DAC38J84: Specifications

Vigneshwar Raj

Prodigy 245 points

Part Number: DAC38J84

Hello all,

I am planning to use DAC38J84 DAC in following mode.

Mode : (LMF = 442)

interpolation x8

Sampling frequency : 2.4576GHz.

I checked in datasheet. LMF 442 mode current details are given with lowest sampling frequency.

Can you provide the exact current requirement for this mode?

Thanks,
Vignesh

over 3 years ago

0 jim s over 3 years ago

TI__Guru* 91947 points

Vignesh,

Will you be using the DAC PLL? Will you be using the NCO's?

Regards,

Jim

0 Vigneshwar Raj over 3 years ago in reply to jim s

Prodigy 245 points

Hi Jim,

Please find my replies.

Will you be using the DAC PLL?

Reply: No, I am planning to give 2.4576GHz directly from PLL.

Will you be using the NCO's?

Reply:Yes, I will use.

Regards,
Vignesh

0 jim s over 3 years ago in reply to Vigneshwar Raj

TI__Guru* 91947 points

Vignesh,

Here is some power measurements taken that are close to your setup.

Regards,

Jim

3107.POWER SUPPLY MEASEREMENTS.pptx

0 Vigneshwar Raj over 3 years ago in reply to jim s

Prodigy 245 points

Hi Jim,

Thanks for your immediate response

As I said previously, I required the power details for LMF-442 (No of Lanes = 4) Hence JESD204B block should be turned on.

Number of Converters to be used is 4. Hence all the four DACs to be turned on.

Please refer the following E2E link.

https://e2e.ti.com/support/data-converters-group/data-converters/f/data-converters-forum/1042657/dac38j84-jesd-mode-selection

Please provide the power details with the mode Configuration PPT (provided by Mr. Neeraj) attached in the above link.

Regards,
Vignesh.

0 jim s over 3 years ago in reply to Vigneshwar Raj

TI__Guru* 91947 points

Vignesh,

This will require modifying an existing EVM and connecting several external power supplies. Due to the fact most employees are now on holiday break, we will not have anything for you until the first or second week of January.

Regards,

Jim

0 Vigneshwar Raj over 3 years ago in reply to jim s

Prodigy 245 points

Hi Jim,

Awaiting for your reply.

Regards,
Vignesh

0 jim s over 3 years ago in reply to Vigneshwar Raj

TI__Guru* 91947 points

What frequency will the NCO be set to? You are using an external 2.4576GHz clock, correct? The board is being modified and we should have power numbers by the end of the week if all goes well.

0 jim s over 3 years ago in reply to jim s

TI__Guru* 91947 points

Vigneshwar,

With your settings and the NCO running at 1GHz, here are the power numbers:

0.9V_VDDDIG = 410mA

all other 0.9V = 231mA

1.8V = 57.7mA

3.3V = 115.2mA

With your settings and the NCO running at 100MHz, here are the power numbers:

0.9V_VDDDIG = 407mA

all other 0.9V = 227mA

1.8V = 49.5mA

3.3V = 115.2mA

Regards,

Jim

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DAC38J84: Specifications