LTC1644CGN#PBF Linear Technology, LTC1644CGN#PBF Datasheet
LTC1644CGN#PBF
Specifications of LTC1644CGN#PBF
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LTC1644CGN#PBF Summary of contents
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... I/O pins during card insertion and extraction. PCI_RST# is combined on-chip with HEALTHY# in order to generate LOCAL_PCI_RST#. , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. CompactPCI is a trademark of the PCI Industrial Computer Manufacturers Group. ...
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LTC1644 ABSOLUTE AXI U RATI GS (Note 1) Supply Voltages 12V ................................................................ 13. .................................................................. –14V EEIN Input Voltages (Pins 5, 9) .......................– 0.3V to 13.5V Output Voltages (Pins 6, 7, 10) ..............– 0.3V to 13.5V ...
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ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are 12V –12V 3.3V, V 12VIN EEIN 3VIN SYMBOL PARAMETER V Power Good Threshold Voltage TH ...
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LTC1644 W U TYPICAL PERFOR A CE CHARACTERISTICS 3.3V and 5V Current Foldback Profile OUT OUT 0.005 SENSE 0 0 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS 5V/3.3V Circuit Breaker Trip Voltage vs Temperature 56.2 TIMER PIN FLOATING 56.0 55.8 55.6 55.4 55.2 55.0 54.8 –50 – 100 TEMPERATURE ( C) 1644 G10 GATE Pin Current ...
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LTC1644 W U TYPICAL PERFOR A CE CHARACTERISTICS 12V Foldback Current Limit vs Temperature 1.00 0.90 12V = 10V OUT 0.80 0.70 0.60 0.50 12V = 0V OUT 0.40 0.30 0.20 0.10 0 –50 – 100 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS 3V Input Current SENSE vs Temperature OUT OUT 0 50 100 –50 – TEMPERATURE ( C) 1644 G28 ...
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LTC1644 W U TYPICAL PERFOR A CE CHARACTERISTICS 3V Discharge Resistance OUT vs Temperature –50 – 100 TEMPERATURE ( C) 1644 G37 V vs Temperature OL ...
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CTIO S OFF/ON (Pin 5): Digital Input. Connect the CPCI BD_SEL# signal to the OFF/ON pin. When the OFF/ON pin is pulled low, the GATE pin is pulled high current source ...
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LTC1644 CTIO S When the TIMER pin is high, the circuit breaker function is enabled. If the voltage across the sense resistor exceeds 55mV but is less than 150mV, the circuit breaker is tripped after ...
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DIAGRA S t Overcurrent Fault Detect 3.3V FALL TIME 5VSENSE 100mV V 3VSENSE t OC FAULT 1644 TD01 U U APPLICATIO S I FOR ATIO Hot Circuit ...
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LTC1644 U U APPLICATIO S I FOR ATIO Power-Up Sequence The LTC1644 is specifically designed for live insertion and removal of CPCI boards. The typical application is shown in Figure 1. The 3.3V, 5V, 12V and –12V inputs to the ...
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U U APPLICATIO S I FOR ATIO TIMER 10V/DIV GATE 5V/DIV 12V OUT 10V/DIV 5V OUT 10V/DIV 3V OUT 10V/DIV V EEOUT 10V/DIV BD_SEL# 5V/DIV LOCAL_PCI_RST# 5V/DIV HEALTHY# 5V/DIV PRECHARGE 5V/DIV 10ms/DIV Figure 2. Normal Power-Up Sequence TIMER During a ...
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LTC1644 U U APPLICATIO S I FOR ATIO Table TIMER TIMER TIMER TIMER TIMER 0.01 F 5.24ms 0.22 F 0.022 F 11.5ms 0.33 F 0.033 F 17.3ms 0.47 F 0.047 F 24.6ms 0.68 ...
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U U APPLICATIO S I FOR ATIO LOCAL_PCI_RST# PRECHARGE TIMER 10V/DIV GATE 10V/DIV 5V – SENSE 100mV/DIV FAULT 5V/DIV 20 s/DIV Figure 5. Overcurrent Fault TIMER 10V/DIV GATE 5V/DIV 12V OUT 10V/DIV 5V OUT ...
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LTC1644 U U APPLICATIO S I FOR ATIO Calculating R SENSE An equivalent circuit for one of the LTC1644’s circuit breakers useful in calculating the value of the sense resistor is shown in Figure 7. To determine the most appropriate ...
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U U APPLICATIO S I FOR ATIO Output Voltage Monitor The status of all four output voltages is monitored by the power good function. In addition, the PCI_RST# signal is logically combined on-chip with the HEALTHY# signal to create LOCAL_PCI_RST# ...
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LTC1644 U U APPLICATIO S I FOR ATIO LTC1644* GND PRECHARGE DRIVE 4.7nF 18 R10A R10B MMBT2222A PRECHARGE OUT R10A V = • 1V PRECHARGE R10A + R10B *ADDITIONAL DETAILS OMITTED FOR CLARITY Figure 8. ...
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U U APPLICATIO S I FOR ATIO C8 0.1 F PCB EDGE PER 10 BACKPLANE BACKPLANE POWER CONNECTOR CONNECTOR PINS 5V LONG 5V 3.3V LONG 3. 12V 5V BD_SEL# EARLY V(I/O) R17 2k HEALTHY# PCI_RST# R15 ...
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LTC1644 U U APPLICATIO S I FOR ATIO PCB EDGE BACKPLANE BACKPLANE CONNECTOR CONNECTOR 5V LONG 5V GROUND D1, D2: BAV99 Z4: 1PMT5.0AT3 *ADDITIONAL PINS OMITTED FOR CLARITY BD_SEL# GROUND restricts the choice of power MOSFETs to those devices with ...
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U U APPLICATIO S I FOR ATIO sinusoidal response whose duration and period is depen- dent on the resonant circuit parameters. Since the abso- lute maximum supply voltage of the LTC1644 is 13.2V, transient protection against 12V IN age spikes ...
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LTC1644 U U APPLICATIO S I FOR ATIO PCB Layout Considerations For proper operation of the LTC1644’s circuit breaker operation, 4-wire Kelvin-sense connections between the sense resistor and the LTC1644’s 5V and 3V and 3V pins are strongly recommended. IN ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Dual ON Pins for Supplies from 3V to 15V Single Supply, 2.5V to 16.5V, MSOP 1.7V to 16.5V Operation, Multifunction Current Control – 20V to – 80V, Active Current Limiting Floating Supply, Active Current Limiting and Fast Circuit Breaker LT/TP 0203 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2001 1644f ...