TLC59116: TLC59116

Martin Gudbjerg

Part Number: TLC59116

Hi,

I'm facing the same EMI issue as the customer of Mr. Leroy Song; A significant frequency harmonic at 163 MHz and at higher harmonics as well.

Any app note or design guide for solving this issue?

Any idea if this noise radiates from the TLC59116 casing or from its pins/ wires and how to attenuate it?

So far, not to much luck using chip ferrite beads and ceramic capacitors at the supply pin...

Kind regards, Martin Gudbjerg

over 4 years ago

0 Frank Qiu over 4 years ago

TI__Genius 15776 points

Hi Monet, could you help in this case.

0 Monet Xu over 4 years ago

TI__Genius 9255 points

Hi Martin,

Could you please provide the configuration of registers and which LED function now you design to achieve?

and which pin or where do you capture the harmonic?

Best Regard

Monet Xu

0 Martin Gudbjerg over 4 years ago in reply to Monet Xu

Prodigy 10 points

Hi Monet,
Thank you for your answer.

TLC59116 register use:
Mode1 = 0
Mode2 = 0x08

LEDOUT0->LEDOUT3, We use:

Mode=0, for LED OFF
Mode=2, For LED ON
Mode=3, for LED blinking

PWM0->PWM15, we use them all with different settings, depending on user setting.

IREF, is default value, and not changed.

The complete circuit uses two TLC59116's one with Rext=2k2 ond one with Rext=750R

LED's are supplied with 5V.

The harmonic seems to come from the VCC pin 27 (3V3).
As mentioned, no significant damping observed when extra decoupling capacitors and chip ferrite bead (1Kohm/100MHz) was mounted at pin 27.

Kind regards, Martin

0 Frank Qiu over 4 years ago in reply to Martin Gudbjerg

TI__Genius 15776 points

Hi Monet please help to keep following this case

Power management

Power management forum

TLC59116: TLC59116