lt1766efe-trpbf Linear Technology Corporation, lt1766efe-trpbf Datasheet

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... The LT1766/LT1766-5 are available in a 16-pin fused-lead SSOP package or a TSSOP package with exposed backside for improved thermal performance. , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. *Protected by U.S. Patents including 6498466, 6531909 1N4148W 0.33µ ...

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... SENSE Voltage (LT1766-5) SENSE Pin Resistance (LT1766-5) FB Input Bias Current (LT1766 Operating Junction Temperature Range LT1766EFE/LT1766EFE-5/LT1766EGN/ LT1766EGN-5 (Note 8,10) ................. – 40°C to 125°C LT1766IFE/LT1766IFE-5/ LT1766IGN/LT1766IGN-5 (Note 8,10) – 40°C to 125°C LT1766HGN/LT1766HFE ................... – 40°C to 140°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300° ...

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ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are 15V 1.5V, SHDN = 1V, BOOST open circuit, SW open circuit, unless otherwise noted PARAMETER ...

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... C forced current. See Typical Performance Characteristics for the graph of switch voltage at other currents. Note 8: The LT1766EGN, LT1766EGN-5, LT1766EFE and LT1766EFE-5 are guaranteed to meet performance specifications from 0°C to 125°C junction temperature. Specifications over the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Switch Peak Current Limit 2 25°C A TYPICAL 2.0 GUARANTEED MINIMUM 1.5 1 100 DUTY CYCLE (%) 1766 G01 Lockout and Shutdown Thresholds 2.4 LOCKOUT 2.0 ...

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LT1766/LT1766 TYPICAL PERFOR A CE CHARACTERISTICS Switching Frequency 230 220 210 200 190 180 170 0 –50 – 100 125 150 JUNCTION TEMPERATURE (°C) 1766 G10 V Pin Shutdown Threshold C 2.1 1.9 1.7 1.5 ...

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CTIO S V (Pin 4): This is the collector of the on-chip power NPN IN switch. V powers the internal control circuitry when a IN voltage on the BIAS pin is not present. High dI/dt ...

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LT1766/LT1766-5 W BLOCK DIAGRA The current fed system will have 90° phase shift at a much lower frequency, but will not have the additional 90° shift until well beyond the LC resonant frequency. This makes it much easier to frequency ...

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U U APPLICATIO S I FOR ATIO FEEDBACK PIN FUNCTIONS The feedback (FB) pin on the LT1766 is used to set output voltage and provide several overload protection features. The first part of this section deals with selecting resistors to ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO LT1766 AMPLIFIER Q2 V GND C should be used if resistors are increased beyond the suggested values and short-circuit conditions occur with high input voltage. High frequency pickup will increase and the ...

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U U APPLICATIO S I FOR ATIO where: ESR = equivalent series resistance of the output capacitor ESL = equivalent series inductance of the output capacitor dI/dt = slew rate of inductor ripple current = V Peak-to-peak ripple current (I ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO materials fall somewhere in between. The following for- mula assumes continuous mode of operation, but errs only slightly on the high side for discontinuous mode can be used for all ...

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U U APPLICATIO S I FOR ATIO Discontinuous mode is entered when the output load current is less than one-half of the inductor ripple current ( this mode, inductor current falls to zero before LP-P the next switch ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO its normal value. Below this point the oscillator frequency decreases roughly linearly down to a limit of about 40kHz. This lower oscillator frequency during short-circuit condi- tions can then maintain control with ...

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U U APPLICATIO S I FOR ATIO INPUT CAPACITOR Step-down regulators draw current from the input supply in pulses. The rise and fall times of these pulses are very fast. The input capacitor is required to reduce the voltage ripple ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO BOOST PIN For most applications, the boost components are a 0.33µF capacitor and a 1N4148W diode. The anode is typically connected to the regulated output voltage to generate a voltage approximately V ...

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U U APPLICATIO S I FOR ATIO Keep the connections from the resistors to the shutdown pin short and make sure that interplane or surface capaci- tance to the switching nodes are minimized. If high resistor values are used, the ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO MINIMIZE LT1766 C3-D1 LOOP GND V IN rating. A ground plane should always be used under the switcher circuitry to prevent interplane coupling and over- all noise. The V and FB components ...

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U U APPLICATIO S I FOR ATIO SW RISE SW FALL 2V/DIV 50ns/DIV Figure 7. Switch Node Resonance switch off spike will also cause the SW node to go below ground. The LT1766 has special circuitry inside which mitigates this ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO Thermal resistance for the LT1766 packages is influenced by the presence of internal or backside planes. SSOP (GN16) Package: With a full plane under the GN16 package, thermal resistance will be about ...

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U U APPLICATIO S I FOR ATIO voltage required for full saturation of the internal power switch. For output voltages of 5V During switch turn on, V will fall as the boost capacitor dicharged by ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO V control voltage to the point where some sort of cycle- C skipping or odd/even cycle behavior is exhibited. In summary aware that the simultaneous requirements of high V , ...

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U U APPLICATIO S I FOR ATIO When using R , the maximum value has two limitations. C First, the combination of output capacitor ESR and R stop the loop rolling off altogether. Second, if the loop gain is not ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO ( )( )( ) OUT = RiseTime V BE Using the values shown in Figure 10 – • • = ...

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U U APPLICATIO S I FOR ATIO I = Maximum rated switch current Minimum input voltage Output voltage OUT V = Catch diode forward voltage F 0.3 = Switch voltage drop at 1.5A Example: ...

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LT1766/LT1766 APPLICATIO S I FOR ATIO load currents and L ≥15µH. It increases to about 2.0 for smaller inductors at lower load currents Input Capacitor RMS OUT ff = 1.2 to 2.0 ...

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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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... High Efficiency OUT Step-Down DC/DC Converters LT3433 High Voltage, Micropower (I LTC3727/LTC3727-1 36V, 500kHz, High Efficiency Step-Down DC/DC Controllers ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ) Constant 1.1MHz, High Efficiency , = 100µ ...