• Difference between LT8645S and LT8645S-2


    what is the difference between  LT8645S and LT8645S-2?

    I can see on the datasheet of  LT8645S-2 that the only difference are:

    1)  LT8645S-2 does not have internal caps

    2) and availability of 150C rated temperature part. 

    Is that all the differences are…

  • LTPowerCAD vs LTSpice efficency calcupation for LT8645S

    Hi all,

    we have checked the efficincey calculation for LT8645S both in LTPowerCAD and LTSpice and it looks that the LTSpice simulation gives higher than expected efficiency. Calculation method for Spice is taken from example. E.g. for Vin 12V, Vout=5V…

  • LT8645S Enable

    The input voltage for LT8645S is 41V with a minimum input voltage of 10V. The output voltage is 12V.

    Design 1:

    Enable pin is tied to Vin pins through resistor divider network. As per the formula mentioned in datasheet, Ven= 7.88V. However the Vout starts…

  • LT8645s efficiency measurement

    I would like to measure power consumption of LT8645S on LTSpice, but the result is not realistic. I found 11W average power on LT8645s instead of 1W on LT8646s for the same schematic.

  • LT8645S inverting output

    Can I use LT8645S as inverting regulator like LTM module?

  • LT8645S Mode Pin

    Is it possible to change the Mode Pin setting while the device is running?

    I'd like to run the LT8645S in Burst Mode while in  "low-power/standby" state. Once a 'wake' signal is detected, I would then like the ability to change to Spread Spectrum…

  • Constant current souce using LT8645S

    I've designed a constant current source based upon the LT8645S.  See attached. It works well when the load is around 1-2Ω.  But when I increase the load to 3-4 ohms, the current drops significantly.

    The input voltage is 42V, but the output voltage…

  • LT8645S under voltage lockout behaviour

    I am using a LT8645 to get 5V from 24V to 48V.
    The secondary power supplies are sourced by this 5V rail, which is buffered with 3500uF,
    while the 24V/48V input is buffered with 4.8uF.

    In the case of an emergency shut down (24V cable hot plug off), I have…

  • Problem with LT8645S output exceeding 25V


       I want to output 40V 6A with LT8645S.According to the design of LTpowerCAD II V2, the design schematic diagram is as follows.

    Because LTpowerCAD II v2 has a saying, "For Vout>3.3V, tie BIAS to Vo ", so I directly connected BIAS to the output…

  • LT8645S keep on short cutting when power off


    We have a problem with the LT8645S that keep on being destroyed  when first power off. The debug has done.The following steps are:

    1.The board first power on,it works well. The Vout is 24V. That sound exciting.But When power off, I find that lt8645s…