TMS320C6678: load transient response

Shay Mor

Intellectual 870 points

Part Number: TMS320C6678
Other Parts Discussed in Thread: LM10011, TPS53355

hi,

At 1.4Ghz TMS320C6678

What is the maximum load transient response on etch rails?

1. CVDD

2. CVDD1

3. DVDD15

4. DVDD18

over 5 years ago

0 Bill Taboada over 5 years ago

TI__Mastermind 42545 points

Hi Shay,

We don't provide that information because it is very dependent on the power used by your application. You can use the power consumption model to determine the current requirements for each voltage at peak and idle states to determine the expected transients for each.

Regards, Bill

0 Shay Mor over 5 years ago in reply to Bill Taboada

Intellectual 870 points

Hi,

Could you please tell me the minimum and maximum current possible?

0 Bill Taboada over 5 years ago in reply to Shay Mor

TI__Mastermind 42545 points

Hi Shay,

As I said, we don't have that information due to the variability from design to design. The power consumption model is the only information we provide on the current used by the part.

Regards, Bill

0 Shay Mor over 5 years ago in reply to Bill Taboada

Intellectual 870 points

Thanks,

another question,

For the 1.4Ghz TMS320C6678 with the LM10011,

1. What is the start code value that I need for the start?

for now I have this:

2. Is the EN pin of LM10011 need to connect to TPS53355 EN pin? or pull high regularly? (Z21 or R315)

0 Tom Johnson 16214 over 5 years ago in reply to Shay Mor

TI__Mastermind 46460 points

Shay,

Please refer to the Hardware design guide for KeyStone I devices Application Report (SPRABI2D) in Section 2.2.1 to learn more about the VID codes and the associated voltage. Note that the 1400MHz devices have a separate set of voltages that are 50mV higher for each code than the VID table for the lower speed devices.

Also refer to the C6678 Data Manual in Section 6.2 and Table 6-2 for the initial voltage. For 1400MHz devices, the initial voltage must be 1.15V, nominal. Then after the VID code is generated after reset release, the VCNTL pins will transmit the specific VID code for that device. This is described in DM Section 7.3.4.

The LM10011 VID DAC can be used with many different analog power converters. Please see the E2E link below for additional guidance:

Tom

0 Tom Johnson 16214 over 5 years ago in reply to Tom Johnson 16214

TI__Mastermind 46460 points

Shay,

Here is another very useful E2E post:

Tom

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TMS320C6678: load transient response