LTC3550EDHC#PBF Linear Technology, LTC3550EDHC#PBF Datasheet
LTC3550EDHC#PBF
Specifications of LTC3550EDHC#PBF
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LTC3550EDHC#PBF Summary of contents
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... The DC/DC converter switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. *Protected by U.S. patents, includng 6522118, 6700364, 6580258, 5481178, 6304066, 6127815, 6498466, 6611131 2.2µ ...
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LTC3550 ABSOLUTE AXI U RATI GS (Note 1) DCIN, USBIN .............................................. –0.3V to 10V EN, ⎯ C ⎯ H ⎯ R ⎯ ⎯ P ⎯ W ⎯ HPWR ............................ –0.3V to 10V BAT, ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Battery Charger I DCIN Supply Current DCIN Charge Mode (Note 5) Standby Mode Shutdown Mode I USBIN Supply Current USBIN Charge Mode (Note 6) Standby Mode Shutdown Mode ...
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LTC3550 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER I V Supply Current S CC Active Mode Sleep Mode Shutdown f Oscillator Frequency OSC P-Channel FET PFET DS(ON N-Channel FET ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Regulated Charger Output (Float) Voltage vs Charge Current 4. DCIN USBIN 4.24 4.22 4.20 4.18 4. 1.25k IDC IDC IUSB 4.14 ...
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LTC3550 W U TYPICAL PERFOR A CE CHARACTERISTICS Charge Current vs Ambient Temperature 1000 ONSET OF THERMAL REGULATION 800 R = 1.25k IDC 600 IDC IUSB 400 200 DCIN USBIN ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS HPWR Pin Pull-Down Resistance vs Temperature 2.8 2.6 2.4 2.2 2.0 1.8 1.6 50 –50 – TEMPERATURE (°C) 3550 G45 Recharge Threshold Voltage vs Temperature 4.16 4.14 4. ...
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LTC3550 W U TYPICAL PERFOR A CE CHARACTERISTICS Buck Regulator Effi ciency vs Output Current 100 V = 2.5V OUT ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Switch Leakage Current vs Temperature 300 V = 5.5V CC RUN = 0V 250 200 150 100 MAIN SWITCH 50 SYNCHRONOUS SWITCH 0 50 –50 – TEMPERATURE (°C) Burst Mode Operation ...
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LTC3550 CTIO S USBIN (Pin 1): USB Input Supply Pin. Provides power to the battery charger. The maximum supply current is 650mA. This should be bypassed with a 1µF capacitor. IUSB (Pin 2): USB Charge ...
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CTIO S DCIN (Pin 16): Wall Adapter Input Supply Pin. Provides power to the battery charger. The maximum supply current is 950mA. This should be bypassed with a 1µF capacitor. W BLOCK DIAGRA DCIN 16 ...
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LTC3550 U OPERATIO The LTC3550 consists of two main blocks: a lithium-ion battery charger and a high-effi ciency buck converter that can be powered from the battery. The charger is designed to effi ciently manage charging of a single-cell lithium-ion ...
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... The LTC3550 buck regulator is capable of Burst Mode operation in which the internal power MOSFETs operate intermittently based on load current demand. Burst Mode is a registered trademark of Linear Technology Corporation. In Burst Mode operation, the peak current of the inductor is set to approximately 200mA regardless of the output load. ...
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LTC3550 U OPERATIO Battery Charger Power Source Selection The LTC3550 can charge a battery from either the wall adapter input or the USB port input. The charger automati- cally senses the presence of voltage at each input. If both power ...
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U U APPLICATIO S I FOR ATIO Figure 2 shows the basic LTC3550 application circuit. External component selection is driven by the charging requirements and the buck regulator load requirements. SW LTC3550 WALL DCIN V FB ADAPTER RUN USB USBIN ...
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LTC3550 U U APPLICATIO S I FOR ATIO Buck Regulator Inductor Selection For most applications, the value of the inductor will fall in the range of 1µH to 4.7µH. Its value is chosen based on the desired inductor ripple current. ...
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U U APPLICATIO S I FOR ATIO where f = operating frequency, C OUT and ΔI = ripple current in the inductor. For a fi xed output L voltage, the output ripple voltage is highest at maximum input voltage since ...
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LTC3550 U U APPLICATIO S I FOR ATIO switch gate charge currents. The gate charge current results from switching the gate capacitance of the internal power MOSFET switches. Each time the gate is switched from high to low to high ...
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U U APPLICATIO S I FOR ATIO For simplicity, assume the buck regulator is disabled and dissipates no power (P = 0). For a properly soldered D(BUCK) DHC16 package, the thermal resistance (θ Thus, the ambient temperature at which the ...
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... Q characteristics of ceramic capacitors can cause substantial ringing which could exceed the maximum voltage ratings and damage the LTC3550. Refer to Linear Technology Application Note 88, entitled “Ceramic Input Capacitors Can Cause Overvoltage Transients” for a detailed discussion of this problem. The long cable lengths of most wall adapters and USB cables makes them especially susceptible to this problem ...
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U U APPLICATIO S I FOR ATIO C F VIA TO V OUT R2 VIA TO R1 GND 1. The power traces, consisting of the GND trace, the SW trace and the V trace should be kept short, direct CC ...
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LTC3550 U U APPLICATIO S I FOR ATIO is a maximum of 600mA but most of the time it will be in standby mode, requiring only 2mA. Effi ciency at both low and high load currents is important. With this ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 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. U DHC Package 16-Lead Plastic DFN (5mm × ...
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... Dual Input Charger Plus Step-Down Converter with Wall Adapter PowerPath USB POWER 1µF 2.1k 1.24k PowerPath is a trademark of Linear Technology Corporation RELATED PARTS PART NUMBER DESCRIPTION LTC3406/LTC3406B 1.5MHz, 600mA Synchronous Step-Down DC/DC Converter in ThinSOT LTC3455 Dual DC/DC Converter with USB Power Management and Li-Ion Battery Charger LTC3456 ...