LTC4280IUFD#TR Linear Technology, LTC4280IUFD#TR Datasheet
LTC4280IUFD#TR
Specifications of LTC4280IUFD#TR
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LTC4280IUFD#TR Summary of contents
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... Electronic Circuit Breakers n Computers, Servers n Platform Management L, LT, LTC, LTM, Linear Technology, the Linear logo and Hot Swap are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION 12V Application with 5A Circuit Breaker 12V 34.8k 0.1μ ...
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... LTC4280CUFD LTC4280CUFD#TR LTC4280IUFD LTC4280IUFD#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Supplies V Input Supply Range DD V Input Supply Overvoltage Threshold OV(VDD) I Input Supply Current DD V Input Supply Undervoltage Lockout DD(UVL) V Input Supply Undervoltage Lockout ...
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LTC4280 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Other Pin Functions V GPIO Pin Output Low Voltage GPIO(OL) I GPIO Pin Input Leakage Current GPIO(OH) I SOURCE Pin Input Current SOURCE Input (ON, OV, UV, ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Interface V ADR0, ADR1, ADR2 Input High Voltage ADR(H) I ADR0, ADR1, ADR2 Hi-Z Input Current ADR(IN,Z) V ADR0, ADR1, ADR2 Input Low Voltage ADR(L) ...
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LTC4280 TYPICAL PERFORMANCE CHARACTERISTICS (V) DD 4280 G01 V vs Temperature TH(UV) 1.240 1.238 1.236 1.234 1.232 1.230 –50 – ...
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TYPICAL PERFORMANCE CHARACTERISTICS ΔV vs Temperature GATE 6 6 12V DD 5.9 5.8 5 3.3V DD 5.6 5.5 5.4 –50 – TEMPERATURE (°C) 4280 G10 ...
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LTC4280 PIN FUNCTIONS ADIN: ADC Input. A voltage between 0V and 1.235V applied to this pin is measured by the onboard ADC. Tie to ground if unused. ADR0, ADR1, ADR2: Serial Bus Address Inputs. Tying these pins to ground, to ...
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PIN FUNCTIONS SCL: Serial Bus Clock Input. Data at the SDA pin is shifted in or out on rising edges of SCL. This is a high impedance pin that is generally driven by an open-collector output from a master controller. ...
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LTC4280 FUNCTIONAL DIAGRAM 1.235V UV – RST + 0.4V – OV OV1 + INTV CC – 1.235V 10μ 1.235V EN – – 1.235V UVLO1 + 2.84V V DD – OV2 + – ...
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TIMING DIAGRAM SDAI/SDAO SCL t HD, STA START CONDITION SU, DAT SU, STA HD, DATO HD, STA HD, DATI REPEATED START CONDITION LTC4280 BUF t SU, STO t SP 4280 TD01 STOP ...
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LTC4280 OPERATION The LTC4280 is designed to turn a board’s supply voltage on and off in a controlled manner, allowing the board to be safely inserted or removed from a live backplane. During normal operation, the charge pump and gate ...
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APPLICATIONS INFORMATION A typical LTC4280 application high availability system in which a positive voltage supply is distributed to power individual cards. The device measures card voltages and currents and records past and present fault conditions. The system ...
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LTC4280 APPLICATIONS INFORMATION When the MOSFET is turning on, the inrush current follows the foldback profi shown in Figure 2. Meanwhile the FILTER pin is held low with 0.6mA to prevent the FILTER pin from generating an overcurrent ...
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APPLICATIONS INFORMATION Overcurrent Fault The LTC4280 features an adjustable current limit that protects against short-circuits or excessive load current until an overcurrent fault is generated. An overcurrent fault can occur in two different manners. First, at the end of start-up ...
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LTC4280 APPLICATIONS INFORMATION If the system shuts down due to a fault, it may be desirable to restart the system simply by removing and reinserting a load card. In cases where the LTC4280 and the switch reside on a backplane ...
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APPLICATIONS INFORMATION pin or bit A3 going from high to low, if the UV pin is brought below its 0.4V reset threshold for 2μ INTV below its 2.64V undervoltage lockout threshold. Finally, when EN is brought from high ...
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LTC4280 APPLICATIONS INFORMATION of R5 resistance, the absence of a drain bypass capacitor, a combination of bus wiring inductance and bus supply output impedance. To prevent this second type of oscillation avoid load capacitance below 10μF, alternately connect an external ...
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APPLICATIONS INFORMATION For a start-up time of 4ms with a 2x safety margin we choose: t STARTUP C 2 • = TIMER μ ≅ μF = TIMER 12 3 ...
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LTC4280 APPLICATIONS INFORMATION SDA SCL START ADDRESS CONDITION Digital Interface The LTC4280 communicates with a bus master using a 2 2-wire interface compatible with extension for low power devices. ...
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APPLICATIONS INFORMATION remains LOW during this pulse to acknowledge receipt of the data. If the slave fails to acknowledge by leaving SDA high, then the master may abort the transmission by generating a STOP condition. When the master is receiving ...
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LTC4280 APPLICATIONS INFORMATION ADDRESS 1 0 a4:a0 Figure 10. LTC4280 Serial Bus SDA Read Word Protocol Figure 11. LTC4280 Serial Bus SDA Alert Response Protocol ADDRESS A COMMAND A DATA 1 0 a4:a0 0 ...
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APPLICATIONS INFORMATION Table 1. LTC4280 Device Addressing (UH24 Package) DEVICE DESCRIPTION ADDRESS h 7 Mass Write BE 1 Alert Response ...
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LTC4280 APPLICATIONS INFORMATION Table 2. CONTROL Register A (00h)—Read/Write BIT NAME OPERATION A7:6 GPIO Confi gure FUNCTION Power Good (Default) Power Good General Purpose Output General Purpose Input A5 Test Mode Enable Enables Test Mode to Disable the ADC; 1 ...
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APPLICATIONS INFORMATION Table 4. STATUS Register C (02h)—Read BIT NAME OPERATION C7 FET FET On FET Off C6 GPIO Input State of the GPIO Pin GPIO High GPIO Low C5 FET ...
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LTC4280 TYPICAL APPLICATIONS 5V Backplane Resident Application with Insertion Activated Turn-On and a 5A Circuit Breaker 11. 1.74k 0.1μ 2.67k 0.005Ω FDD3706 R5 10Ω + ...
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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. UFD Package 24-Lead Plastic QFN (4mm × ...
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... Si7880DP R5 10Ω 22nF 15k R7 –12V 30.1k – SENSE GATE SOURCE ADIN 3.57k GPIO LTC4280UFD 1% EN FILTER ADR1 ADR2 GND TIMER TIMER 1μF 47nF 4280 F14 LT 0510 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 OUTPUT C L 1000μF –12V 4280f ...