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IC Package to send DC voltage on wider distance to power up the Wireless AC Current Sensor

Other Parts Discussed in Thread: LM2660, TPS560200

I am looking for the IC package which helps me to send DC power supply to more than one LM2760 IC package called Capacitor voltage regulator, which provides 3.3v DC to Wireless AC Current Sensors. I am using a battery powered sensor for current detection and trying to give them the secondary option for external voltage to work with these sensors.

Any suggestion on this will be a great help.

  • Hello again Robson,
    LM2660 is a capacitive charge pump that is unregulated.
    It will need a regulated input to maintain a regulated output.

    Commonly for long loop runs of distributed power a higher input voltage will result in lower loop current and less resistive losses.

    Linear regulators can be used however they are very inefficient.
    Efficiency = Vout/Vin and will not serve well to reduce the overall loop current.

    There are some capacitive charge pumps that are regulated, however their input voltage is usually 5V or less. The low input voltage would be limiting in a long power loop.

    A switcher like TPS560200 will provide up to 500mA from an input of 17V maximum with ~90% efficiency.
    Here is a Webench design I did for you with this device.
    webench.ti.com/.../SDP.cgi
    TPS560200DBVR ‑ 12Vin to 3.30V @ 0.1A 88% efficiency

    This would be able to accept up to 17Vin down to about 4Vin (the power loop with resistive drop) and provide 3.3V at 100mA (The device can do up to 500mA)

    So a 12V source with a few ohms of resistance in the wiring, could be routed to all sensors. Vin at each sensor would vary depending on the distance from the 12V source. By design assure that the voltage drop will not get below say 4V, and use the TPS560200 to create 3.3V at each sensor.

    This would be my recommendation.
  • Actually the the DC power supply is 10 m away from device I need to give suitable output of 3.3v.

    How much power loss will be there if I use this IC package?
  • I can not tell you the total loss, Robson, however the efficiency of the converter is ~88%.
    TPS560200 is a synchronous buck converter, the most efficient of the buck converters.

    To calculate total loss you would need to precisely know the load current.
    The wireless sensor likely has a very transient current profile, it only draws current when transmitting.
    Therefore you would need to calculate the average current, or measure it.

    The resistance of the wire will also add some loss, again you must know the average current being provided.