LTC4271IUF#PBF Linear Technology, LTC4271IUF#PBF Datasheet
LTC4271IUF#PBF
Specifications of LTC4271IUF#PBF
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LTC4271IUF#PBF Summary of contents
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... The LTC4270/LTC4271 is available in multiple power grades allowing delivered PD power up to 90W. 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 property of their respective owners. XIO0 XIO1 0.22μ ...
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LTC4270/LTC4271 ABSOLUTE MAXIMUM RATINGS LTC4270 (Note 1, Note 4) Supply Voltages AGND – V ........................................... –0.3V to 80V EE VSSK (Note 7) ..................... V EE Digital Pins XIOn ................................. V – 0.3V to CAP2 + 0.3V EE Analog Pins SENSEn, ...
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... T = 40°C/W JMAX JA EXPOSED PAD (PIN 53) IS VSSK, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC4271IUF#PBF LTC4271IUF#TRPBF LTC4270AIUKG#PBF LTC4270AIUKG#TRPBF LTC4270BIUKG#PBF LTC4270BIUKG#TRPBF LTC4270CIUKG#PBF LTC4270CIUKG#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. ...
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LTC4270/LTC4271 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Main PoE Supply Voltage EE Undervoltage Lock-Out V V Supply Voltage DD DD Undervoltage Lock-Out V Internal Regulator Supply Voltage CAP1 V Internal Regulator Supply Voltage CAP2 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Overcurrent Sense Voltage CUT Overcurrent Sense in AUTO Pin Mode V Active Current Limit in 802.3af Compliant Mode LIM Active Current Limit in High Power Mode Active Current ...
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LTC4270/LTC4271 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER XIO V XIO Digital Output Low OLX V XIO Digital Output High OHX XIO Digital Input Low Voltage XIO Digital Input High Voltage Internal Pull ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER Timing f Clock Frequency SCLK t Bus Free Time 1 t Start Hold Time 2 t SCL Low Time 3 t SCL High Time 4 t ...
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LTC4270/LTC4271 TYPICAL PERFORMANCE CHARACTERISTICS 802.3af Power On Sequence in AUTO Pin Mode 0 AGND –10 FORCED CURRENT –20 DETECTION FORCED VOLTAGE –30 DETECTION VEE = –55V 802.3af –40 CLASS 3 PD CLASSIFICATION POWER ON –50 VEE –60 50ms/DIV 42701 G01 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 802.3at I Threshold LIM vs Temperature 220 PORT 1 REG 48h = C0h R = 0.25Ω SENSE 216 212 208 204 –40 – TEMPERATURE (°C) DC Disconnect Threshold vs Temperature 2.50 PORT 1 REG ...
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LTC4270/LTC4271 TEST TIMING DIAGRAMS V PORTn V INT Figure 1. Detect, Class and Turn-On Timing in AUTO Pin or Semi-auto Modes 10 t CLASSIFICATION DET FORCED- FORCED-CURRENT VOLTAGE MARK V CLASS t CLE t CLE ...
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TEST TIMING DIAGRAMS SCL t 2 SDA GATEn t MSD MSD 42701 F04 Figure 4. Shut Down Delay Timing Figure 5. I ...
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LTC4270/LTC4271 TIMING DIAGRAMS SCL SDA AD3 AD2 AD1 AD0 AD6 1 0 START BY MASTER FRAME 1 SERIAL BUS ADDRESS BYTE SCL SDA AD3 AD2 AD1 AD0 R/W ACK A7 AD6 1 0 START BY ACK BY ...
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I C TIMING DIAGRAMS SCL SDA AD6 START BY MASTER SCL SDA 0 START BY MASTER 1 0 AD3 AD2 AD1 AD0 R/W ACK ACK BY SLAVE FRAME 1 FRAME 2 SERIAL BUS ADDRESS ...
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LTC4270/LTC4271 PIN FUNCTIONS LTC4270 SENSEn (Pins 11, 15, 18, 21, 24, 30, 33, 37, 40): Port n Current Sense Input. SENSEn monitors the external MOSFET current via a 0.5Ω or 0.25Ω sense resistor between SENSEn and V ...
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PIN FUNCTIONS CPD (Pin 8): Clock Transceiver Positive Input Output (Digital). Connect to CPA through a data transformer. CND (Pin 9): Clock Transceiver Negative Input Output (Digital). Connect to CNA through a data transformer. DPD (Pin 10): Data Transceiver Positive ...
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LTC4270/LTC4271 APPLICATIONS INFORMATION OVERVIEW Power over Ethernet, or PoE standard protocol for sending DC power over copper Ethernet data wiring. The IEEE group that administers the 802.3 Ethernet data stan- dards added PoE powering capability in 2003. This ...
