LTC3550EDHC-1#TR Linear Technology, LTC3550EDHC-1#TR Datasheet
LTC3550EDHC-1#TR
Specifications of LTC3550EDHC-1#TR
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LTC3550EDHC-1#TR Summary of contents
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... The switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. , 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, includng 6522118, 6700364, 6580258, 5481178, 6304066, 6127815, 6498466, 6611131 2.2µ ...
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... PLASTIC DFN T EXPOSED PAD IS GROUND (PIN 17) ORDER PART NUMBER LTC3550EDHC-1 Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER V V – V Lockout Threshold Voltage V ASD-DC DCIN BAT V V – V Lockout Threshold ASD-USB USBIN BAT Voltage Battery Charger I DCIN Supply Current DCIN ...
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LTC3550-1 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER f Oscillator Frequency OSC P-Channel FET PFET DS(ON N-Channel FET NFET DS(ON Leakage Current LSW Note 1: Stresses beyond ...
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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 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 TYPICAL PERFOR A CE CHARACTERISTICS Undervoltage Lockout Threshold vs Temperature 4.25 4.20 DCIN UVLO 4.15 4.10 4.05 4.00 USBIN UVLO 3.95 3.90 3.85 75 –50 – TEMPERATURE (°C) 3550-1 G19 Charge Current During Turn-On and Turn-Off ...
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LTC3550 TYPICAL PERFOR A CE CHARACTERISTICS Buck Regulator Output Voltage vs Load Current 1. 3.6V CC 1.89 1.88 1.87 1.86 1.85 0 100 200 300 400 500 600 700 800 I (mA) LOAD 35501 G28 Buck ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Start-Up from Shutdown RUN 2V/DIV V OUT 1V/DIV I L 500mA/DIV 35501 G36 V = 3.6V 40µs/DIV 600mA LOAD Load Step V OUT 100mV/DIV AC COUPLED I L 500mA/DIV V ...
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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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LTC3550-1 U OPERATIO The LTC3550-1 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 output voltage will Burst Mode is a registered trademark of Linear Technology Corporation. then be determined by the input voltage minus the voltage drop across the P-channel MOSFET and the inductor. ...
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LTC3550-1 U OPERATIO The power supply status output ( ⎯ P ⎯ W ⎯ has two states: pull- down and high impedance. The pull-down state indicates that power is present at either DCIN or USBIN power ...
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U U APPLICATIO S I FOR ATIO Figure 2 shows the basic LTC3550-1 application circuit. External component selection is driven by the charging requirements and the buck regulator load requirements. LTC3550-1 RUN SW WALL ADAPTER DCIN V OUT USB USBIN ...
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LTC3550 APPLICATIO S I FOR ATIO The DC current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation. Thus, a 720mA rated inductor should ...
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U U APPLICATIO S I FOR ATIO Using Ceramic Input and Output Capacitors Higher capacitance values, lower cost ceramic capacitors are now becoming available in smaller case sizes. Their high ripple current, high voltage rating and low ESR make them ...
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LTC3550 APPLICATIO S I FOR ATIO Thermal Considerations The battery charger’s thermal regulation feature and the buck regulator’s high effi ciency make it unlikely that enough power is dissipated to exceed the LTC3550-1 maximum junction temperature. Nevertheless, it ...
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... Q characteristics of ceramic capacitors can cause substantial ringing which could exceed the maximum voltage ratings and damage the LTC3550-1. Refer to Linear Technology Application Note 88, entitled “Ceramic Input Capacitors Can Cause Overvoltage Transients” for a detailed discussion of this problem ...
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LTC3550 APPLICATIO S I FOR ATIO the bottom trace, a 1Ω resistor is added in series with the 4.7µF capacitor to locally bypass the 5V input. This trace shows the clean response resulting from the addition of the ...
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U U APPLICATIO S I FOR ATIO and high load currents is important. With this information we can calculate L using Equation (1), ⎛ ⎞ OUT OUT ∆ = − I • 1 ⎝ ⎜ ⎠ ⎟ L ...
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LTC3550 APPLICATIO S I FOR ATIO WALL ADAPTER USB POWER 1µF * MURATA LQH32CN2R2M33 ** TAIYO YUDEN JMK316BJ106ML † TAIYO YUDEN LMK212BJ475MG U TYPICAL APPLICATIO S Full Featured Dual Input Charger Plus Step-Down Converter WALL ADAPTER USB POWER ...
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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 Standalone Li-Ion Battery Charger LTC4076 Dual Input Standalone Li-Ion Battery Charger LTC4077 Dual Input Standalone Li-Ion Battery Charger PowerPath and ThinSOT are trademarks of Linear Technology Corporation. Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● LTC3550-1 DCIN 1µ ...