LTC4290/LTC4271 + ++ 8-Port PoE/PoE /LTPoE PSE Controller FEATURES DESCRIPTION n Eight Independent PSE Channels The LTC 4290/LTC4271 chipset is an 8-port power sourc- n Compliant with IEEE 802.3at Type 1 and 2 ing equipment (PSE) controller designed for use in IEEE n Chipset Provides Electrical Isolation 802.3at Type 1 and Type 2 (high power) compliant Power n Reduced BOM Cost over Ethernet (PoE) systems. Transformer-isolated com- n Eliminates up to 6 High Speed Opto-Couplers munication protocol replaces expensive opto-couplers n Eliminates Isolated 3.3V Power Supply and complex isolated 3.3V supply resulting in significant n Low Power Dissipation BOM cost savings. The LTC4290/LTC4271 chipset delivers n 0.25 Sense Resistance Per Channel lowest-in-industry heat dissipation by utilizing low-R DS(ON) n Very High Reliability 4-Point PD Detection external MOSFETs and 0.25 sense resistors. n 2-Point Forced Voltage Advanced power management features include per-port n 2-Point Forced Current 12-bit current monitoring ADCs, DAC-programmable cur- n V and V Monitoring EE PORT rent limit, and versatile fast shut-down of preselected ports. n 1 Second Rolling I Averaging PORT Advanced power management host software is available n Supports 2-Pair and 4-Pair Output Power under a no-cost license. PD discovery uses a proprietary 2 n 1MHz I C Compatible Serial Control Interface dual-mode 4-point detection mechanism ensuring excel- n Available In Three Power Grades lent immunity from false PD detection. Midspan PSEs n ++ A-Grade LTPoE 38.7W to 90W are supported with 2-event classification and a 2 second n + B-Grade PoE 25.5W 2 backoff timer. The LTC4290/LTC4271 includes an I C n C-Grade PoE 13W serial interface operable up to 1MHz. n Available In a 40-Lead 6mm 6mm (LTC4290) and The LTC4290/LTC4271 is available in multiple power 24-Lead 4mm 4mm (LTC4271) QFN Package grades allowing delivered PD power up to 90W. APPLICATIONS L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks ++ and LTPoE is a trademark of Linear Technology Corporation. All other trademarks are the n PoE PSE Switches/Routers property of their respective owners. n PoE PSE Midspans TYPICAL APPLICATION 3.3V 0.1F XIO0 XIO1 GP0 V 0.22F DD33 S1B LTC4290/LTC4271 FAMILY 100V GP1 NO ISOLATION OUTn CPD CPA PORTn MID REQUIRED ON MAX 2 100 100 I C INTERFACE RESET LTC4290 DELIVERED GATEn S1B MSD 3.3V 54V ++ + AUTO GRADE ISOLATION LTPoE PoE PoE POWER 0.25 100 100 INT SENSEn 54V CND CNA l l l A Transformer 90W LTC4271 LTC4290 SCL 0.22F DPD DPA SDAIN l l B Transformer 25.5W 100V S1B SDAOUT 100 100 OUT1 PORT1 l C Transformer 13W 3.3V 54V AD0 AD1 100 100 S1B GATE1 AD2 0.25 DND DNA AD3 SENSE1 54V 10 AD6 AGND CAP2 V VSSK DGND CAP1 EE 1F 0.1F + >47F 2nF 2kV 1F SYSTEM BULK CAP 54V 54V 429071 TA01a 429071fb 1 For more information www.linear.com/LTC4290LTC4290/LTC4271 ABSOLUTE MAXIMUM RATINGS (Notes 1, 4) (Note 1) LTC4290 LTC4271 Supply Voltages Supply Voltages AGND V ........................................... 0.3V to 80V V DGND ......................................... 0.3V to 3.6V EE DD VSSK (Note 7) ..................... V 0.3V to V + 0.3V Digital Pins EE EE Digital Pins SCL, SDAIN, SDAOUT, INT, RESET, MSD, ADn, AUTO, XIOn ................................. V 0.3V to CAP2 + 0.3V MID, GPn ........................DGND 0.3V to V + 0.3V EE DD Analog Pins Analog Pins SENSEn, GATEn, OUTn ........ V 0.3V to V + 80V CAP1 (Note 13) ...........................0.3V to DGND + 2V EE EE CAP2 (Note 13) ....................... V 0.3V to V + 5V CPD, CND, DPD, DND ......DGND 0.3V to V + 0.3V EE EE DD CPA, CNA, DPA, DNA ..............V 0.3V to V + 0.3 Operating Ambient Temperature Range EE EE Operating Ambient Temperature Range LTC4271I..............................................40C to 85C LTC4290I .............................................40C to 85C Junction Temperature (Note 2) ............................ 125C Junction Temperature (Note 2) ............................ 125C Storage Temperature Range .................. 65C to 150C Storage Temperature Range .................. 65C to 150C 429071fb 2 For more information www.linear.com/LTC4290