LTC3721-1 Linear Integrated Systems, LTC3721-1 Datasheet
LTC3721-1
Related parts for LTC3721-1
LTC3721-1 Summary of contents
Page 1
... Dead-time is independently pro- grammed with an external resistor. A UVLO program input provides precise system turn-on and turn off voltages. The LTC3721-1 features peak current mode control with pro- grammable slope compensation and leading edge blanking. The LTC3721-1 features extremely low operating and start-up currents and reliable short-circuit and overtemperature protection ...
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... System UVLO Threshold SHYST System UVLO Hysteresis Current DataSheet4U.com (Note 1) V REF Operating Temperature (Notes 5,6) LTC3721-1 ......................................... – 40°C to 85°C CC Storage Temperature Range ................. – 65°C to 125°C Lead Temperature (GN Package only) (Soldering, 10sec) ............................................ 300° ORDER PART NUMBER LTC3721EGN-1 ...
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... Shorted to GND REF I = –100mA OUT( 100mA OUT( –10mA to –100mA OUT( –10mA to –100mA OUT( 1nF OUT( 1nF OUT(x) Measured on CS Measured on CS 100mV Overdrive on CS, (Note 2.5V LTC3721-1 MIN TYP MAX UNITS 0. µA 68 µA ● ● 130 ns 220 250 ...
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... LTC3721-1 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER 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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... Shunt Voltage vs CC Temperature 10 10mA CC 10.4 10.3 DataSheet4U.com 10.2 10.1 10.0 9.9 9.8 –55 – 125 TEMPERATURE (°C) 372311 G10 LTC3721 25°C unless otherwise noted) A Deadtime vs R DPRG 275 250 225 200k PREBIAS 200 175 150 125 100 100 150 200 250 65 95 125 R (kΩ ...
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... PCB trace from the driver to the MOSFET cannot be made short. GND (Pin 7/Pin 4, Pin 5, Pin 17): All circuits in the LTC3721-1 are referenced to GND. Use of a ground plane is highly recommended. V must be terminated with a star configuration as close to DataSheet4U.com ...
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... U PI DESCRIPTIO S FB (Pin 13/Pin 12): Error Amplifier Inverting Input. This is the voltage feedback input for the LTC3721-1. The nomi- nal regulation voltage 1.2V. SS (Pin 14/Pin 13): Soft-Start/Restart Delay Circuitry Timing Capacitor. A capacitor from SS to GND provides a controlled ramp of the current command. During overload conditions discharged to ground initiating a soft- start cycle. SS charging current is approximately 13µ ...
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... LTC3721-1 BLOCK DIAGRA S DataSheet4U.com 8 W DataSheet4U.com sn37211 37211fs ...
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... U OPERATIO Please refer to the detailed Block Diagram for this discus- sion. The LTC3721 PWM push-pull controller that operates with pulse-by-pulse peak current mode control best suited for moderate to high power isolated power systems where small size and high efficiency are required. ...
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... HOLDUP CC DRIVE (minimum UVLO hysteresis) Regulated bias supplies as low as 7V can be utilized to provide bias to the LTC3721-1. Refer to Figure 2 for various bias supply configurations. Programming Undervoltage Lockout The LTC3721-1 provides undervoltage lockout (UVLO) control for the input DC voltage feed to the power con- ...
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... PWM cycle is terminated, the soft-start capacitor is quickly discharged and a soft-start cycle is initiated. If the overcurrent condi- tion persists, the LTC3721-1 halts PWM operation and waits for the soft-start capacitor to charge up to approxi- mately 4V before a retry is allowed. The soft-start capaci- . Typical maximum duty cycles tor is charged by an internal 13µ ...
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... Transformer Configurations The LTC3721-1 used in a typical isolated push-pull con- verter application will need a transformer to provide the voltage translation and galvanic isolation. The push-pull transformer employs a center tapped primary winding configuration ...
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... U OPERATIO The duty cycle of these square waves is guaranteed to never exceed 50% by the LTC3721-1. In steady state operation, the duty ratio is given by /(2 • V • N) OUT IN To calculate the transformer turns ratio, first determine the minimum input voltage (V duty ratio ( the controller IC. This will be the (MAX) worst case condition ...
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... LTC3721-1 PACKAGE DESCRIPTIO .254 MIN .0165 ± .0015 RECOMMENDED SOLDER PAD LAYOUT .007 – .0098 (0.178 – 0.249) NOTE: 1. CONTROLLING DIMENSION: INCHES 2. DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" ...
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... 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. LTC3721-1 BOTTOM VIEW—EXPOSED PAD R = 0.115 0.55 ± ...
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... LTC3721-1 TYPICAL APPLICATIO 5.1Ω C2, C3, C4, C5 1/2W 4x33µF 12V 16V IN – 73.2k 4.7Ω 1/4W 330pF FMMT718 V IN 470Ω MMBT3904LT1 6 10 DRVA 470Ω 107k LTC3721EGN-1 15 UVLO LEB 8 12 1nF 1µF D1 9.1V 270pF 33k 100k RELATED PARTS PART NUMBER ...