LT4430HS6 LINER [Linear Technology], LT4430HS6 Datasheet
LT4430HS6
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LT4430HS6 Summary of contents
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FEATURES n 600mV Reference (1.25% Over Temperature) n Wide Input Supply Range 20V n Overshoot Control Function Prevents Output Overshoot on Start-Up and Short-Circuit Recovery n High Bandwidth Error Amplifi er Permits Simple Loop Frequency Compensation n Ground-Referenced ...
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... LT4430ES6 LT4430ES6#TR LT4430IS6 LT4430IS6#TR LT4430HS6 LT4430HS6#TR LT4430MPS6 LT4430MPS6#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER I Overshoot Control Charging Current OC OC Clamp Voltage OC Amplifi er Offset Voltage A Error Amplifi er Open-Loop DC Gain VOL Error Amplifi er Unity-Gain Bandwidth ...
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LT4430 TYPICAL PERFORMANCE CHARACTERISTICS Quiescent Current vs Temperature 4.0 3.5 3 20V IN 2 2.0 1.5 1.0 75 100 –75 –50 – 125 TEMPERATURE (°C) 4430 G01 FB Voltage Line Regulation ...
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TYPICAL PERFORMANCE CHARACTERISTICS Error Amplifi er Open Loop Gain and Phase vs Frequency PHASE 40 30 GAIN –10 –20 1k 10k 100k 1M 10M 50M FREQUENCY (Hz) 4430 G10 Error Amplifi er Output ...
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LT4430 TYPICAL PERFORMANCE CHARACTERISTICS Opto Driver Output Swing Low vs Temperature 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0 100 –75 –50 – 125 150 TEMPERATURE (°C) 4430 G17 Opto Driver Output Sink ...
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PIN FUNCTIONS V (Pin 1): This is the input supply that powers all in- IN ternal circuitry. The input supply range is 3V minimum to 20V maximum and the typical input quiescent current is 1.9mA. Connect a 1μF bypass capacitor ...
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LT4430 BLOCK DIAGRAM 1.1V BIAS AND V STARTUP REFERENCE IN 0.6V GENERATOR UVLO DFB – 0. 12.5μA + ERROR Q2 Q3 AMP – 12.5μ ...
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APPLICATIONS INFORMATION Block Diagram Operation A precision voltage reference, a high-bandwidth error amplifi er, an inverting opto-coupler driver and an overshoot control amplifi er comprise the LT4430. Referring to the block diagram, a start-up circuit establishes all internal current and ...
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LT4430 APPLICATIONS INFORMATION If the fault condition ceases, the output voltage increases. In response, the error amplifi er COMP pin’s voltage decreases. This action opens switch S1, deactivates the overshoot control amplifi er and allows the OC pin capacitor to ...
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APPLICATIONS INFORMATION • • 1:N Figure 1a. Typical Flyback Converter Connection Tx1 V IN • Q1 • 1:N Figure 1c. Synchronous Flyback Converter Connection V OUT C OUT 4430 F01a Figure 1b. Equivalent Flyback Converter Connection ...
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LT4430 APPLICATIONS INFORMATION The second solution is to make a preregulator as shown in Figure 2b. In this example, the bias supply equals (V – Select R2 to bias Zener diode Z1 and to supply BE base current ...
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APPLICATIONS INFORMATION Generate a bias supply for a forward converter using similar techniques to that of the fl yback converter. Figure detail the three common bias circuits for the synchronous single-switch forward converter. In the fl yback ...
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LT4430 APPLICATIONS INFORMATION Figures demonstrate bias supply circuits for the fully-synchronous push-pull topology. Biasing for full- bridge schemes is identical to the push-pull circuits with the obvious difference in the primary-side drive. In Figure 4a, the bias ...
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APPLICATIONS INFORMATION D1 R1 • ME • • Q1 • 1:N *OPTIONAL SEE TEXT MF Figure 4c. Typical Synchronous Push-Pull Converter with Preregulator Bias R2 R3* QBS LT4430 V BIAS OUT ...
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LT4430 APPLICATIONS INFORMATION Setting Output Voltage Figure 5 shows how to program the power supply output voltage with a resistor divider feedback network. Connect the top the tap point of R1/ and OUT ...
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APPLICATIONS INFORMATION In this example, the error amplifi typically a trans- conductance amplifi er with high output impedance and R dominates the impedance at the V C compensation for this feedback loop is directly affected by the output ...
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LT4430 APPLICATIONS INFORMATION In this example, the error amplifi typically a voltage error amplifi er confi gured as a transimpedance amplifi er. The opto-coupler transistor’s emitter provides feedback information directly to the FB pin and the resistor R ...
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APPLICATIONS INFORMATION Setting Overshoot Control Time Figure 7 shows how to calculate the overshoot time by connecting a capacitor from the OC pin to GND. The overshoot control time set by the formula ...
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LT4430 APPLICATIONS INFORMATION Next, increase C ’s value. Either use a capacitor substitu- OC tion box or solder each new value into the circuit. Monitor the start-up and short-circuit recovery waveforms. Note any changes. Figures illustrate what ...
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APPLICATIONS INFORMATION START-UP V OUT 5V/DIV SHORT-CIRCUIT RECOVERY V OUT 5V/DIV t = 5ms/DIV C = 100pF OC Figure 8a. Start-Up and Short-Circuit Recovery Waveforms START-UP V OUT 5V/DIV SHORT-CIRCUIT RECOVERY V OUT 5V/DIV t = 5ms/DIV C = 0.022μF ...
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LT4430 TYPICAL APPLICATIONS 22 4430fb ...
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TYPICAL APPLICATIONS • • • • • • • • (%) EFFICIENCY LT4430 4430fb 23 ...
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LT4430 PACKAGE DESCRIPTION 0.62 0.95 MAX REF 3.85 MAX 2.62 REF RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.20 BSC DATUM ‘A’ 0.30 – 0.50 REF NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE ...
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REVISION HISTORY (Revision history begins at Rev B) REV DATE DESCRIPTION B 5/11 H-Grade and MP-Grade parts added. Refl ected throughout the data sheet. Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility ...
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LT4430 TYPICAL APPLICATION 5V, 2A Isolated Flyback Telecom Converter Start-Up Waveforms with and without Overshoot Control Implemented 36V TO 72V 220k C1 Q2 1μF MMBTA42 100V D1 8.5V PDZ-9.1B 9.1V D2 –V IN BAS516 I /SHDN TH ...