LT1766EGN-5#PBF Linear Technology, LT1766EGN-5#PBF Datasheet
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LT1766EGN-5#PBF
Specifications of LT1766EGN-5#PBF
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LT1766EGN-5#PBF Summary of contents
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... SSOP package or a TSSOP package with exposed backside for improved thermal performance. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and ThinSOT is a trademark 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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... JC EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB 2 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 LT1766HFE ..........................................–40°C to 140°C Storage Temperature Range .................. –65°C to 150°C Lead Temperature (Soldering, 10 sec) .................. 300°C ...
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... LEAD FREE FINISH TAPE AND REEL LT1766EFE#PBF LT1766EFE#TRPBF LT1766IFE#PBF LT1766IFE#TRPBF LT1766HFE#PBF LT1766HFE#TRPBF LT1766EFE-5#PBF LT1766EFE-5#TRPBF LT1766IFE-5#PBF LT1766IFE-5#TRPBF LT1766EGN#PBF LT1766EGN#TRPBF LT1766IGN#PBF LT1766IGN#TRPBF LT1766EGN-5#PBF LT1766EGN-5#TRPBF LT1766IGN-5#PBF LT1766IGN-5#TRPBF LEAD BASED FINISH TAPE AND REEL LT1766EFE LT1766EFE#TR LT1766IFE LT1766IFE#TR LT1766HFE LT1766HFE#TR LT1766EFE-5 LT1766EFE-5#TR LT1766IFE-5 LT1766IFE-5#TR LT1766EGN ...
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LT1766/LT1766-5 ELECTRICAL CHARACTERISTICS l The denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are 1.5V, SHDN = 1V, BOOST open circuit, SW open circuit, unless otherwise noted 15V, V ...
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... 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 specifi cations from 0°C to 125°C junction temperature. Specifi cations 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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LT1766/LT1766-5 TYPICAL PERFORMANCE 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 1.6 1.2 0.8 ...
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TYPICAL PERFORMANCE 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 1.3 1.1 0.9 0.7 –50 ...
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LT1766/LT1766-5 PIN FUNCTIONS 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 edges occur on this ...
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BLOCK DIAGRAM 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 compensate the feedback loop and also ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION FEEDBACK PIN FUNCTIONS The feedback (FB) pin on the LT1766 is used to set output voltage and provide several overload protection features. The fi rst part of this section deals with selecting resistors to set output voltage ...
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APPLICATIONS INFORMATION LT1766 AMPLIFIER Q2 V GND C divider impedance is not critical, caution 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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LT1766/LT1766-5 APPLICATIONS INFORMATION 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 ) through the inductor ...
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... After making an initial choice, consider additional factors such as core losses and second sourcing, etc. Use the experts in Linear Technology’s Applications department if you feel uncertain about the fi nal choice. They have experience with a wide range of inductor types and can tell you about the latest developments in low profi ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION 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 turn on (see Figure ...
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APPLICATIONS INFORMATION frequency decreases roughly linearly down to a limit of about 40kHz. This lower oscillator frequency during short-circuit conditions can then maintain control with the effective minimum on time recommended that for [V /(V IN OUT a ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION 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 this causes at the ...
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APPLICATIONS INFORMATION 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 above V OUT stage. However, the ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION Keep the connections from the resistors to the shutdown pin short and make sure that interplane or surface ca- pacitance to the switching nodes are minimized. If high resistor values are used, the shutdown pin should be ...
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APPLICATIONS INFORMATION MINIMIZE LT1766 C3-D1 LOOP D1 GND PLACE FEEDTHROUGH AROUND GROUND PINS (4 CORNERS) FOR GOOD THERMAL CONDUCTIVITY maximum rating. A ground plane should always be used under the switcher circuitry to prevent interplane coupling and ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION SW RISE SW FALL 2V/DIV 50ns/DIV Figure 7. Switch Node Resonance a >100MHz oscilloscope must be used, and waveforms should be observed on the leads of the package. This switch off spike will also cause the SW ...
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APPLICATIONS INFORMATION Thermal resistance for the LT1766 packages is infl uenced by the presence of internal or backside planes. SSOP (GN16) package: With a full plane under the GN16 package, thermal resistance will be about 85°C/W. TSSOP (exposed pad) package: ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION For output voltages of 5V approximately 5V. During C2 switch turn on, V will fall as the boost capacitor dicharged by the BOOST pin. In the previous BOOST Pin section, the value ...
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APPLICATIONS INFORMATION the V control voltage to the point where some sort of C cycle-skipping or odd/even cycle behavior is exhibited. In summary aware that the simultaneous requirements of high V , high I and high f may ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION When using R , the maximum value has two limitations. C First, the combination of output capacitor ESR and R may stop the loop rolling off altogether. Second, if the loop gain is not rolled off suffi ...
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APPLICATIONS INFORMATION ( )( )( ) OUT = RiseTime V BE Using the values shown in Figure 10 – • • = Rise Time The ...
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LT1766/LT1766-5 APPLICATIONS INFORMATION 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: with V = 5.5V, ...
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APPLICATIONS INFORMATION Note 44, pages 29 and 30. For our purposes here a fudge factor (ff) is used. The value for ff is about 1.2 for higher load currents and L ≥15μH. It increases to about 2.0 for smaller inductors ...
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LT1766/LT1766-5 PACKAGE DESCRIPTION 3.58 (.141) 6.60 0.10 2.94 (.116) 4.50 0.10 SEE NOTE 4 0.09 – 0.20 0.45 0.05 (.0035 – .0079) 1.05 0.10 NOTE: 0.65 BSC 1. CONTROLLING DIMENSION: MILLIMETERS RECOMMENDED SOLDER PAD LAYOUT 2. DIMENSIONS ARE IN 3. ...
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... Removed LT1766HGN from Order Information 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. LT1766/LT1766-5 ...
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... V : 0.8V 64μA, IN OUT(MIN <1μA, TSSOP20E 5.5V to 60V 1.20V 2.5mA, IN OUT(MIN 30μA, TSSOP16E 60V 100μA, 500mA Switch Current TSSOP16E 36V 0.8V 670μA, IN OUT(MIN 20μA, QFN-32, SSOP-28 SD LT/TP 0310 REV C • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2001 1766fc ...