• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 29 subscribers
  • Views 768 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS570: Device Electrical Specifications for Power Supply Design

Lorenz Gruebler
Expert 1075 points

Hello,

I'am not exactly sure how to interpret the Electrical Specifications of the TMS570. For the Design of the MCU power supply I want to know the max. current drawn at the Vio (3.3V)  rail.

The specification (p. 61) says:

"Input clamp current (total): " +-40mA. Is this the max. current that can be drawn by ALL I/Os at the same time?

Formula:

--> I/O Current maximum = Input clamp current (total) + Iccad (operating mode) + Iccp (erase/program mode)

--> I/O Current maximum =40mA + 30mA + 90mA = 160mA  (anyhow, there will be never a program erase and a AD sampling cycle at the same time)

Is this correct or how do I get the max. current consumption for the Vio (3.3V) rail?

 

regards,

Lorenz

 

 

  • 0
    TI__Mastermind 49120 points

    Hi Lorenz,

    The input clamp current is an absolute maximum specification. This is the maximum current that can flow safely into an input terminal of the microcontroller at voltages above or below the normal specified operating range.

    For power supply design, you can use the numbers in the table titled "Electrical Characteristics Over Operating Free-Air Temperature Range" on pages 62 - 65 of the datasheet (SPNS141F). Note that the VCCIO supply current draw is specified with no DC load on the output terminals.

    Regards, Sunil

  • 0 in reply to Sunil Oak
    Expert 1075 points

    Thank your for your reply

     

    Lorenz