LTC4244IGN-1#PBF Linear Technology, LTC4244IGN-1#PBF Datasheet
LTC4244IGN-1#PBF
Specifications of LTC4244IGN-1#PBF
Related parts for LTC4244IGN-1#PBF
LTC4244IGN-1#PBF Summary of contents
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... LTC4244-1 Designed for Applications without –12V Available in 20-Lead Narrow SSOP Package U APPLICATIO S Hot Board Insertion into CompactPCI Bus , 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. U TYPICAL APPLICATIO C8 0 ...
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... – 100mA VEE EEOUT EEIN ORDER PART TOP VIEW NUMBER 20 12V OUT 19 V LTC4244CGN EEOUT 18 3.3V LTC4244CGN-1 OUT 17 3.3V LTC4244IGN IN 16 3.3V LTC4244IGN-1 SENSE 15 GATE 14 5V SENSE PRECHARGE 11 DRIVE GN PACKAGE = 140 C, = 135 3.3V 5V, unless 3.3VIN 5VIN MIN TYP MAX 4.25 4 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T otherwise noted. SYMBOL PARAMETER I Current Foldback CL T Thermal Shutdown Temperature TS V Power Good Threshold Voltage TH V Logic Input Low Voltage IL V Logic Input High Voltage IH ...
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LTC4244/LTC4244 TYPICAL PERFOR A CE CHARACTERISTICS 3.3V and 5V Current Foldback Profile VOLTAGE (V) 4244 G01 12V Foldback Current Limit vs Temperature 0.9 12V ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS 3.3V and 5V Circuit Breaker IN IN Trip Voltage vs Temperature 52.0 51 51.6 51.4 51.2 51.0 3.3V 50.8 IN 50.6 50.4 50.2 50.0 –50 – 100 ...
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LTC4244/LTC4244 TYPICAL PERFOR A CE CHARACTERISTICS 5V Powergood Threshold OUT Voltage vs Temperature 4.603 4.602 4.601 4.600 4.599 4.598 4.597 4.596 4.595 4.594 –50 – 100 TEMPERATURE ( C) 4244 G19 Gate Pin Fault ...
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CTIO S 12V (Pin 1): 12V Supply Input. A 0.5 switch is con- IN nected between 12V and 12V with a foldback current IN OUT limit. An undervoltage lockout circuit prevents the switches from turning ...
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LTC4244/LTC4244 CTIO S RESETOUT (Pin 10): Open-Drain Digital Output. Connect the CPCI_LOCAL_RST# signal to the RESETOUT pin. RESETOUT is the logical combination of the RESETIN and PWRGD. DRIVE (Pin 11): Precharge Base Drive Output. Provides ...
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CTIO S 3.3V (Pin 17): 3.3V Supply Sense Input. An undervolt- IN age lockout circuit prevents the switches from turning on when the voltage at the 3.3V pin is less than 2.5V ...
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LTC4244/LTC4244-1 W BLOCK DIAGRA 3. 3.3V SENSE 16 GATE 15 5V SENSE – + – 5V CURRENT 50mV FAULT + + + – – TIMER_LO 50mV TIMER_HI 150mV 8 s UVL RISING MONITOR ...
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U U APPLICATIO S I FOR ATIO Hot Circuit Insertion When a circuit board is inserted into a live CompactPCI (CPCI) bus, the supply bypass capacitors can draw huge inrush currents from the CPCI power bus as they charge up. ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO • 5V UVL Threshold Voltage: The LTC4244’ threshold voltage is 4.25V vs. 2.5V for the LTC1644. • V PWRGD Threshold Voltage: The LTC4244 V EEOUT power good threshold voltage is ...
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U U APPLICATIO S I FOR ATIO Sense resistors R1 and R2 provide current fault detection and R5 and C1 provide current control loop compensation as well as ramp rate control for the GATE pin voltage. Resistors R3 and R4 ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO Once the power-down sequence is complete, the CPCI card may be removed from the slot. During extraction, the precharge circuit continues to bias the bus I/O connector pins at 1V until the ...
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U U APPLICATIO S I FOR ATIO Table TIMER TIMER C ( 10%) t TIMER TIMER(MIN) 0.1 F 35ms 0.22 F 77ms 0.33 F 115ms 0.47 F 164ms 0.68 F 238ms 0.82 F 287ms The TIMER ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO immediately to its I value. If that supply remains in LIMIT current limit for more than 25 s, all of the supplies will be latched off. The 25 s prevents quick current ...
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U U APPLICATIO S I FOR ATIO Calculating R SENSE Determining the most appropriate value for the sense resistor first requires knowing the maximum current needed by the load under worst-case conditions. Two other pa- rameters affect the value of ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO LTC4244* GND PRECHARGE DRIVE 4.7nF 5% R10A R10B Q3 PRECHARGE OUT MMBT2222A R10A V = • 1V PRECHARGE R10A + R10B *ADDITIONAL DETAILS OMITTED FOR CLARITY Figure 7. ...
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U U APPLICATIO S I FOR ATIO BD_SEL# voltage drops below 4.4V thus causing the bus switch pulled high by Q2. The CompactPCI specification assumes that there is a diode to 3.3V on the circuit that is ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO Power MOSFET Selection Criteria The LTC4244 uses external MOSFETs to limit the 5V and 3.3V supply currents. The following criteria should be used when selecting these MOSFET’s: 1. The on resistance should ...
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U U APPLICATIO S I FOR ATIO are experimentally determined based on the board’s para- sitic resonance circuits starting point, the capacitors in these networks are chosen 100 the power MOSFET’s C under bias. ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO PCB Layout Considerations For proper operation of the LTC4244’s circuit breaker, 4-wire Kelvin sense connections between the sense resis- tor and the LTC4244’s 5V and 5V IN and 3.3V pins are strongly ...
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U U APPLICATIO S I FOR ATIO the PC board. For 1 ounce copper foil plating, a general rule is 1 ampere of DC current per via making sure the via is properly dimensioned so that solder completely fills the ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO The next step is to verify that the thermal ratings of the external 5V and 3.3V MOSFETs aren’t being exceeded during power-up cycles into the designed loads or into a short circuit. ...
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U U APPLICATIO S I FOR ATIO The IRF7457’s Thermal Response vs Pulse Duration curve indicates that the worst-case increase in junction-to- ambient temperature during a power-cycle for the 3.3V MOSFET is less than 96 C while the worst-case increase ...
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LTC4244/LTC4244 APPLICATIO S I FOR ATIO Table 7. Sense Resistor Selection Guide CURRENT LIMIT VALUE PART NUMBER 1A LR120601R055F WSL1206R055 2A LR120601R028F WSL1206R028 5A LR120601R011F WSL2010R011 7.6A WSL2512R007 10A WSL2512R005 Table 8. N-Channel Power MOSFET Selection Guide CURRENT ...
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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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... OUT + C LOAD(12VOUT) V EEOUT TIMER C2 0.082 F R6 10k RESETOUT DRIVE LOCAL_PCI_RST 3. MMBT2222A 1V RESET# 10% I/O #1 PCI • • BRIDGE • I/O #128 CHIP 4244 F17 LT/TP 0204 1K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2003 V OUT OUT 3. OUT 12V 500mA V OUT 3.3V 42441f ...