TPS2HB16-Q1: TPS2HB16A-Q1 Overcurrent Issue

Xiaoxiang Liu

Part Number: TPS2HB16-Q1

Tool/software:

Hi team,

Use the electronic load CC mode to replace the capacitive load.

When the set current is not greater than the switch current limit, the phenomenon does not reoccur, and the current outputs stably.

When the set current is greater than the switch current limit, the phenomenon reappears, and the current of tps2hb16a-q1oscillates.

How can this problem be avoided?

11 months ago

0 Timothy Logan 11 months ago

TI__Mastermind 36135 points

Xiaoxiang,

The problem here is the eLoad. Constant current mode introduces weird transients to the system that will cause the current limit to act unreliably.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1021866/faq-why-does-my-e-load-cause-my-high-side-switch-to-shut-down

For best results use an actual power resistor, or at least use the eLoad in constant resistance mode. Note that the current limit for high-side switches are meant to be used for overload conditions such as short-to-ground or capacitive inrush where VDS > 2.5V.

Best Regards,
Tim

0 Xiaoxiang Liu 11 months ago in reply to Timothy Logan

TI__Expert 7875 points

Hi Timothy,

Thanks for your support.

If the customer wants to verify the overcurrent protection function and settings, what method do you suggest?

Thanks

Xiaoxiang

0 Xiaoxiang Liu 11 months ago in reply to Xiaoxiang Liu

TI__Expert 7875 points

Hi Timothy,

The customer believes that there will be a negative current overshoot after triggering protection, and needs help to confirm the impact of this overshoot on the normal operation and service life of the High side switch.

Thanks

Xiaoxiang

0 Xiaoxiang Liu 11 months ago in reply to Xiaoxiang Liu

TI__Expert 7875 points

Hi team,

Could I get the reply today?

Thanks

Xiaoxiang

0 Timothy Logan 11 months ago in reply to Xiaoxiang Liu

TI__Mastermind 36135 points

Xiaoxiang,

Apologies for the delay- it is the holiday week in USA so replies will be delayed.

We would recommend just using an actual load- not an electronic load. In all of our testing we would just use an actual power resistor and discrete inductor. This will provide real world loading conditions and would best represent the behavior that they would see in their application.

Best Regards,
Tim

0 Xiaoxiang Liu 11 months ago in reply to Timothy Logan

TI__Expert 7875 points

The load has been identified. The customer wants to know if there will be any damage to the chip due to the reverse current of 7A caused by an external capacitor at the output. What is the maximum reverse voltage and reverse current that the output pins of the HB16-Q1 can withstand?

Thanks

Xiaoxiang

0 Timothy Logan 11 months ago in reply to Xiaoxiang Liu

TI__Mastermind 36135 points

Xiaoxiang,

Are you talking about a reverse polarity event where VS=0V and GND = 12V? In this case, the device would detect a reverse polarity event and turn on the main FET to dissipate all of the energy over the on-resistance of the FET and not the body diode.

If you are talking about forcing VOUT to a higher potential than VS outside a reverse polarity event and forcing current through the body diode- we do not specify this and would not have a way of even estimating it. The body diode is considered a parasitic path and there is no way to reliably rate it for current. If this is a legitimate use case for the application, it is recommended to use a diode or ideal diode on the VS line to block reverse current.

Best Regards,
Tim

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TPS2HB16-Q1: TPS2HB16A-Q1 Overcurrent Issue