TAS5707 PLL autolock error

Lukas Osmancik

Other Parts Discussed in Thread: TAS5707

I am debuging new design with TAS5707 + ARM M4 + MEMS microphone.

I cannot get any sound from TAS5707.

I am running on fs=16kHz, BCLK=768kHz MCLK=6,144MHz

I am using MCU crystal which is 8MHz so the master clock is generated internaly by dividing and droping cpu clocks - so there is some jitter.

How much is TAS5707 tollerant to MCLK jitter?

When I read register 0x00 I get 0b10010000 so I suppose that TAS5707 detect my setup Fs=16kHz and MCLK =384xFs correctly

Then when I read error status register I get autolock error bit . What this bit means?

My design is based on TI EVM module schematic.

When I scope MCLK it looks little "nervous". When I scope audio power outputs there is zero signal.

Regards

Luke

over 11 years ago

0 Lukas Osmancik over 11 years ago

Prodigy 110 points

I read a lot about users experience with TAS devices on this Forum.

I know that I must clear error register but there is autolock error again.

0 Don Dapkus over 11 years ago in reply to Lukas Osmancik

TI__Guru**** 189399 points

Hi, Lukas,

Yes, e2e is a great reference!!!

I have asked my colleague to look into your specific situation.

-d2

0 Ravi Singh over 11 years ago

TI__Mastermind 22965 points

Lukas,

The I2S clock rates you mentioned are not valid for the device.

-- SCLK should either be 32*Fs or 64*Fs

--The supported MCLK rates are also shown in data-sheet (Register 0x00 description section).

With valid clock rates/ratio's the clock error issues you reported should be fixed.

-Ravi

0 Lukas Osmancik over 11 years ago in reply to Ravi Singh

Prodigy 110 points

Thanks for reply.

I made corrections in MCU registers to pass TAS5707 requirements.

Now I have Fs=16kHz (real value 160010Hz), SCLK=512kHz (real value 510.1 - 513.2kHz), MCLK=6.144MHz ( real value 5.882-6.270MHz)

The autolock error is still present.

My sw startup:

AMP_PDN_NORMAL; //NO PDN

AMP_RESET; //TAS5707 RESET

delay(); //200ms

AMP_NORMAL; //TAS5707 normal operation

delay(); //200ms

I2C_WriteRegister(0x1B,0x00); //trim osc

delay(); //120ms

I2C_WriteRegister(0x07,0x30);

delay();

I2C_WriteRegister(0x05,0x00);

delay();

I2C_WriteRegister(0x06,0x00);
I2C_WriteRegister(0x02,0x00);

I order new XTAL for MCU to pass I2S frequencies more accurately

Lukas

0 Lukas Osmancik over 11 years ago in reply to Lukas Osmancik

Prodigy 110 points

I have still autolock error.

When I read register 0x1B there is 0b11000000 so the trim was done O.K.

Are there some measurable waveforms on some TAS5707 pins for determination if there is no problem with external components?

I dont have in my design a throu-holed area under TAS5707 cooling plate as is done on EVM board (I am running with 12 OHM load). I dont have this cooling plate connected to any potential (I dont noticed any instruction for this plate in datasheet).

Any idea where is problem?

0 Lukas Osmancik over 11 years ago in reply to Lukas Osmancik

Prodigy 110 points

Today I was successful there was problem with cold soldering on some pin - now TAS5707 works.

Thanks for support

Lukas

Audio

Audio forum

TAS5707 PLL autolock error