TLC59291: Accessing control data latch in TLC59291

Hi, Twinkle,

Sorry for the touble you're facing now.

If you are using the timing diagram, e.g. the Function Control Data Write Timing in figure 13, the control data should be OK to be sent into the driver.

Would you please give me a screen shot of your waveform for SIN / SCLK / LAT so that I can check about it?

Thanks.
Regards,
Kenneth

Hi Kenneth,

May i know that latch pin should be configured as a gpio or it will be configured as a SPI slave select pin.How to send data on control data latch.

Thanks in advance.

Regards,

Twinkle.

Hi, Twinkle,

Either using GPIO or the slave selcet pin can generate the Latch signal.

But please make sure the latch pulse is following the timing diagram in datasheet.

Please let me know if this solves your problem.
Thanks.
Regards,
Kenneth

Hi Kenneth,

I have used latch pin with GPIO or SS pin both but not succeeded.

Can you please provide me sample example code for SPI.

I am sending  you screen shot SIN / SCLK / LAT.

Consider pin in different color on oscilloscope as follows-

Yellow  ----  SCLK

Blue     ------  SIN

PINK    ------  LAT

If you need any more information please let me know.Kindly provide SPI example code also.

Hi, Twinkle,

I'm wondering why your lat signal is in the front.

As you can see from the following figure, the block in red line should be a whole data array. And the lat is added after 16 SCLK.

I also attach the sample code of TLC59283 here for your reference, which should be similiar to TLC59291 code.

6545.TLC59283_Sample Code.zip

Please let me know if this solves your problem.
Thanks.
Regards,

Kenneth

Hi Kenneth,

I have given the LAT signal after the SIN as you said still i am not  getting the data on SOUT pins. the waveform of the SIN , SCLK and the LAT is attached in the figure.

Figure Instructions

Yellow --> SIN

Blue ---> LAT

pink--> SCLK

Thanks.

Regards,

Twinkle 

Hi, Twinkle,

It seems your latch is still in the front and the SCLK is still 8, not 16.

Would you help to check?

Thanks.

Regards,

Kenneth

Hi Kenneth,

sorry, In previous reply i have send you the the wrong waveform image . this is the correct one.

I have also attached my  c source code snapshot .can you check for me  what i am doing wrong.

Image Description:

SIN--> yellow

SCLK  -->pink

LAT -->Blue

Thanks.

Regards,

Twinkle

Hi, Twinkle,

The timing is OK and let me check another item.

There are two kind of data you need to send, one is control data and another is output ON/OFF data.

As you can see from datasheet 8.5.1, "When SCLK is '0' at LAT rising edge, the 16-bits common shift register are copied into the output on-off data latch. Also when SCLK is '1' at LAT rising edge the 16-bits data are copied into the control data latch."

According to your waveform, you are sending the ON/OFF data. So do you send control data before this? If not, the control data will be default value and from Table 8 and Table 11, BLANK will be set as SOUT mode so even you set BLANK = Low, the output cannot turn ON.

So please check about this and if you don't send control data please send the control data.

Please let me know if this solves your problem.

Thanks.

Regards,

Kenneth

Hi,Kenneth,

I am sending the control data too before output on /off data .

At SCLK =1 I am sending control data

At SCLK=0 I am sending the ON/OFF data

but still i am not getting any output on SOUT pins .  I am attaching wave from for both control data latch and output on off data latch .

and can you please tell me what should be the blank mode  and blank pin value for getting  the outputs on the SOUT pins.

The wave from for control data is

Image Description:

Yellow --> SIN

Blue -->SCLK

Pink--> LAT

The wave form of ON/OFF Data is

Image Description:

Yellow --> SIN

Blue -->SCLK

Pink--> LAT

Green--> Blank

Thanks.

Regards,

Twinkle

Hi, Twinkle,

Do you mean there's no output at SOUT pin?

No matter how you confirgure BLANK, data can be clocked out at SCLK rising edge.

Can you provide the SOUT waveform?

Do you get the OUT0 - OUT15 turn on as you expect?

Thanks.

Regards,

Kenneth

Please make sure 

Hi, Kenneth,

No, I am getting output on SOUT pin. but there is no output on OUT0-OUT15 pins. whereas No matter how i configure the blank mode i am not getting anything on OUT0-OUT15 pins .

I am attaching the waveform of SIN, SCLK, LAT and SOUT pins .  I have sent this ( 0b0000000011111111) data on SIN pin .

image Discription

Yellow--> SIN

Blue --> SCLK

pink --> LAT

Green --> SOUT

can you please tell me what i am doing wrong .

Thanks.

Regards,

Twinkle

Hi, Twinkle,

Please try the following steps to quick test the OUT ON/OFF function:
1. After power on, control data latch Bit[9] is default 0, which is SOUT mode, and if BLANK pin is set as HIGH, it works as 16ch device, if BLANK pin is LOW it works as 8ch device. Please make sure you choose correct ch.
2. From your former information, you're using 16 ch, so you need to set BLANK high after power on.
3. Send 16 bit ON/OFF data and after latch signal, the output should work as you expect.

Please send me your waveform of the above steps for SIN SCLK LAT and BLANK if it still not works.

Thanks.
Regards,
Kenneth

Hi, Twinkle,

Do you solve this problem?

Thanks.
Regards,
Kenneth

Dear Sir,

The code that you have shared for TLC 59291 IC  was on GPIOs.

Kindly, provide me the sample code for SPI interface to send the data serially.

Also, suggest the solution for the following:

1. The Output which we send for the OUT pins(OUT0- OUT15) of the IC TLC59291 does not remain constant.

2. Their is huge voltage drop form 2.8V to 0.5V without any change in code, this voltage drop occurs.

Looking forward in anticipation for your support.

Thank You,

Kind Regard,

Twinkle

Hi, Twinkle,

Currently we don't have software resource to provide SPI code.

But since it's 16 bit data, there should not be big difference to use SPI and you can use an I/O or CS of SPI to senerate LAT signal.

How do you test the current? And where do you test for the voltage drop? Did you test the OUT voltage?

Thanks.
Regards,
Kenneth

Dear sir,

Yes,We have checked the voltage on OUT pins ie. OUT0-OUT15 pins of IC TLC59291 by multimeter.And we are checking voltage drop on OUT pins of IC TLC59291.

Thanks,

kind Regards,

Twinkle

Hi, Twinkle,

Another thing I want to check, do you send the data all the time?

I suggest you to use the oscilloscope to measure the voltage on OUT and the current of the same channel first.

Thanks.
Regards,
Kenneth

Dear Sir,
Kindly provide me proper information and sample code regarding SID register,As datasheet of TLC59291 is not enough to acces SID register.Please provide me proper information that how and when to read SID register.
Thanks
Regards,
Twinkle

Hi, Twinkle,

Sorry but we don't have the SID read code currently.

Please refer to datasheet 8.4.7.

If you think this answers your question, please help to click "Resolve".

Thanks.
Regards,
Kenneth