involving SPI communication.

My test setup:

SPI master: STM32F2

SPI phase: 2 edge

SPI polarity: 0

SPI wordsize: 8bit

The PGA450 eval board is connected the STM3 through a level shifter, to go from 3V3 TTL to 5V logic for the PGA450.

I'm trying to program registers within the ESFR. The first thing I do after PGA450 powerup is send a 0x16 0x2F 0x01 to put the onboard mcu into reset to allow for ESFR access. After another transfer, I get the following response to this command: 0x02 0x00 0x00. this would indicate that the command was successful.

Next, I try to read the current value of ESFR address 0xc0, as per the datasheet example. I send: 0x19 0xc0 0x00. Again, after another transfer, the response to this command is 0xc2 0x00 0x00. This would indicate a parity error.

What's going on here? As per datasheet example (Table 17) this is a valid command. Any ideas?

Chris