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TPS61070: TPS61070 power supply for LED.

Part Number: TPS61070
Other Parts Discussed in Thread: TPS61040,

Hi all,

Like TPS61070 as TPS61040,
Is it possible to use it as an LED power supply?

Also, when TPS61070 can be used as LED power supply,
I think that it is safer to insert a clamp diode in parallel with the LED.
Are there recommended clamp diodes?

Best Regards,

watanabe

  • yes. you can refer to the page 17 of the datasheet.
    a 4.7V zener diode can be use to clamp the LED voltage in case that the LED is damaged
  • HI Jasper,

    I appreciate for your support.

    I understand 4.7V zener diode can be use to clamp.

    Q.Is there a recommended Zener diode model number?

    Best Regards,
    watanabe
  • the zener can't in parallel with the LED directly. place a 1K resistor between current sensing resistor and the FB pin. the zener is connected between VOUT PIN and FB PIN. as the zener diode current is limiting, you can select a small zener diode from Mouser.
  • Hi Li,

    Thank you for your support.

    I have an additional question.

    Q1.
    >the zener can't in parallel with the LED directly.

    Referring to the TPS 61040 EVM - 002 user guide (SLVU 068 A)
    The LED is inserted between VOUT PIN and FB PIN.
    Since it is inserted between the zener diodes VOUT PIN and FB PIN,
    Is the LED and Zener diode in parallel?


    Q2.
    >place a 1K resistor between current sensing resistor and the FB pin.

    Is the purpose of this resistor to reduce the current flowing into the FB pin and increase the efficiency?
    Is this resistance essential?


    >the zener is connected between VOUT PIN and FB PIN.
    >as the zener diode current is limiting, you can select a small zener diode from Mouser.
    I understood the above.

    Best Regards,
    watanabe