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TPS7A4201: need a +/-20V output tolerant solution

Part Number: TPS7A4201

hi,

I'm looking for a power amp to supply a Nordig device (STB app).

Input is 12V +/-15%, output 5V +/-3%, max output current 40mA, max load 100uF, w/ EN, and must be +/-20V tolerant on the putput pin/connector...

we have a solution w/ discre components (lots of R, diodes, etc.) so was looking for something cost effective (like an opamp) but that could allow space saving (smaller BOM)...

I was thinking maybe the TPS7A4201 with a diode between the output and the voltage divider to program the VOUT (the feedback pin will be protected as the voltage divider will limit the current throughthe ESD as >100KOhm)...

what do you think?

thanks a lot in advance

KR

Vincenzo

  • Hi Vincenzo,

    From your description of the application TPS7A4201 does sound like it may be a good candidate, but I would like to better understand the requirement for the +/- 20 V tolerant output.  What is driving this requirement?  What will Vin be when Vout is 20 V?

    Please note that while TPS7A4201 is able to have 20 V on the output, it does not have built in reverse current protection; therefore, Vin must remain higher than Vout.  Furthermore, TPS7A4201 is not able to have a negative voltage applied to the output with respect to the LDOs GND pin.

    Placing a diode in the feedback loop may be tempting; however, this can cause serious stability problems and is not recommended. 

    Very Respectfully,

    Ryan

  • hi Ryan,

    thanks for the support.

    The app is supply for Nordig 2.0.6.1 Antenna, whose Specifications are:

    • 5-5.2Vout+/-3% with 30mA minimum with +/- 15V (Input is from wall jack @ 12V)
    • Protection is needed at the output (+/-20V tolerant, >50KOhm output imp. in disable mode

    EE is a STB.

    I can send you offline the discrete solution (+/-28V tolerant on out) we have at the moment, but we are looking for a more integrated solution...

    thansk a lot in advance

    KR

    Vincenzo

  • Hi Vincenzo,

    With the positive and negative requirements it does not sound like an LDO will be able to fit your application on its own and a discrete solution is in order. We will follow up with you via private message to discuss forward and are considering this e-mail thread closed.

    Very Respectfully,
    Ryan