TPS61042 CTRL enable Ton time

In the datasheet the "ton" spec for minimum CTRL pulse width to enable is 500uS.  I've got an application where code was written targeting 500uS but due to tolerances the pulse could be as low as 457uS.  The spec test conditions were for -40 to 85C.  If actual operating range is 0-40C and voltage is 3V can there be any guarantee that the part will operate correctly or will software need to be re-written?

  • Hi Mike,

       To answer your question about MIN specified in the datasheet, this is indeed the MIN required over the operating conditions specified, no fudge-factor allowed!  While it may be possible that some devices may work outside the specified range, there is no guarantee that all devices will, as process variations cause subltle variations in the operation. 

      Having said this, I'm looking at the TPS61042 datasheet, ( http://www.ti.com/lit/ds/symlink/tps61042.pdf ) and on page 3, I see CTRL Ton is 50uS, not 500uS.  Also, page 10 Fig 16 shows TON Enable MIN of 50uS, so I'm not sure where you got the 500uS figure, and indeed, if the Ton is 457uS, no problem.

      Let me know if I have missed something, but the answer to the basic question is > the specification must be adhered to. 3

    -Leonard

     

  • In reply to LeonardEllis:

    Thanks for the reply Leonard.  The datasheet we were viewing was version SLVS441B.  I can see that the spec was updated in version SLVS441C to 50uS so we should be all set.