LTC4263-1 Linear Technology, LTC4263-1 Datasheet
LTC4263-1
Related parts for LTC4263-1
LTC4263-1 Summary of contents
Page 1
... An LED pin indi- cates the state of the port and detection backoff timing is confi gurable for either endpoint or midspan operation. The LTC4263-1 is available in a miniature 14-pin 4mm × 3mm DFN package. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ...
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... LTC4263-1 www.DataSheet4U.com ABSOLUTE MAXIMUM RATINGS (Note 1, Note 2) Supply Voltages V – V ........................................... 0.3V to –80V SS DD48 V ........................................V DD5 Pin Voltages and Currents LEGACY, MIDSPAN, SD, OSC ..V LED .......................................V OUT, ACOUT ............................................ (See Note 3) Operating Ambient Temperature Range LTC4263CDE-1 ............................................ 0°C to 70°C LTC4263IDE-1 ......................................... –40°C to 85°C Junction Temperature (Note 4) ............................. 125°C Storage Temperature Range ................... – ...
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... ACOUT SS V – OSC SS V – Port On OSC 10mA LED MIDSPAN, SD LEGACY MIDSPAN, SD LEGACY 0V ≤ (V – ≤ 5V LEGACY SS LTC4263-1 not driven externally. All voltages are MIN TYP MAX 1 360 500 640 l 540 570 600 l 615 645 ...
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... Note 2: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to V specifi ed. Note 3: 80mA of current may be pulled from the OUT or ACOUT pin without damage whether the LTC4263-1 is powered or not. These pins will also withstand a positive voltage 80V. SS Note 4: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions ...
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... I t OUT OVLD 300mA/DIV LOAD 0mA APPLIED 42631 G11 10ms/DIV I = CURRENT IN PORT 1Ω RESISTOR APPLIED TO OUTPUT OF CIRCUIT ON FRONT PAGE 300mA/DIV 42631 G14 1μs/DIV LTC4263-1 Overload Restart Delay V DD48 OUT 10V/DIV LOAD FULLY CHARGED PORT 1A/DIV 500ms/DIV 42631 G02 ...
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... LTC4263-1 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS Current Limit and Foldback 675 600 525 450 375 300 225 150 – V (V) DD48 OUT I DC Supply Current vs DD48 Supply Voltage with V 1 25°C A 1.0 0.8 0.6 0.4 0 Temperature ON 2.0 1.8 1.6 1.4 1.2 1.0 –40 –20 0 TEMPERATURE (° ...
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... DD48 t DET V OUT t DETDLY DC Disconnect Timing I I OUT MIN V DD48 V OUT MPS PORT TURN-ON t PON 42631 TT01 t MPDO 42631 TT03 LTC4263-1 Current Limit Timing I LIM I CUT I OUT t OVLD V DD48 V OUT V 42631 TT02 SS AC Disconnect Timing V OSC V DD48 V OUT ACDMIN ...
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... See Applications , only IEEE 802.3af SS Information section for more information. SD (Pin 12): Shutdown. If held low, the LTC4263-1 is prevented from performing detection or powering the port. Pulling SD low will turn off the port powered. When released, a 4-second delay will occur before detection is attempted ...
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... V SS 0.1μF 7 OSC BOLD LINES INDICATE HIGH CURRENT Hot Swap IS A TRADEMARK OF LINEAR TECHNOLOGY CORPORATION V DD48 11 5V REG INT5 EXT5 V DD5 3 500k CONTROL I DET Hot Swap TM LTC4263 0.1μF 2 LEGACY 3 MIDSPAN TO PORT MAGNETICS SMAJ58A 500k 9 10 OUT 0.47μ ACOUT 42631 BD ...
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... RFID readers. With proper system design, proprietary high power PoE solutions using the LTC4263-1 can deliver 25W (min high power 2-pair PD at the end of a 100 meter CAT5 cable and 50W (min) using a 4-pair solution. ...
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... This result is stored and the second current is applied to the port, allowed to settle and the voltage measured. The LTC4263-1 will not power the port if the PD has more than 5μF in parallel with its signature resistor unless legacy mode is enabled. ...
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... LIM ever current greater than I 42631 F07 the current is still above I the LTC4263-1 will turn off power to the port and fl ash the LED. In this situation, the LTC4263-1 waits four seconds and then restarts detection. If the overload condition is removed before the t powered and the timer is reset ...
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... LTC4263-1. At port turn-on, while I is active, the instantaneous power dissipated by the LIM LTC4263-1 can be as high as 18W. This can cause 40ºC or more of die heating in a single turn-on sequence. Similarly, excessive heating can occur if an attached PD repeatedly pushes the LTC4263-1 into I LIM current ...
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... The LTC4263-1 may be reset by pulling the SD pin low. The port is turned off immediately and the LTC4263-1 sits idle. After SD is released there will be a 4-second delay before the next detection cycle begins ...
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... IEEE 802.3af committee has chosen 57V as a nominal maximum. In this example, a 56±1V power supply output sets the lower limit to 55V. The LTC4263-1 overload current limit monitors port current and removes LTC4263-1 ...
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... P LOSS_4263-1(MAX) = (540mA) = 0.9W (MAX) Figure 8. Example of Power Delivery Calculation Using the LTC4263-1 power if the port exceeds 540mA(min). This sets the maximum system operating current and along with the working voltage, limits the power available to the PD. The power at the PSE output is reduced by the resistance of ...
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... The LTC4263-1 has a high speed fault current limit circuit that shuts down the port in 20μs (typ). In this case, there is lower inductance but higher current so the event is still severe ...
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... AC power distribution boundary. In this case, electrical supply DD5 isolation must be maintained between each port in the PSE. The LTC4263-1 can be used to build a multi-port Environment B PSE by powering each LTC4263-1 from a separate, isolated 56V supply. In all PSE applications, there should be no user accessible connections to the LTC4263-1 other than the RJ-45 port ...
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... Plastic DFN (4mm × 3mm) (Reference LTC DWG # 05-08-1708 Rev B) 0.70 ±0.05 3.30 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 3.00 REF 4.00 ±0.10 (2 SIDES 0.05 TYP 3.00 ±0.10 (2 SIDES) 0.75 ±0.05 0.00 – 0.05 LTC4263 0.115 0.40 ± 0.10 TYP 8 14 3.30 ±0.10 1.70 ± 0.10 PIN 1 NOTCH R = 0.20 OR 0.35 45° CHAMFER (DE14) DFN 0806 REV 0.25 ± 0.05 0.50 BSC 3.00 REF BOTTOM VIEW— ...
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... LTC4263-1 www.DataSheet4U.com TYPICAL APPLICATION + C3 ISOLATED 0.1μF 56V 100V – LTC4263 DD48 DD5 LED 0.1μF OSC LEGACY 3 MIDSPAN ACOUT OUT SS CMLSHO5 OUT L1: COILCRAFT DS1608C-106 L2: COILCRAFT ETH1-230LD RELATED PARTS PART NUMBER ...