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TPS3820: TPS3820 WDI Not Recognized Despite Compliant Signal, Batch Constant System Reset

RuiPing Wu — Wed, 17 Jun 2026 01:19:56 GMT

Part Number: TPS3820

TPS3820-50QPDBVRQ Lot Failure: WDI Feed Signal Meets Datasheet Specs But Watchdog Fails to Detect, Constant Reset Blocks System Boot; ABA Swap Test Confirms Failure Follows IC
Part Number: TPS3820-50QPDBVRQ1 (5V voltage supervisor, automotive grade)
Supply Voltage: +5V
Failure Phenomenon & Mass Production Data

1. End customer test failure: The board keeps asserting reset signal after power-up, system cannot boot up.

2. Root cause localized to watchdog circuit: The internal watchdog fails to recognize WDI feed pulses, watchdog timeout triggers permanent reset.

3. Oscilloscope measurement: WDI signal voltage level, pulse width and feed interval fully comply with all electrical specifications listed in TPS3820 datasheet.

4. Mass failure statistic: 19 defective units out of total 40 tested finished boards, failure rate = 47.5%.

5. ABA swap test conclusion:

◦ Replace faulty TPS3820 IC with new good unit → board works normally.

◦ Solder the failed IC onto a known-good reference board → constant watchdog reset failure reproduced.

◦ The defect source is confirmed to be the TPS3820 IC itself; PCB layout, MCU firmware and peripheral passive components are eliminated as root causes.

RE: TPS3820: TPS3820 WDI Not Recognized Despite Compliant Signal, Batch Constant System Reset

RuiPing Wu — Thu, 09 Jul 2026 05:31:00 GMT

Hello, this is the model: TPS3820-50QPDBVRQ1. We have replaced the faulty chips for the previous order. The new batch order is expected to be completed on July 10th. We will confirm it at that time. If you have any questions, I will contact you promptly. Thank you

RE: TXS02612: Support for SD card High-Speed Mode

Jack Guan — Thu, 09 Jul 2026 04:58:30 GMT

Hi Maeda-san,

Let me follow up tomorrow.

Regards,

Jack

TXS02612: Support for SD card High-Speed Mode

Daisuke Maeda — Tue, 07 Jul 2026 10:16:46 GMT

Part Number: TXS02612

Does TXS02612 support SD card High-Speed Mode?

When VCCA = 3.3 V and VCCB = 3.3 V:
The propagation delay (tPD) of clock from controller to SD card (CLKA to CLKB) is 3.5 ns (max).
The propagation delay (tPD) of data from SD card to controller (DATB to DATA) is 3 ns (max).

For SD Card High-Speed Mode:
The Output Delay Time during Data Transfer Mode (tODLY) is 14 ns (max).

The total of these delays is 20.5 ns, which exceeds the 20 ns clock period of High-Speed Mode (50 MHz).

The TXS02612 is unlikely to support SD card High-Speed Mode.

Best regards,

Daisuke

SN74AUC74: Soldering Problem

Alexander Matias — Thu, 09 Jul 2026 01:06:22 GMT

Part Number: SN74AUC74

Hi everyone,

Regarding SN74AUC74, we encounter an issue during the assembly of this part wherein the pins of this part are not fully soldered (solder fillet is not fully formed on sides). In this regard, I would like to confirm if it is acceptable for this part to have this kind of soldering conditions without affecting its specification (as long as it is fully connected underneath).

Thanks

RE: SN74AUC74: Soldering Problem

Isla Crommelin — Thu, 09 Jul 2026 02:58:52 GMT

This soldering issue sounds tricky, Alexander! On another note, I've been unwinding lately with a puzzle game called block blast . There's something so satisfying about clearing rows and keeping the board from filling up – a different kind of precision. Have you found similar "acceptable" tolerances in any other component assembly, even if it's not ideal?

