LTC3722EGN-1#PBF Linear Technology, LTC3722EGN-1#PBF Datasheet

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... Both devices include a full range of protection features and are available in the 24-pin surface mount GN package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and DirectSense is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...

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... NARROW PLASTIC SSOP T = 125°C, θ = 100°C/W JMAX JA orDer inForMaTion LEAD FREE FINISH TAPE AND REEL LTC3722EGN-1#PBF LTC3722EGN-1#TRPBF LTC3722EGN-2#PBF LTC3722EGN-2#TRPBF LTC3722IGN-1#PBF LTC3722IGN-1#TRPBF LTC3722IGN-2#PBF LTC3722IGN-2#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. ...

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T SYMBOL PARAMETER Input Supply V V Under Voltage Lockout CCUV UVLO Hysteresis CCHY CC I Start-Up Current CCST I Operating Current CCRN V Shunt Regulator Voltage SHUNT R ...

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LTC3722-1/LTC3722-2 elecTrical characTerisTics temperature range, otherwise specifications are at T SYMBOL PARAMETER Error Amplifier V FB Input Voltage FB FBI FB Input Range A Open-Loop Gain VOL IIB Input Bias Current V Output High OH V Output Low OL I ...

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Typical perForMance characTerisTics Start- 200 T = 25°C A 150 100 (V) CC 372212 G01 Leading Edge Blanking Time vs R LEB 350 T = 25°C A ...

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LTC3722-1/LTC3722-2 Typical perForMance characTerisTics Slope Current vs Temperature 2.25V –55 – TEMPERATURE (°C) 3722 • G10 FB Input Voltage ...

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FuncTions (LTC3722-1/LTC3722-2) SYNC (Pin 1/Pin 1): Synchronization Input/Output for the Oscillator. The input threshold for SYNC is approximately 1.9V, making it compatible with both CMOS and TTL logic. Terminate SYNC with a 5.1k resistor to GND. DPRG (Pin 2/Pin ...

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LTC3722-1/LTC3722-2 pin FuncTions (LTC3722-1/LTC3722-2) OUTC (Pin 19/Pin 19): 50mA Driver for High Side of the Full Bridge Active Leg. OUTB (Pin 20/Pin 20): 50mA Driver for Low Side of the Full Bridge Passive Leg. OUTA (Pin 21/Pin 21): 50mA Driver ...

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DiagraM V UVLO UVLO CC REF AND LDO 10.25V = OFF REF GOOD SYSTEM FB ERROR UVLO AMPLIFIER – – 1. COMP 50k – ...

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LTC3722-1/LTC3722-2 TiMing DiagraM OUTA OUTB OUTC OUTD RAMP COMP OUTE OUTF NOTE: SHADED AREAS CORRESPOND TO POWER DELIVERY PULSES. operaTion Phase-Shift Full Bridge PWM Conventional full bridge switching power supply topologies are often employed for high power, isolated DC/DC and ...

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Internally generated drive signals with programmable turn-off for current doubler synchronous rectifiers. Benefit: eliminates external glue logic, drivers, optimal timing for highest efficiency. 4. Programmable (single resistor) leading edge blanking. Benefit: prevents spurious operation, reduces external filtering required ...

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LTC3722-1/LTC3722-2 operaTion State 1 POWER PULSE State 2 ACTIVE TRANSITION MA MB State 3 PASSIVE TRANSITION MA MB State 4 POWER PULSE L01 MC N:1 L02 + MD MF ...

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That is, 1/2 • (LM + LI) • IM2 > 1/2 • 2 • COSS • V ...

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LTC3722-1/LTC3722-2 operaTion network to implement. If there is not enough energy to fully commutate the bridge leg to a ZVS condition, the LTC3722-1/LTC3722-2 automatically overrides the Di- rectSense circuitry and forces a transition. The override or default delay time is ...

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Fixed Delay Mode The LTC3722-1/LTC3722-2 provides the flexibility through the SBUS pin to disable the DirectSense delay circuitry and enable fixed ZVS delays. The level of fixed ZVS delay is proportional to the voltage programmed through the voltage divider ...

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LTC3722-1/LTC3722-2 operaTion Regulated bias supplies as low as 7V can be utilized to provide bias to the LTC3722-1/LTC3722-2. Figure 5 shows various bias supply configurations. V < V 12V 10% BIAS UVLO 1N5226 1N914 1.5k 3V 0.1µ ...

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An advantage of this technique over the previous is that it does not require a separate filter inductor and since the voltage ...

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LTC3722-1/LTC3722-2 operaTion 3. Slope compensation is required for most peak current mode controllers in order to prevent subharmonic oscillation of the current control loop. In general, if the system duty cycle exceeds 50 fixed frequency, continuous current mode ...

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Current Sensing and Overcurrent Protection Current sensing provides feedback for the current mode control loop and protection from overload conditions. The LTC3722-1/LTC3722-2 are compatible with either resis- tive sensing or current transformer methods. Internally connected to the LTC3722-1/LTC3722-2 CS ...

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LTC3722-1/LTC3722-2 operaTion output current for the converter can be delivered at the lowest expected V . Use the following formula to calculate IN the optimal value for equation valid for current CS P doubler secondary. LTC3722-1: 300 ...

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Phase Modulator (LTC3722-1) The LTC3722-1 phase modulation control circuitry is comprised of the phase modulation comparator and logic, the error amplifier, and the soft-start amplifier (see Figure 12). Together, these elements develop the required phase overlap (duty cycle) required ...

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LTC3722-1/LTC3722-2 operaTion Power Transformer Switching frequency, core material characteristics, series resistance and input/output voltages all play an important role in transformer selection. Close attention also needs to be paid to leakage and magnetizing inductances as they play an important role ...

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Without snubbing, the secondary voltage can ring to levels far beyond what is expected due to the resonant tank circuit formed between the secondary leakage inductance and the C (output capacitance) of OSS the synchronous rectifier ...

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LTC3722-1/LTC3722-2 operaTion loop is very helpful tool to quickly evaluate the frequency response of various compensation networks. Polymer Electrolytic (see Figure 13) 1/(2πC low frequency pole. 1/(2π sets the low frequency C F zero. The zero frequency should ...

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The drive to the inductors is 180 degrees out- of-phase which provides partial ripple current cancellation in the output capacitor(s). Reduced capacitor ripple current lowers output voltage ripple and enhances the capacitors’s reliability. The amount of ripple cancellation ...

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LTC3722-1/LTC3722-2 package DescripTion .254 MIN .0165 ± .0015 RECOMMENDED SOLDER PAD LAYOUT .0075 – .0098 (0.19 – 0.25) .016 – .050 (0.406 – 1.270) NOTE: 1. CONTROLLING DIMENSION: INCHES INCHES 2. DIMENSIONS ARE IN (MILLIMETERS) 3. DRAWING NOT TO SCALE ...

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... I-grade parts added. Reflected throughout the data sheet. 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. ...

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... V COMP R TOP LT1431 8 1 COLL REF D12 GNDF GNDS R MID 2.49k 5. –V OUT LT 0310 REV A • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2009 13k 1/2W +V OUT 0.47µF 100V OUT +V OUT 12V 35A 1µF –V OUT +V OUT 1k MMBT3904 100 D10 10V 1µ ...