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XTR111: XTR111 without a drive transistor

Part Number: XTR111
Other Parts Discussed in Thread: TPS92612-Q1, LP5560

Hi. I would like to use the XTR111 to drive a standard red LED. Can I use this part without a drive transistor (Q1 in data sheet front page) and if so how could I do this?

Thankyou.

  • As far as I can see, the XTR111 always requires an external P-channel FET.

    It would be easier to build the LED driver from an opamp and discrete FET, or just an opamp. What are the supply voltage(s) and the required ranges of input voltages and output currents?

    Alternatively, it might be possible to use a specialized LED driver like the LP5560 or TPS92612-Q1.

  • Hi Abdul,

    See the following excerpt from the XTR111 datasheet.

    The XTR111 is designed to be operated with an external MOSFET to drive the output current. Without the MOSFET, it will be difficult to control the voltage compliance of the XTR device. Is there a reason why an external MOSFET is undesirable for your application?

    I agree with Clemens' suggestions. If you want more information on specialized LED drivers, you may refer to the product overview page: https://www.ti.com/power-management/led-drivers/overview.html

    Regards,

    Zach