CD4060B: Sim Model

Michael Balourdas — Wed, 08 Jul 2026 22:22:25 GMT

Part Number: CD4060B

Hello,

Is there any simulation model for this device?

Thanks,

Michael

CD74AC14: CD74AC14M96 updates in datasheet (June 2026)

Erika Alejandre — Thu, 02 Jul 2026 21:35:19 GMT

Part Number: CD74AC14

Hi, I hope you are well. :)

I would like to know what are the correct values that changed from CD74AC14M96 Datasheet (August 2024) to CD74AC14M96 Datasheet (June 2026), because in the picture that I added below (omit yellow part) the values that I circuled in blue are not align with the updates that we have in both datasheets.

RE: CD74AC14: CD74AC14M96 updates in datasheet (June 2026)

Nikki Dengel — Wed, 08 Jul 2026 20:32:57 GMT

Hi Erika,

Please take a look at the online datasheet. It should be fully updated now so that everything matches the numbers found in the newest revision history.

Regards,

Nikki

SN74LVC2G126: Lead Time Extensions and Decomits

Daniel Nielsen — Wed, 08 Jul 2026 20:04:10 GMT

Part Number: SN74LVC2G126

Please confirm the lead time on this part. We are showing pushouts on our POs to over 52 weeks.

SN54AC14: IBIS Model Request

Brody Kisner — Wed, 08 Jul 2026 15:12:35 GMT

Part Number: SN54AC14

Hi,

I was looking to find an IBIS model for the 5962-87624012A, the LCCC 20 version of the SN54AC14. Any assistance would be appreciated.

Thanks

RE: SN54AC14: IBIS Model Request

Brody Kisner — Wed, 08 Jul 2026 19:54:38 GMT

Hi Ian, I came across this conversation about a similar subject asking for an IBIS model, but the link attached does not seem to contain an IBIS model that I could find. SN54AC14: IBIS model for SNJ54AC14W - Logic forum - Logic - TI E2E support forums Could you point me to where the IBIS model for this device is located since it does exist? Thank you

RE: SN54AC14: IBIS Model Request

Ian Graham — Wed, 08 Jul 2026 19:28:57 GMT

Hi Brody,

If an IBIS model is not available on TI.com, it has not been made.

Best,

Ian

RE: SN54SC245-SEP: How can I get a formal quote for this part

Michael Marinello — Wed, 08 Jul 2026 17:18:24 GMT

Alex Segler

SN54SC245-SEP: How can I get a formal quote for this part

David Crane — Wed, 08 Jul 2026 11:15:52 GMT

Part Number: SN54SC245-SEP

Can TI gernerate quotes for parts? My purchasing department is asking for a formal quote.

SN74LV8T245: Input voltage tolerance on IO pins

Alexis Monaci — Thu, 25 Jun 2026 08:26:47 GMT

Part Number: SN74LV8T245

Hello dear TI team,

In my application, I am using the SN74LV8T245 to interface a 3V3 FPGA to a 5V bus. I used this IC because it is bidirectionnal and available in VQFN small package.

By default at power on the OE pin is high (chip disabled). On a buffer I saw a failure on a IO and after digging into the datasheet the specifications are confusing me:

The ouput in the high impedance state is absolute maximum 4,6V (no information on recommended operating conditions) and the inputs are specified with 5,5V in recommended operating conditions.
the Ax and Bx pins are bidirectionnal so connected to input and output internal buffer

So when the chip is disabled the Ax and Bx support max 4,6V but when enabled and configured in inputs the Ax and Bx support 5,5V?

If this is the case I assume that there is a kind of internal switch in series with the output buffer to disconnect it and disconnect the output clamping diodes. Can you confirm this?

In datasheet like SN74LVC8T245 the informations in specification tables are very clear on that points.

Thank you in advance!

RE: SN74LV8T245: Input voltage tolerance on IO pins

Joshua Salinas — Wed, 08 Jul 2026 16:30:34 GMT

Hello Alexis,

Either SN74LV245A or SN74LXC8T245 should work in this case. Both can support higher than 6.5V in a Hi-Z state.

