• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 14 subscribers
  • Views 852 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.

TPS7A4501-SP: Minimum input voltage

Evan Livingstone-White
Prodigy 80 points
Part Number: TPS7A4501-SP

What is the absolute minimum input voltage on this device such that internal circuits (error amplifier) function properly?

If my input is 1.9V and my desired output is 1.5V with a load current of 300mA then should everything operate correctly? Figure 1 in the datasheet suggests that even with a 500mA output current at 125degC the dropout would be <200mV. Therefore I would still have 200mV headroom. Is that correct?

  • 0
    TI__Expert 7445 points
    Hi Evan,

    As highlighted in the datasheet there are two packages one rated for up to 0.75A and other rated for 1.5A.
    Which package are you considering for your application. Note it is important to look at the electrical table for the worse case dropout voltage. Figure 1 only highlights typical dropout voltage.
  • 0 in reply to Ramesh Khanna
    Prodigy 80 points

    Hi Ramesh,

    I am using the 5962-1222402VHA. The datasheet states worst case that Vin,min = 2.3V for 500mA at 25degC where the adjust pin is connected to the output pin. It also states that at 500mA load with the output programmed to 2.4V the maximum dropout is 0.33V.

    My question is: suppose I had an input of 1.33V and a desired output of 1V with a maximum 500mA, would the chip still regulate properly? Or is there some minimum voltage required for the internal circuitry to operate properly (such as the error amplifier).

    Thanks!

  • 0 in reply to Evan Livingstone-White
    TI__Expert 7445 points
    Hi Evan,

    Output voltage must be greater than the internal reference i.e. 1.246V over full range. As highlighted in the datasheet input voltage must be greater than 2.1V ( typ) and 2.5V (max) for the internal bandgap and to ensue we can drive the pass PNP element effectively.