AAT1143IJS-1.8-T1 AnalogicTech, AAT1143IJS-1.8-T1 Datasheet

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... General Description The AAT1143 SwitchReg™ member of AnalogicTech's Total Power Management IC™ (TPMIC™) product family 1MHz step-down converter with an input voltage range of 2.7V to 5.5V and output as low as 0.6V. Its low supply cur- rent, small size, and high switching frequency make the AAT1143 the ideal choice for portable applications ...

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Pin Descriptions Pin # Symbol Function 1 EN Enable pin. 2 OUT Feedback input pin. This pin is connected either directly to the converter output external resistive divider for an adjustable output. 3 VIN Input supply voltage ...

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Absolute Maximum Ratings Symbol Description V Input Voltage GND GND OUT to GND OUT GND EN T Operating Junction Temperature Range J T Maximum Soldering Temperature (at leads, 10 sec) ...

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... EN 1. The AAT1143 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls. 2. For adjustable version with higher than 2.5V output, please consult your AnalogicTech representative. 4 1MHz 400mA Step-Down Converter 1 = 25° ...

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Typical Characteristics Efficiency vs. Load = 2.5V 4.7µ µ OUT 100 Output Current (mA) Efficiency vs. Load ...

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Typical Characteristics Switching Frequency vs. Temperature (V = 3.6V 1.5V 0.20 0.10 0.00 -0.10 -0.20 -40 - Temperature (° ° C) P-Channel R vs. Input Voltage DS(ON) 750 700 650 120°C 100°C 600 ...

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Typical Characteristics Load Transient Response = 1.8V 4.7µ µ F) (30mA - 300mA 3.6V OUT 2.0 1.9 1.8 300mA 1.7 1.6 30mA 1.5 1.4 1.3 1.2 Time (25µs/div) Line Regulation (V = 1.8V) OUT ...

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Functional Block Diagram Voltage Reference INPUT EN Note: For adjustable version, the internal feedback divider is omitted and the FB pin is tied directly to the internal error amplifier. Functional Description The AAT1143 is a high performance 400mA 1MHz monolithic ...

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V Figure 1: Enhanced Transient Response Schematic. Control Loop The AAT1143 is a peak current mode step-down converter. The current through the P-channel MOSFET (high side) is sensed for current loop control, as well as short circuit and overload pro- ...

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Applications Information Inductor Selection The step-down converter uses peak current mode control with slope compensation to maintain stability for duty cycles greater than 50%. The output induc- tor value must be selected so the inductor current down slope meets the ...

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The maximum input capacitor RMS current is: ⎛ · · RMS O ⎝ The input capacitor RMS ripple current varies with the input and output voltage and ...

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Figure 2: AAT1143 Evaluation Board Top Side. The maximum output capacitor RMS ripple current is given by · (V OUT IN(MAX · RMS(MAX) L · F · · 3 Dissipation due to the RMS ...

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The adjustable version of the AAT1143, combined with an external feedforward capacitor (C4 in Figure 1), delivers enhanced transient response for extreme pulsed load applications. The addition of the feedforward capacitor typically requires a larg- er output capacitor C1 for ...

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For the condition where the step-down converter is in dropout at 100% duty cycle, the total device dis- sipation reduces to · TOTAL O DSON(HS) Since R , quiescent current, and switching DS(ON) ...

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Step-Down Converter Design Example Specifications = 1.8V @ 400mA (adjustable using 0.6V version), Pulsed Load ∆ 2.7V to 4.2V (3.6V nominal 1.0MHz 85°C AMB 1.8V Output Inductor µsec µsec ⋅ ...

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Input Capacitor Input Ripple V = 25mV ⎛ ⎞ ⎛ V 25mV PP - ESR · 4 · F ⎝ ⎠ ⎝ 0. 0.2Arms RMS 2 ...

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V (V) OUT Adjustable Version (0.6V device) 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.8 1.85 2.0 2.5 V (V) OUT Fixed Version 0.6-3.3V Table 3: Evaluation Board Component Values. Manufacturer Part Number Sumida CDRH3D16-4R7 Sumida CDRH3D16-100 MuRata LQH32CN4R7M23 ...

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Manufacturer Part Number MuRata GRM21BR61A475KA73L MuRata GRM18BR60J475KE19D MuRata GRM21BR60J106KE19 MuRata GRM21BR60J226ME39 18 1MHz 400mA Step-Down Converter Value 4.7µF 4.7µF 10µF 22µF Table 5: Surface Mount Capacitors. AAT1143 Voltage Temp. Co. Case 10V X5R 0805 6.3V X5R 0603 6.3V X5R 0805 ...

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... Sample stock is generally held on part numbers listed in BOLD. 1143.2005.09.1.7 1MHz 400mA Step-Down Converter Marking 2 NUXYY PBXYY NXXYY PYXYY OKXYY OYXYY SC70JW-8 0.225 ± 0.075 2.00 ± 0.20 0.100 AAT1143 Part Number (Tape and Reel) AAT1143IJS-0.6-T1 AAT1143IJS-1.2-T1 AAT1143IJS-1.5-T1 AAT1143IJS-1.6-T1 AAT1143IJS-1.8-T1 AAT1143IJS-2.5-T1 AAT1143IJS-3.3-T1 0.048REF 0.45 ± 0.10 4° ± 4° 2.10 ± 0. ...

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... AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’ ...