• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 428 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.

TPS92661-Q1: LED Constant current driver requirements

c tyerman
Prodigy 150 points
Part Number: TPS92661-Q1
Other Parts Discussed in Thread: TPS92691-Q1, TPS92515, TPS92518, LM3409, TPS92691

Im looking at using the TPS92661-Q1 to control a mixed colour matrix of lumiled luXEon C LEDs (4 mixed colour 10 LED arrays)

it looks to me that by default (before configured) TPS92661-Q1 will short across the led driver and the effective forward voltage across the led array will jump whenever any led is switched

ive seen mention of using a TPS92515 but, that means the input voltage must be greater than the total LED forward voltage

i have a previous buck-boost circuit using a TPS92691-Q1 originally from webbench for this led array but am unsure if will work with the TPS92661-Q1

what would be the recommended driver for use with this chip and is it possible to get webench to create a circuit for it

  • 0
    TI__Mastermind 28655 points

    Hello,

    The TPS92661 needs a current source that can change output voltage quickly. The TPS92515 is a buck converter hysteretic controller as well as the LM3409 and TPS92518. These are all buck converters. A voltage boost can be added before the buck stage to be able to use these parts.

    The TPS92691 was not intended for Shunt FET dimming which is what the TPS92661 effectively does.

    Best Regards,