LTC4355 LINER [Linear Technology], LTC4355 Datasheet
LTC4355
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LTC4355 Summary of contents
Page 1
... N-channel MOSFETs instead of Schottky diodes reduces power consumption, heat dissipation and PC board area. With the LTC4355, power sources can easily be ORed together to increase total system reliability. The LTC4355 can diode-OR two positive supplies or the return paths of two negative supplies, such –48V system. ...
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... For more information on lead free part marking, go to: For more information on tape and reel specifications, go to: Operating Temperature Range LTC4355C ................................................ 0°C to 70°C LTC4355I .............................................–40°C to 85°C Storage Temperature Range DFN Package ......................................–65°C to 125°C SO Package ........................................–65°C to 150°C Lead Temperature (Soldering, 10 sec) – ...
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... Note 2: All currents into pins are positive, all voltages are referenced to GND unless otherwise specified. Note 3: The GATEx pins are internally limited to a minimum of 13V above INx. Driving these pins beyond the clamp may damage the part. LTC4355 MIN TYP MAX ...
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... LTC4355 Typical perForMance characTerisTics OUT OUT 2 OUT IN 1.5 1.0 0 (V) OUT 4355 G01 GATE GATE 15 V > 18V 12V (µA) GATE 4355 G04 FET Turn-Off Time vs GATE Capacitance 500 V < V ...
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... MOSFETs. The voltage sensed at this pin is used to control the source-drain voltages across the MOSFETs and is used by the fault detection circuits that drive the PWRFLT and VDSFLT pins. The LTC4355 is powered from the OUT pin. PWRFLTx (Pins 10,13/12,15): Power Fault Outputs. Open-drain output that pulls to GND when V below 1 ...
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... LTC4355 block DiagraM IN1 VDSFLT FUSEFLT1 PWRFLT1 MON1 GATE1 OUT GATE2 GATE1 GATE2 AMP AMP + + – 25mV 25mV – + – + – SD(FLT) SD(FLT SD1(FLT) SD2(FLT) FAULT FAULT DV = SD(FLT) 0.25V, 0.5V OR 1.5V – – FUSE1 FUSE2 FAULT FAULT + + + + 3.5V 3.5V – – MON1 MON2 ...
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... The drains of the MOSFETs are connected together at the OUT pin, which is the positive supply of the device. The gates of the external MOSFETs are driven by the LTC4355 to regulate the voltage drop across the pass transistors. At power-up, the initial load current flows through the body diode of the MOSFET with the higher INx voltage ...
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... R ). DS(ON) Fault Conditions The LTC4355 monitors fault conditions and shunts current away from LEDs or optocouplers, turning each one off to indicate a specific fault condition (see Table 1). When the voltage drop across the pass transistor is higher than the configurable DV fault threshold, the internal ...
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... The remaining system power supply delivers the load cur- rent through the body diode of its pass transistor until the channel turns on. The LTC4355 ramps the gate up with 20µA, turning on the N-channel MOSFET to reduce the voltage drop across it. ...
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... Layout Considerations The following advice should be considered when laying out a printed circuit board for the LTC4355. 0 The inputs to the servo amplifiers, IN1, IN2, and OUT should be connected as closely as possible to the MOSFETs’ terminals for good accuracy. ...
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... MON2 GND PWRFLT2 GREEN LEDs PANASONIC LN1351C 12k V CC LTC4354 FAULT 1µ IRF3710 IRF3710 Figure 3. –36V to –72V/10A with Positive Supply and Negative Supply Diode-ORing LTC4355 33k 33k 33k LOAD 33k RED LED PANASONIC LN1251CLA 4355 F03 4355fa ...
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... Figure 4. 36V to 72V/10A with Positive Supply and Negative Supply Diode-ORing, Combined Fault Outputs, and Zener Clamps on MOSFET Gates IRLR3110ZPbF 12V ZENER CM4Z669-LTC IRLR3110ZPbF 12V ZENER CM4Z669-LTC IN1 GATE1 IN2 GATE2 OUT VDSFLT FUSEFLT1 LTC4355 FUSEFLT2 PWRFLT1 GND PWRFLT2 12k V CC LTC4354 FAULT 1µF ...
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... GND PWRFLT2 F1 M1 30A IRFS4710 M2 IRFS4710 IN1 IN2 GATE1 GATE2 OUT MON1 VDSFLT FUSEFLT1 LTC4355 SET PWRFLT1 FUSEFLT2 MON2 GND PWRFLT2 LTC4355 TO LOAD 10k 10k 10k GREEN LEDs PANASONIC LN1351C 4355 TA03 TO LOAD R3 R5 33k 33k R4 33k GREEN LEDs ...
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... MEDIUM LONG 7A –48V_A FDS3672 MEDIUM SHORT 7A –48V_B FDS3672 2 C Current and Voltage Monitor FDS3672 91Ω FDS3672 SMBT70A 22nF 100V IN1 GATE1 IN2 GATE2 OUT MON1 LTC4355CS SET MON2 GND 137k 1µ 100nF 100nF 100nF HZS5C1 100k 10.2k D: 1N4148WS 1.1k 1.1k 1.1k 1.1k 1µF ...
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... N .160 ±.005 .228 – .244 (5.791 – 6.197) N .053 – .069 (1.346 – 1.752) 0° – 8° TYP .014 – .019 (0.355 – 0.483) TYP LTC4355 R = 0.115 0.40 ± 0.10 TYP 0.05 TYP 3.30 ±0.10 3.00 ±0.10 (2 SIDES) 1.70 ± 0. 0.25 ± 0.05 0.75 ±0.05 ...
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... Hot Swap is a trademark of Linear Technology Corporation. Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 200W AdvancedTCA Ideal Diode-OR 10A FDS3672 10A FDS3672 IN1 GATE1 IN2 GATE2 OUT LTC4355 GND 12k V CC LTC4354 FDS3672 7A ...