Regards,

Josh

RE: SN54SC245-SEP: How can I get a formal quote for this part

David Crane — Wed, 08 Jul 2026 16:21:11 GMT

Is it Patrick Townsend or Alex Segler?

RE: SN74LV1T34: VCC=open, Input=3.3V

Joshua Salinas — Wed, 08 Jul 2026 16:13:31 GMT

Hello Ishiwata-san,

Yes I can verify this. Please allow until the end of the week to provide results.

Regards,

Josh

SN74LV1T34: VCC=open, Input=3.3V

Shuji Ishiwata — Mon, 29 Jun 2026 02:41:43 GMT

Part Number: SN74LV1T34

Hi All,

I have a question about SN74LV1T34.

When the VCC pin is left open and a 3.3V signal is applied to the input, the input voltage back-feeds into the VCC pin, resulting in a voltage of approximately 3.0V.
To prevent this back-flow to the VCC pin, a 47kohm series resistor is placed on the input line.

Is there any issue with installing a 47kohm series resistor on the input?

Best Regards,
Ishiwata

RE: SN74LV8T245: Input voltage tolerance on IO pins

Alexis Monaci — Wed, 08 Jul 2026 16:06:44 GMT

Hello Joshua, I re open the ticket because we performed some tests on the IC.

With an unpowered board composed of a FPGA on a 3V3 rail and several SN74LV8T245 on 3V3 as well with pullup resistors on OE/DIR pins, we applied a voltage through a 1kohm resistor on a Bx IO:

with 3V3 applied: 2.1V on Bx pin and 1.5V on 3V3 rail
with 5V applied: 2.4V on Bx pin and 1.7V on 3V3 rail
with 7V applied: 2.6V on Bx pin and 1.8V on 3V3 rail

During tests in our application the IC allows current injection from 5V rail trhough pullup resistors and the 3V3 voltage rises up to 4.3V that is over the maximum rating of our FPGA.

I guess that the clamping diodes are allways present on IO pins (whether or not there is voltage applied on Vcc or OE pin level), and that this IC is not 5V tolerant on IO pins. Can you confirm this?

Also we are looking for a pin to pin replacement with the SN74LV245A. From its specification it is clearly 5V tolerant on its IOs, can you confirm this.

Thank you in advance!

RE: SN54SC245-SEP: How can I get a formal quote for this part

Michael Marinello — Wed, 08 Jul 2026 15:33:11 GMT

Hi David,

I've reached out to our TI sales representative on this topic. They will reach out to you to get the formal quote process going.

Best,

Michael

RE: SN74LVC1G14: Schmitt trigger Inverter SN74LVC1G14

Ian Graham — Wed, 08 Jul 2026 15:02:41 GMT

Hi Pascal,

Nothing is attached.

SN74LVC1G14: Schmitt trigger Inverter SN74LVC1G14

Pascal Schneider — Wed, 08 Jul 2026 08:00:25 GMT

Part Number: SN74LVC1G14

We have been looking for a second source for the Schmitt trigger inverter from NXP (74LVC1G14GW) and identified a potential alternative from TI (SN74LVC1G14).

However, in our circuit (see attached image), we observe that the TI inverter draws significantly higher current compared to the NXP device approximately 2 mA.

Based on the datasheet, we are unable to explain this difference.

Could you please assist us in understanding this behavior?

Thank you for your support.

SN74LVC2G34: SN74LVC2G34DCKR Thermal Resistance Data

Claudia Dufour — Wed, 01 Jul 2026 19:21:23 GMT

Part Number: SN74LVC2G34

The SN74LVC2G34 datasheet includes the junction-to-ambient thermal resistance for the DCK package. Are there additional thermal properties available for this package? (thetaJC, thetaJB, psiJB, psiJT, etc.)