LTC4267IGN-1

FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ LTC4267-1 Power over Ethernet IEEE 802.3af PD Interface with Integrated Switching Regulator DESCRIPTIO The LTC®4267-1 combines an IEEE 802.3af compliant Powered Device (PD) interface with a current mode switching regulator, providing a complete power solution for PD applications. The LTC4267-1 integrates the 25k signature resistor, classification current source, thermal overload protection, signature disable and power good signal along with an undervoltage lockout optimized for use with the IEEE-required diode bridge. The LTC4267-1 provides an increased operational current limit, maximizing power available for class 3 applications. The current mode switching regulator is designed for driving a 6V rated N-channel MOSFET and features programmable slope compensation, soft-start, and constant frequency operation, minimizing noise even with light loads. The LTC4267-1 includes an onboard error amplifier and voltage reference allowing use in both isolated and nonisolated configurations. The LTC4267-1 is available in a space saving, low profile 16-pin SSOP package. Complete Power Interface Port for IEEE 802®.3af Powered Device (PD) Onboard 100V, UVLO Switch Precision Dual Level Inrush Current Limit Integrated Current Mode Switching Regulator Onboard 25k Signature Resistor with Disable Programmable Classification Current (Class 0-4) Thermal Overload Protection Power Good Signal Integrated Error Amplifier and Voltage Reference Low Profile 16-Pin SSOP Package APPLICATIO S ■ ■ ■ ■ IP Phone Power Management Wireless Access Points Security Cameras Power over Ethernet , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATIO Class 2 PD with 3.3V Isolated Power Supply + + U U U • • 42671f 1 LTC4267-1 ABSOLUTE (Note 1) AXI U RATI GS VPORTN with Respect to VPORTP Voltage ... 0.3V to –100V POUT, SIGDISA, ⎯P⎯W⎯R⎯G⎯D Voltage..................... VPORTN + 100V to VPORTN – 0.3V PVCC to PGND Voltage (Note 2) Low Impedance Source ........................... –0.3V to 8V Current Fed .......................................... 5mA into PVCC RCLASS Voltage .................VPORTN + 7V to VPORTN – 0.3V ⎯P⎯W⎯R⎯G⎯D Current .....................................................10mA RCLASS Current.....................................................100mA NGATE to PGND Voltage ...........................–0.3V to PVCC VFB, ITH/RUN to PGND Voltages ................ –0.3V to 3.5V SENSE to PGND Voltage .............................. –0.3V to 1V NGATE Peak Output Current (