LTC4264CDE#TRPBF Linear Technology, LTC4264CDE#TRPBF Datasheet
LTC4264CDE#TRPBF
Specifications of LTC4264CDE#TRPBF
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LTC4264CDE#TRPBF Summary of contents
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... PD applications. The LTC4264 is available in the space-saving low profi le (4mm × 3mm) DFN package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. LTC4264 V ...
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LTC4264 ABSOLUTE MAXIMUM RATINGS (Notes Voltage ................................................. 0.3V to –90V IN V Voltage ......... V + 90V (and ≤ GND OUT IN SHDN Voltage ............................ Voltage ............... V CLASS LIM_EN PWRGD ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER V I Low Level Input Voltage IL_ILIM LIM_EN V Active Low Power Good PWRGD_OUT Output Low Voltage I Active Low Power Good Leakage PWRGD_LEAK V Active High Power ...
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LTC4264 TYPICAL PERFORMANCE CHARACTERISTICS Input Current vs Input Voltage 25k Detection Range 0 25°C A 0.4 0.3 0.2 0 –2 –4 –6 –8 INPUT VOLTAGE (V) 4264 G01 Signature Resistance vs Input Voltage 28 ∆V V2 ...
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PIN FUNCTIONS SHDN (Pin 1): Shutdown Input. Used to command the LTC4264 to present an invalid signature. Connecting SHDN to GND lowers the signature resistance to an invalid value and disables other LTC4264 operations. If unused, tie SHDN to V ...
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LTC4264 BLOCK DIAGRAM SHDN CLASS I 4 LIM_EN CLASSIFICATION CURRENT LOAD + 1.237V 16k – CONTROL CIRCUITS INPUT CURRENT LIMIT 1400mA + 750mA 300mA – BOLD LINE INDICATES ...
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... LTC4264 to allow quick implementation of a custom system. Alter- nately, the system vendor can choose to build their own high power PSE. Linear Technology provides complete application information for high power PSE solutions delivering up to 35W for 2-pair systems and as much as 70W when used in 4-pair systems ...
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LTC4264 APPLICATIONS INFORMATION PSE GND 0.1µF 0.1µF DGND BYP AGND 3.3V V DETECT DD AUTO CMPD3003 1k 1/4 LTC4259A 0.47µF V SENSE GATE OUT EE 10k S1B 0.25Ω –54V IRLR3410 GND 0.1µF AGND DETECT CMPD3003 1k 1/4 LTC4259A 0.47µF V ...
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APPLICATIONS INFORMATION DETECTION V1 DETECTION V2 CLASSIFICATION –10 –20 UVLO –30 TURN-ON –40 –50 –10 UVLO UVLO –20 OFF ON –30 – LIMIT_LOW = dt C1 –50 –10 POWER POWER –20 BAD GOOD –30 –40 –50 20 POWER ...
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LTC4264 APPLICATIONS INFORMATION RJ45 POWERED 6 DEVICE (PD) INTERFACE AS DEFINED 4 BY IEEE 802.3af Figure 4. PD Front End Using Diode Bridges on Main and Spare Inputs pin high will reduce the signature ...
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APPLICATIONS INFORMATION During classifi cation, the PSE presents a fi xed voltage between –15.5V and –20.5V to the PD (Figure 6). With the input voltage in this range, the LTC4264 asserts a load current from the GND pin through the ...
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LTC4264 APPLICATIONS INFORMATION UNDERVOLTAGE LOCKOUT The IEEE 802.3af specifi cation dictates a maximum turn- on voltage of 42V and a minimum turn-off voltage of 30V for the PD. In addition, the PD must maintain large on-off hysteresis to prevent current-resistance ...
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APPLICATIONS INFORMATION During the inrush event being charged, a large amount of power is dissipated in the MOSFET. The LTC4264 is designed to accept this load and is thermally protected to avoid damage to the onboard power ...
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LTC4264 APPLICATIONS INFORMATION The active high PWRGD pin features an internal, open- collector output referenced to V OUT active high PWRGD pin pulls low until the load capacitor is fully charged. At that point, PWRGD becomes high impedance, indicating the ...
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APPLICATIONS INFORMATION thermal shutdown. For DC loads the maximum ambient temperature can be calculated as: = 125 – θ T • PWR (°C) MAX JA where T is the maximum ambient operating tempera- MAX ture, θ is the junction-to-ambient thermal ...
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LTC4264 APPLICATIONS INFORMATION Diode Bridge IEEE 802.3af allows power wiring in either of two confi gu- rations on the TX/RX wires, and power can be applied to the PD via the spare wire pair in the RJ45 connector. The PD ...
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APPLICATIONS INFORMATION OPTION 1: AUXILIARY POWER INSERTED BEFORE LTC4264 RJ45 + – PHY RX 3 – SPARE – SPARE 8 + ISOLATED WALL V WW TRANSFORMER – ...
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LTC4264 APPLICATIONS INFORMATION will be drawn from the PSE. On the other hand, if the adapter voltage is lower, the PSE will continue to supply power to the PD and the adapter will not be used. Proper operation will occur ...
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APPLICATIONS INFORMATION R from Table unique load current is required, CLASS the value of R can be calculated as: CLASS R = 1.237V/(I – I CLASS LOAD IN_CLASS I is the LTC4264 IC supply current during clas- ...
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LTC4264 APPLICATIONS INFORMATION Shutdown Interface To disable the 25k signature resistor, connect SHDN to the GND pin. Alternately, the SHDN pin can be driven high with respect Examples of interface circuits IN that disable the signature and ...
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APPLICATIONS INFORMATION avoid the possibility of leakage shutting down the OUT LTC4264. If not used, tie SHDN to V The load capacitor connected between GND and V of the LTC4264 can store signifi cant energy when fully ...
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LTC4264 APPLICATIONS INFORMATION 22 4264f ...
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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 Package 12-Lead Plastic DFN (4mm × ...
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... Single IEEE 802.3af Power over Ethernet Controller LTC4263-1 High Power Single PSE Controller LTC4267 IEEE 802.3af PD Interface with an Integrated Switching Regulator Burst Mode is a registered trademark of Linear Technology Corporation Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 ● (408) 432-1900 FAX: (408) 434-0507 ...