65W PoE DC-DC converter


Posted on Feb 6, 2014

A solution to one aspect of Power over Ethernet (PoE) is presented here utilizing the ON Semiconductor NCP1031 series of monolithic, high-voltage switching regulators with internal MOSFET. The application note provides details for constructing an inexpensive, high efficiency, 5. 0 V DC power supply with a power output of 5. 0 to 6. 5 W, (output power


65W PoE DC-DC converter
Click here to download the full size of the above Circuit.

is conversion mode dependent ” see DC/DC converter operation description below). The associated input circuitry for responding to PoE detection and classification protocol is also included. ON Semiconductor can provide a demonstration printed-circuit-board (PCB) with this circuitry upon request. As a result of IEEE Standard 802. 3AF, it is now possible to inject DC power through Ethernet data transmission lines to power Ethernet communication devices as long as the end power requirement is less than 13 W. The parametric details of DC power transmission and the associated terminology is outlined in this IEEE document. POE consists of two power entities: Power Sourcing Equipment (PSE) and Powered Devices (PDs). The PSEs typically provide 48 Vdc nominal to the LAN cables while the PDs are small DC/DC converters at the load end of the cables which transform the 48 V to logic levels such as 5. 0 Vdc or 3. 3 Vdc or both, to power the communications equipment. The PDs should be able to operate with a maximum average input power of 12. 95 W and tolerate an input voltage range of 36 to 57 Vdc. In addition, a certain "protocol" is required in which the PD is detected (Signature Mode) and then classified (Classification Mode) according to its maximum power level. Note that from the 4th and 5th columns on the table, that the current drawn from the PSE falls between the Iclass minimum and maximum values for a given power...




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Distortion Analyzer
    Closed-Loop Peak Detector Circuit
    NE612AN NE612 mixer / oscylator RF
    P8 CPU Documentatio Hardware
    USB FM Transmitter for MP3 Player
    ultrasonic electrostatic transducer for
    RF amplifier circuit diagram
    Economy radar detector
    Vacuum tube audio amplifier
    RPM switch for 6th ports or VDI
    Elderly lost alarm circuit
    555 make use of digital amplifier circuit diagram
    High-voltage isolation switch operation display circuit
    Broadband using negative feedback amplifier circuit



    Top