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... PD power levels. The A-grade LTC4270/LTC4271 chipset extends PoE power delivery capabilities to LTPoE ++ levels. LTPoE ++ is a Linear Technology proprietary specification allowing for the delivery 90W to LTPoE ++ compliant PDs. The LTPoE ++ architecture extends the IEEE physical power negotiation to include 35W, 45W, 70W and 90W power levels ...
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LTC4270/LTC4271 APPLICATIONS INFORMATION Extended Power LTPoE ++ A-grade LTC4270/LTC4271 parts add the capability to autonomously deliver up to 90W of power to the PD. LTPoE ++ PDs may forgoe 802.3 LLDP support and rely solely on the LTPoE ++ Physical ...
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APPLICATIONS INFORMATION Reset and the AUTO/MID Pins The initial LTC4270/LTC4271 configuration depends on the state of the AUTO and MID pins during reset. Reset occurs at power-up, or whenever the RESET pin is pulled low or the global Reset All ...
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LTC4270/LTC4271 APPLICATIONS INFORMATION 275 25kΩ SLOPE 165 SECOND DETECTION POINT VALID PD 0V-2V VOLTAGE OFFSET Figure 12. PD Detection Table 4. Detection Status MEASURED PD SIGNATURE DETECTION RESULT Incomplete or Not Yet Tested Detect Status Unknown < 2.4k Short Circuit ...
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APPLICATIONS INFORMATION the classification signature current (in this case, Class 3) in the V range. Table 4 shows the possible clas- CLASS sification values. Table 4. 802.3af and 802.3at Classification Values CLASS RESULT Class 0 No Class Signature Present; Treat ...
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LTC4270/LTC4271 APPLICATIONS INFORMATION the Port Status register will always report the results of the last class pulse invalid Class 4–Class 2 combination would report a second class pulse was run in the High Power Status register (which implies ...
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APPLICATIONS INFORMATION Table 5. Example Current Limit Settings INTERNAL REGISTER SETTING (hex) I (mA 0.5Ω LIM SENSE 53 88 106 08 159 89 213 80 266 8A 319 09 372 8B 425 00 478 8E 531 92 584 ...
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... LTC4271 firmware is field-upgradable by downloading and executing RAM images. RAM images are volatile and must be re-downloaded after each V but will remain valid during reset and V Contact Linear Technology for code download procedures and RAM images. Readback EE voltage with an internal 12-bit A/D converter. ...
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APPLICATIONS INFORMATION SERIAL DIGITAL INTERFACE Overview The LTC4270/LTC4271 communicates with the host us- 2 ing a standard SMBus/I C 2-wire interface. The LTC4270/ LTC4271 is a slave-only device, and communicates with the host master using the standard SMBus protocols. Interrupts ...
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LTC4270/LTC4271 APPLICATIONS INFORMATION For simple devices such as small PoE switches, the isola- tion requirement can be met by using an isolated main power supply for the entire device. This strategy can be used if the device has no electrically ...
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APPLICATIONS INFORMATION 3.3V 0.1μF V DD33 GP0 GP1 NO ISOLATION MID REQUIRED ON 2 RESET I C INTERFACE MSD AUTO INT LTC4271 SCL SDAIN SDAOUT AD0 AD1 AD2 AD3 AD6 DGND CAP1 1μF External MOSFET Careful selection of the power ...
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LTC4270/LTC4271 APPLICATIONS INFORMATION ESD/Cable Discharge Protection Ethernet ports can be subject to significant ESD events when long data cables, each potentially charged to thou- sands of volts, are plugged into the low impedance of the RJ45 jack. To protect against ...
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TYPICAL APPLICATION LTC4270/LTC4271 42701f 29 ...
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LTC4270/LTC4271 PACKAGE DESCRIPTION 4.50 0.05 2.45 0.05 (4 SIDES) 3.10 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 4.00 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING PROPOSED TO BE MADE A JEDEC PACKAGE OUTLINE MO-220 VARIATION ...
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... ALL DIMENSIONS ARE IN MILLIMETERS Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. UKG Package 52-Lead Plastic QFN (7mm × ...
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... RJ45 CONNECTOR FDMC3612 1 RJ45 2 S1B 0.01μF CONNECTOR 3 200V 0.01μF 0.01μ 200V 200V 6 75Ω 75Ω 0.01μF 7 200V 8 0.01μF 0.01μF 200V 200V 75Ω 75Ω 42701 F16 LT 0411 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2011 42701f ...