DRV8711: SDATO have problem

Lam Phan Huynh

Prodigy 160 points

Other Parts Discussed in Thread: DRV8711

Dear !

i design schematic with DRV8711 and dspic33. I have problem: SDATO pin can't output? This is my code

SLEEP_pin=0;

delay_ms(1);

RESET_pin=1;

delay_ms(1);

RESET_pin=0;

delay_ms(1);

SPI_READ (0x80);

CS&CLK

SDA&CLK

SDAO&CLK

Schematic

please help me!

over 11 years ago

0 Nicholas Oborny over 11 years ago

TI__Mastermind 21320 points

Hi Lam,

Are you able to WRITE to the device? You can try toggling the ENABLE bit to see if the DRV8711 becomes active.

Can you try increasing the wait period to 10ms before the READ? Are you sure that the micro is delaying the proper amount of time?

0 Lam Phan Huynh over 11 years ago in reply to Nicholas Oborny

Prodigy 160 points

hi !

i will try now, thanks you. can you tell me detail more ?

0 Lam Phan Huynh over 11 years ago in reply to Lam Phan Huynh

Prodigy 160 points

i just try it, but it is not ok, can you help me?

0 Nicholas Oborny over 11 years ago in reply to Lam Phan Huynh

TI__Mastermind 21320 points

Hi,

Try the SPI communication one more time with nSLEEP = HIGH.

If the DRV8711 is not responding at then perhaps there is an issue with the board. Can you set nSLEEP = HIGH and RESET = LOW then measure VM, VINT, V5, and nFAULT.

What VM voltage are you operating at?

0 Lam Phan Huynh over 11 years ago in reply to Nicholas Oborny

Prodigy 160 points

HI !

i just try with nSLEEP=HIGH, RESET=LOW, VM=24V, VINT=2V, V5=5V, nFAULT=HIGH but SDATO is not output.

0 Wilson Zuo over 11 years ago in reply to Lam Phan Huynh

TI__Mastermind 26065 points

Hi Lam

Do you have an external pull up for the SDATO pin as it is an open drain output?

Thanks.

0 Lam Phan Huynh over 11 years ago in reply to Wilson Zuo

Prodigy 160 points

hi!

i use external pull up (6k8). i just have made a new board DRV8711 for testing again.thanks

0 Lam Phan Huynh over 11 years ago in reply to Lam Phan Huynh

Prodigy 160 points

dear all !

thanks you! My board is ok, i have problem with old board, the new board work ok.

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DRV8711: SDATO have problem