• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 99 subscribers
  • Views 187 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

AM5728: Changing from pullup to pulldown on sysboot pins

Hideaki Matsumoto
Expert 8740 points
Part Number: AM5728

Hi,

 

The customer wants to switch two kinds of sysboot below, it depends on their some products.

Sysboot[5:0] = 0b00 0101

Sysboot[5:0] = 0b11 0101

 

In order to change the above sysboots without layout change, they’re considering to add another pull-down register on sysboot[4] or [5] to change from pull-up to pull-down as follows.

 

In the case of 0b11 0101, both 3.6k ohm pull-up register and 10k ohm pull-down register are connected on each sysboot[5] and [4] pin as pull-up.

For the case of 0b00 0101, 1.2k ohm pull-down register is added in parallel to ensure 1.07k ohm pull-down register (10k + 1.2k in parallel) on each sysboot[5] and [4] pin.

 

Is this no problem ?

 

 

Regards,

Hideaki

  • 0
    TI__Guru**** 393215 points

    Hi,

    The SYSBOOT pins have Dual Voltage LVCMOS I/O buffers. You must ensure that the resistive dividers meet the required input level thresholds listed in Table 5-17 from the AM572x Datasheet SR2.0 Rev. F. Note that there are different input level thresholds depending on the supply voltage for the I/O cells.