DRV8848: output current accuracy (ΔItrip)

Yuta Nishie

Genius 3370 points

Part Number: DRV8848
Other Parts Discussed in Thread: DRV8426E, DRV8424, DRV8428

Hi,

Our customer is considering using the following products:

・DRV8848

・DRV8426E

・DRV8424

・DRV8428

And customer want information on what percentage of the output current error will be under the following conditions:

・ Input voltage range: 10.3V to 13.1V
・ Set current value: 300mA
・ Specifications Environmental temperature: -15 ℃ ～ 55 ℃

■Is it possible to provide the data of output current error (ΔItrip)?

Best Regards,

Nishie

over 2 years ago

+1 Jacob Thompson over 2 years ago

TI__Mastermind 22200 points

Hello Nishie-san,

Here is the current trip accuracy for DRV8426E, DRV8424, and DRV8428:

Parameter		Min	Max
ΔI_TRIP(Current trip accuracy)	I_O = 1.5 A, 10% to 20% current setting	–15%	15%
ΔI_TRIP(Current trip accuracy)	I_O = 1.5 A, 20% to 67% current setting	–10%	10%
ΔI_TRIP(Current trip accuracy)	I_O = 1.5 A, 68% to 100% current setting	–5%	5%

I'm having trouble finding this information for the DRV8848. Here's a forum post discussing the DRV8848 ΔI_TRIP: https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/717944/drv8848-vref-current-control-accuracy

I am going to ask my team about the DRV8848 and will post a reply if I learn more information. Let me know if this answers your question, thanks!

Regards,

Jacob

0 Ryan Kehr over 2 years ago in reply to Jacob Thompson

TI__Guru 54795 points

Hello,

The DRV8848 has external current sense resistors while the rest of the devices above are integrated...no need for external sense resistors. I would prefer to promote the other devices for new designs with the advantage of integrated sensing.

Regards,

Ryan

0 Yuta Nishie over 2 years ago in reply to Jacob Thompson

Genius 3370 points

Hi Thompson-san,

Thank you for your reply.

I think that the ΔI trip of DRV8426E, DRV8424, and DRV8428 is the data at @ 25 ℃.
Customers also need data when the temperature range changes from -15 ° C to 55 ° C.
Is there any data when the temperature is changed?

Best Regards,

Nishie

0 Yuta Nishie over 2 years ago in reply to Ryan Kehr

Genius 3370 points

Hi Ryan-san,

Thank you for your reply.

I understand that the DRV8848 has an external sense resistor, which makes the output current accuracy worse than other devices.
Is this correct?
Also I would like to offer customers a device other than the DRV8848.

Best Regards,

Nishie

0 Jacob Thompson over 2 years ago in reply to Yuta Nishie

TI__Mastermind 22200 points

Hello Nishie-san,

Unfortunately I don't think we have the ΔI_TRIPdata for different temperatures. Sorry!

Regards,

Jacob

+1 Ryan Kehr over 2 years ago in reply to Jacob Thompson

TI__Guru 54795 points

Nishie-san,

The table above is in the datasheet for DRV8426E and it is over operating free-air temp. Please look at the top of the table in the datasheet. So, this is over -40C-125C. Please check the other datasheets for this information as it is different.

Regards,

Ryan

0 Yuta Nishie over 2 years ago in reply to Ryan Kehr

Genius 3370 points

Hi Jacob-san,

Ryan-san,

Thank you for teaching me
I will check the data sheet based on what you have told me.

Best Regards,

Nishie

0 Yuta Nishie over 2 years ago in reply to Yuta Nishie

Genius 3370 points

Hi Jacob-san,

Ryan-san,

sorry.
Let me ask you an additional question.
Should I refer to the above table for ΔItrip when VM = 10.3V ~ 13.1V?

Best Regards,

Nishie

+1 Jacob Thompson over 2 years ago in reply to Yuta Nishie

TI__Mastermind 22200 points

Hey Nishie-san,

10.3V - 13.1V is within the recommended operating conditions for VM, so yes the table should still be a good reference. We don't have any other tables for ΔItrip in different temperature or voltage ranges so that table is the best and only reference for this scenario.

Regards,

Jacob

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DRV8848: output current accuracy (ΔItrip)