AAT1154IAS-1.0-T1 Analogic Tech, AAT1154IAS-1.0-T1 Datasheet

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SwitchReg TM General Description The AAT1154 SwitchReg is a step-down switching con- verter ideal for applications where high efficiency, small size, and low ripple are critical. Able to deliver 3A with an internal power MOSFET, the current-mode controlled IC provides ...

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SwitchReg SwitchReg TM TM Pin Descriptions Pin # Symbol Function Feedback input pin. This pin must be connected to the converter output used to set the converter 1 FB output to regulate to the desired value. 2 GND ...

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SwitchReg SwitchReg TM TM Absolute Maximum Ratings T = 25°C, unless otherwise noted. A Symbol Description VCC GND GND GND GND EN ...

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SwitchReg SwitchReg TM TM Electrical Characteristics 5V -40°C to +85°C, unless otherwise noted. Typical values are Symbol Description V Input Voltage Range IN V Output Voltage ...

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SwitchReg SwitchReg TM TM Typical Characteristics Efficiency vs. Load Current ( 3.3V) IN OUT 100 0.01 0.1 1 Output Current (A) Oscillator Frequency Variation vs. Supply Voltage 0.5 ...

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SwitchReg SwitchReg TM TM Typical Characteristics Output Voltage vs. Temperature (I = 2A) OUT 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 - Temperature (° ° C) Over-Temperature Current vs. Input Voltage (V = 3.3V) OUT 3.6 3.4 ...

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SwitchReg SwitchReg TM TM Typical Characteristics Inrush and Output Overshoot Characteristics (3A Load) 14 Inductor Current Input 4 2 Output 0.4 0.8 1.2 Time (ms) Output Ripple (I = 3.0A 3.3V; ...

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SwitchReg SwitchReg TM TM Typical Characteristics Loop Crossover Gain and Phase 16 120μF 6.3V Tantalum 12 Vishay P/N 594D127X96R3C2T 8 Phase Gain -8 -12 -16 10000 Frequency (Hz) Transient Response ( 3.0A ...

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SwitchReg TM Functional Block Diagram VCC REF FB GND Applications Information Main Control Loop The AAT1154 is a peak current mode step-down con- verter. The inner wide bandwidth loop controls the inductor peak current. The inductor current is sensed as ...

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SwitchReg TM addition, the low pass filter R1 and C3 (shown in Figure 1) filters noise associated with the power switching. Current Limit and Over-Temperature Protection Over-temperature and current limit circuitry protects the AAT1154 and the external Schottky diode during ...

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SwitchReg TM Schottky Freewheeling Diode The Schottky average current is the load current multi- plied by one minus the duty cycle. For V at 3.3V, the average diode current is: ⎛ V ⎞ ⎛ O · · ...

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SwitchReg TM Figure 2: AAT1154 Fixed Output Top Side Layout. Layout Figures 2 and 3 display the suggested PCB layout for the fixed output AAT1154. The following guidelines should be used to help ensure a proper layout. 1. The connection ...

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SwitchReg TM Design Example (See Figures 1 and 4 for reference OUT I 30% of Full Load at Max V RIPPLE IN V 3.3V OUT V 5V ± 1MHz S T 70°C MAX Inductor Selection ⎛ ...

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SwitchReg TM The ESR requirement for a tantalum capacitor can be estimated by: V 100 mV ≤ RIPPLE ESR = = 121 mΩ Δ I 0.82A · (V OUT · RMS ...

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SwitchReg SwitchReg TM TM Figure 6: Evaluation Board Adjustable Output Top Side Layout. Part Number Manufacturer C4532X5ROJ107M GRM43-2 X5R 107M 6.3 Murata GRM43-2 X5R 476K 6.3 Murata GRM42-6 X5R 106K 6.3 Murata 594D127X_6R3C2T Vishay 595D107X0016C Vishay Part Number Manufacturer CDRH6D38-4763-T055 ...

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... Specifi c testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders 1MHz 3A Step-Down DC/DC Converter 1MHz 3A Step-Down DC/DC Converter Marking Part Number (Tape and Reel) 115410 AAT1154IAS-1.0-T1 115418 AAT1154IAS-1.8-T1 115425 AAT1154IAS-2.5-T1 115433 AAT1154IAS-3.3-T1 SOP-8 0.375 ± 0.125 45° ...