LTC3723-2 Linear Technology, LTC3723-2 Datasheet
LTC3723-2
Related parts for LTC3723-2
LTC3723-2 Summary of contents
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... The LTC3723-1 features peak current mode control with programmable slope compensation and lead- ing edge blanking, while the LTC3723-2 employs voltage mode control with voltage feedforward capability. The LTC3723-1/LTC3723-2 feature extremely low operat- ing and start-up currents ...
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... LTC3723-1/LTC3723 ABSOLUTE AXI U RATI GND (Low Impedance Source) .......– 0.3V to 10V CC (Chip Self-Regulates at 10.3V) UVLO to GND ............................................. – 0. All Other Pins to GND (Low Impedance Source) .........................– 0.3V to 5.5V V (Current Fed) ................................................. 40mA CC U PACKAGE/ORDER I FOR ATIO TOP VIEW V 1 REF SDRB 2 SDRA ...
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... TF(x) Fall-Time Current Limit and Shutdown CLPP Pulse by Pulse Current Limit Threshold CLSD Shutdown Current Limit Threshold CLDEL Current Limit Delay to Output LTC3723-1/LTC3723-2 The ● denotes the specifications which apply over the full operating = 25° 9.5V unless otherwise noted CONDITIONS Measured on CS, C ...
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... LTC3723-1/LTC3723-2 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER SSI Soft-Start Current SSR Soft-Start Reset Threshold FLT Fault Reset Threshold Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Includes leading edge blanking delay, R production ...
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... TEMPERATURE (°C) 350 300 250 200 150 100 50 0 – 125 372312 G13 LTC3723-1/LTC3723-2 www.DataSheet4U.com (T = 25°C unless otherwise noted) A LTC3723 Deadtime vs R With and Without 200k Prebias Compensation 275 250 225 200k PREBIAS 200 175 150 NO 200k PREBIAS ...
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... GND to program from 40ns to 310ns of leading LEB edge blanking of the current sense signal on CS for the LTC3723-1. A ±1% tolerance resistor is recommended. The LTC3723-2 has a fixed blanking time of approximately 80ns. The nominal voltage on R blanking is not required, tie R FB (Pin 13/Pin 13): Error Amplifier Inverting Input. This is the voltage feedback input for the LTC3723 ...
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... SS (Pin 14/Pin 14): Soft-Start/Restart Delay Circuitry Timing Capacitor. A capacitor from SS to GND provides a controlled ramp of the current command (LTC3723-1) or duty cycle (LTC3723-2). During overload conditions discharged to ground initiating a soft-start cycle. SS charging current is approximately 13µA. SS will charge up to approximately 5V in normal operation. During a con- stant overload current fault, SS will oscillate at a low frequency between approximately 0 ...
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... LTC3723-1/LTC3723-2 W BLOCK DIAGRA S V UVLO UVLO CC 10µA 10.25V “ON” “OFF” ERROR SYSTEM AMPLIFIER UVLO – – 1.2V 5V 50k – COMP 11 14. 650mV – + – V REF 13µ SHUTDOWN CURRENT LIMIT + – 600mV PULSE-BY-PULSE CURRENT LIMIT ...
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... RAMP 9 + – V REF 13µ SHUTDOWN CURRENT LIMIT FAULT + LOGIC – 600mV PULSE-BY-PULSE CURRENT LIMIT + CS 10 BLANK – 300mV LTC3723-2 Block Diagram V C REF REF, LDO 5V 1.2V REF GOOD V CC GOOD OSCILLATOR GND LTC3723-1/LTC3723-2 www ...
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... CS exceeds 300mV, the present cycle is termi- nated. If the voltage on CS exceeds 600mV, all switching stops and a soft-start sequence is initiated. The LTC3723-1 / LTC3723-2 also provide drive signals for secondary side synchronous rectifier MOSFETs. Synchro- nous rectification improves converter efficiency, espe- cially as the output voltages drop ...
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... • t HOLDUP CC DRIVE DELAY (minimum UVLO hysteresis) Regulated bias supplies as low as 7V can be utilized to provide bias to the LTC3723-1/LTC3723-2. Refer to Figure 2 for various bias supply configurations. 12V ±10% V < V BIAS UVLO 1N5226 1N914 1.5k 3V 1µF ...
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... Also note that higher switching frequency and added driver dead-time via DPRG will reduce the maximum duty cycle. The LTC3723-1/LTC3723-2 can be synchronized to an external frequency source such as another PWM chip Figure 5, the leading edge of an external pulse is used to terminate the natural clock cycle ...
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... V C • ⎜ ⎟ µ µ + ⎝ ⎠ 210 A 210 Figure 10. LTC3723-2 Open Loop Control (Duty Cycle is Inversely Proportional to Input Voltage) ⎛ ⎞ • T ⎜ – T ⎟ DPRG SW ⎝ µ ⎠ 210 A 372312 F08 LTC3723-1/LTC3723-2 www ...
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... Current sensing provides feedback for the current mode control loop and protection from overload conditions. The LTC3723-1/LTC3723-2 are compatible with either resis- tive sensing or current transformer methods. Internally connected to the LTC3723-1/LTC3723-2 CS pin are two comparators that provide pulse-by-pulse and overcurrent shutdown functions respectively, (Figure 12). LTC3723 ...
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... U OPERATIO High Current Drivers The LTC3723-1/LTC3723-2 high current, high speed driv- ers provide direct drive of external power N-channel MOSFET switches. The drivers swing from rail to rail. Due to the high pulsed current nature of these drivers (1.5A sink, 1A source), care must be taken with the board layout to obtain advertised performance ...
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... LTC3723-1/LTC3723-2 U TYPICAL APPLICATIO S 16 www.DataSheet4U.com 372312f ...
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... U TYPICAL APPLICATIO S LTC3723-1/LTC3723-2 www.DataSheet4U.com 372312f 17 ...
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... LTC3723-1/LTC3723-2 U TYPICAL APPLICATIO S 18 www.DataSheet4U.com 372312f ...
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... U GN Package 16-Lead Plastic SSOP (Narrow .150 Inch) (Reference LTC DWG # 05-08-1641 .004 – .0098 (0.102 – 0.249) .229 – .244 .0250 (5.817 – 6.198) (0.635) BSC LTC3723-1/LTC3723-2 www.DataSheet4U.com ES1B V F 1nF 100V 10Ω 1W ES1B ...
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... LTC3723-1/LTC3723-2 U TYPICAL APPLICATIO LTC3723-1 100W, 36V 0.33µ 1µF 1µF 100V 100V ×2 – 48V LOAD CURRENT (A) V 10V IN A 30k 6 4 150Ω DRVA DRVB 1/ 383k LTC3723EGN-1 15 UVLO GND SS ...