About Power Shift Dimensioning

The Power Shift Dimensioning tool calculates the external resistors needed for the Power Shift feature of the LITIX™ Basic+ TLD1114-1EP based on the system requirements. In addition, it provides a graphical representation of the output current split between the internal power stage and the power shift circuit as well as the power loss over the device and the power shift resistors over the supply voltage.

For the calculation, select the configuration of the power shift – With MOSFET or Without MOSFET - from the Schematic section and then enter the system requirements in the blue-colored parameters:

  • the minimum supply voltage VS(min)
  • the maximum supply voltage VS(max)
  • the ambient temperature TA
  • the thermal resistance of the TLD1114-1EP RthJA
  • the overhead voltage for the power shift limitation VOVERHEAD
  • the output voltage VOUT
  • the output current IOUT
  • the typical RDSON of the selected MOSFET
  • the typical VGS(typ) of the selected MOSFET

Parameters RDSON and VGS(typ) have to be configured only for the configuration With MOSFET. A low VGS(th) voltage is especially important when high currents are used, as otherwise the power loss of the driver might exceed the desired limit. This can happen when the power shift circuit is activated at higher supply voltages due to a higher VGS.

Based on the inputs, the power shift resistors R1 and R2 (R1 only for the configuration Without MOSFET) are calculated as well as the output current reference resistor RSET.

The Current split chart shows the current split between the TLD1114-1EP internal power stage and the power shift circuit over VS. The Power loss split chart shows the Power loss of the TLD1114-1EP and the power resistors R1 and R2 over VS.

The configuration is indicated as pass or fail in the Summary section. The recommended configuration for the CFG and OUTL/OUTH pins is provided as well as the calculated maximum power loss of the TLD1114-1EP and the power resistors R1 and R2.

For further information regarding the Power Shift feature please consult the LITIX™ Basic+ TLD1114-1EP data sheet and the LITIX™ Basic+ TLD1114-1EP Power Shift application note in the following links:

  • LITIX™ Basic+ TLD1114-1EP data sheet
  • LITIX™ Basic+ Power Shift feature of TLD1114-1EP application note

To see user manual please click here.