TLC5947: Electrostatic Discharge (ESD) Protection

Johnny Okeeffe

Part Number: TLC5947

Tool/software:

I'm looking for feedback on the recommended method to protect LEDs connected to the TLC5947. In my current configuration, we use TVS diodes on the 24V line feeding the LEDs, but still observe that the TLC5947 can be damaged by ESD pulse to LED areas of our system. Results include change in LED brightness on ESD hit and/or damage to TLC5947 on ESD hit.

For reference, LED_SUPPLY_A net is feeding the diodes with 24V, protected by D45.

6 months ago

0 Jared Zhou 6 months ago

TI__Mastermind 20515 points

Hi Johnny,

What's the ESD rating?

BR, Jared

0 Johnny Okeeffe 6 months ago in reply to Jared Zhou

Prodigy 25 points

I need the device to handle +/- 8kV contact and +/- 15kV air discharge ESD pulses using the human body model.

0 Steven Li 6 months ago in reply to Johnny Okeeffe

TI__Mastermind 23150 points

Hi Johnny,

Our expert is currently out of office and will reply to you next Monday. Thanks for your understanding.

Best Regards,

Steven

0 Jared Zhou 6 months ago in reply to Johnny Okeeffe

TI__Mastermind 20515 points

Hi Johnny,

Based on the ESD level on datasheet, I don't think TLC5947 can stand such ESD level.

BR, Jared

0 Johnny Okeeffe 6 months ago in reply to Jared Zhou

Prodigy 25 points

I realize the component alone cannot withstand the ESD, but am hoping that there is an external protection strategy that will work (e.g. additional TVS diodes configured x,y,z way - which is a strategy commonly used to protect most ICs, as 8kV and 15kV are typically far above the standard internal protections).

However, if there is no method that TI recommends to protect this circuit, can you instead propose an alternate component?

0 Jared Zhou 6 months ago in reply to Johnny Okeeffe

TI__Mastermind 20515 points

Hi Johnny,

Do you mean another LED driver which has the same spec with TLC5947 but can stand higher ESD level?

BR, Jared

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TLC5947: Electrostatic Discharge (ESD) Protection