LTC4265IDE#PBF Linear Technology, LTC4265IDE#PBF Datasheet
LTC4265IDE#PBF
Specifications of LTC4265IDE#PBF
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LTC4265IDE#PBF Summary of contents
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... The LTC4265 is available in the space-saving low profi le (4mm × 3mm) DFN package and is drop-in compatible with the LTC4264. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. LTC4265 ...
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... LEAD FREE FINISH TAPE AND REEL LTC4265CDE#PBF LTC4265CDE#TRPBF LTC4265IDE#PBF LTC4265IDE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Operating Input Voltage Signature Range Classifi cation Range Turn-On Voltage Undervoltage Lock Out Overvoltage Lock Out ON/UVLO Hysteresis Window Signature/Class Hysteresis Window Reset Threshold SUPPLY CURRENT Supply Current at ...
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LTC4265 TYPICAL PERFORMANCE CHARACTERISTICS Input Current vs Input Voltage 25k Detection Range 0 25°C A 0.4 0.3 0.2 0 GND VOLTAGE (V) 4265 G01 Signature Resistance vs Input Voltage ...
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PIN FUNCTIONS SHDN (Pin 1): Shutdown Input. Use this pin for auxiliary power application. Drive SHDN high to disable LTC4265 operation and corrupt the signature resistance. If unused, tie SHDN T2PSE (Pin 2): Type-2 PSE Indicator, ...
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LTC4265 APPLICATIONS INFORMATION OVERVIEW Power over Ethernet (PoE) continues to gain popularity as more products are taking advantage of having DC power and high speed data available from a single RJ45 connector. As PoE continues to grow in the marketplace, ...
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APPLICATIONS INFORMATION These modes satisfy the requirements defi ned in the IEEE 802.3af/at specifi cation. Table 1. LTC4265 Modes of Operation as a Function of Input Voltage GND (V) LTC4265 MODES OF OPERATION 0V to 1.4V Inactive (Reset After 1st ...
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LTC4265 APPLICATIONS INFORMATION SIGNATURE CORRUPT OPTION In some designs that include an auxiliary power option necessary to prevent a PD from being detected by a PSE. The LTC4265 signature resistance can be corrupted with the SHDN pin (Figure ...
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APPLICATIONS INFORMATION In 2-event classifi cation, a Type-2 PSE probes for power classifi cation twice. Figure 4 presents an example of a 2-event classifi cation. The 1st classifi cation event occurs when the PSE presents an input voltage between 14.5V ...
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LTC4265 APPLICATIONS INFORMATION PD STABILITY DURING CLASSIFICATION Classifi cation presents a challenging stability problem due to the wide range of possible classifi cation load current. The onset of the classifi cation load current introduces a voltage drop across the cable ...
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APPLICATIONS INFORMATION Once C1 is fully charged, the LTC4265 turns on is internal MOSFET and passes power to the PD load. The LTC4265 continues to power the PD load as long as the input volt- age does not fall below ...
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LTC4265 APPLICATIONS INFORMATION OVERVOLTAGE LOCKOUT The LTC4265 includes an overvoltage lockout (OVLO) feature (Figure 5) which protects the LTC4265 and its load from an overvoltage event. If the input voltage exceeds the OVLO threshold, the LTC4265 discontinues PD operation. Normal ...
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APPLICATIONS INFORMATION Bel Fuse, Coilcraft, Halo, Pulse, and Tyco (Table 4) can assist in selecting an appropriate isolation transformer and proper termination methods. Table 4. Power-over-Ethernet Transformer Vendors VENDOR CONTACT INFORMATION Bel Fuse Inc. 206 Van Vorst Street Jersey City, ...
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LTC4265 APPLICATIONS INFORMATION Input Capacitor The IEEE 802.3af/at standard includes an impedance requirement in order to implement the AC disconnect function. A 0.1μF capacitor (C14 in Figure 7) is used to meet this AC impedance requirement. Transient Voltage Suppressor The ...
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APPLICATIONS INFORMATION ACTIVE-HIGH ENABLE GND PD LTC4265 TO LOAD PSE RUN PWRGD –54V OUT ACTIVE-LOW ENABLE R9 GND 100k R TO LTC4265 S 10k PSE PWRGD D9 5.1V MMBZ5231B –54V OUT ACTIVE-LOW ENABLE R10 ...
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... PoE power is already present. This confi guration also provides a seamless transition from PoE to auxiliary power when auxiliary power is applied, however, the removal of auxiliary power to PoE power is not seamless. Contact Linear Technology applications support for detail information on implementing a custom auxiliary power supply. TVS ...
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APPLICATIONS INFORMATION IEEE 802.3at SYSTEM POWER-UP REQUIREMENT Under the IEEE 802.3at standard must operate under 12.95 Watts in accordance with IEEE 802.3af standards until it recognizes a Type-2 PSE. Initializing PD operation in 12.95-Watt mode eliminates interoperability issue ...
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LTC4265 APPLICATIONS INFORMATION 18 (V) OUTPUT (%) EFFICIENCY 4265fa ...
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... ON THE TOP AND BOTTOM OF PACKAGE 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. DE/UE Package 12-Lead Plastic DFN (4mm × ...
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... Current Limit LTC4267 IEEE 802.3af PD Interface with Integrated Switching LTC4267-1 Regulator LTC4267-3 LTC4268-1 High Power PD with Synchronous No Opto Flyback Controller ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 1mH DO1608C-105 ...