AAT1121IES-0.6-T1 Advanced Analog Technology, Inc., AAT1121IES-0.6-T1 Datasheet
AAT1121IES-0.6-T1
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AAT1121IES-0.6-T1 Summary of contents
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General Description The AAT1121 SwitchReg is a 1.5MHz step-down converter with an input voltage range of 2.7V to 5.5V and output as low as 0.6V. Its low supply current, small size, and high switching frequency make the AAT1121 the ideal ...
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Pin Descriptions Pin # Symbol Function 1 VP Input power pin; connected to the source of the P-channel MOSFET. Connect to the input capacitor. 2 VIN Input bias voltage for the converter. 3 GND Non-power signal ground pin ...
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Absolute Maximum Ratings Symbol Description V Input Voltage and Bias Power to GND GND GND OUT GND EN T Operating Junction Temperature Range J T Maximum Soldering Temperature (at ...
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Electrical Characteristics V = 3.6V -40°C to +85°C, unless otherwise noted; typical values are Symbol Description V Input Voltage IN V UVLO Threshold UVLO V Output Voltage Tolerance OUT V Output Voltage Range OUT I ...
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Typical Characteristics Efficiency vs. Load (V = 1.2V 1.5µH) OUT 100 Output ...
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Typical Characteristics Soft Start (V = 3.6V 1.8V; IN OUT I = 250mA 100pF) OUT FF 5.0 V 4.0 EN 3.0 2.0 1.0 0 Time (100µs/div) Output Voltage Error vs. Temperature (V ...
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Typical Characteristics P-Channel R vs. Input Voltage DS(ON) 1000 900 120°C 100°C 85°C 800 700 600 25°C 500 400 300 2.5 3.0 3.5 4.0 4.5 Input Voltage (V) Load Transient Response (10mA to 250mA 3.6V ...
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Typical Characteristics Output Ripple (V = 3.6V 1.8V OUT OUT - Time (2µs/div) 8 1.5MHz, 250mA Step-Down Converter = 1mA 0.04 -20 0.03 0.02 0.01 0.00 ...
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Functional Block Diagram FB Voltage Reference EN INPUT Functional Description The AAT1121 is a high performance 250mA, 1.5MHz monolithic step-down converter designed to operate with an input voltage range of 2.7V to 5.5V. The converter operates at 1.5MHz, which minimizes ...
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Control Loop The AAT1121 is a 250mA 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- tection. A fixed slope compensation signal is added ...
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Output Voltage (V) 1.0 1.2 1.5 1.8 2.5 3.0 3.3 Table 1: Inductor Values. The 3.0µH CDRH2D09 series inductor selected from Sumida has a 150mΩ DCR and a 470mA DC current rating. At full load, the inductor DC loss is ...
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In applications where the input power source lead inductance cannot be reduced to a level that does not affect the converter performance, a high ESR tantalum or aluminum electrolytic should be placed in parallel with the low ESR, ESL bypass ...
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Thermal Calculations There are three types of losses associated with the AAT1121 step-down converter: switching loss- es, conduction losses, and quiescent current loss- es. Conduction losses are associated with the R characteristics of the power output switch- DS(ON) ing devices. ...
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Layout The suggested PCB layout for the AAT1121 is shown in Figures 2, 3, and 4. The following guide- lines should be used to help ensure a proper layout. 1. The input capacitor (C1) should connect as closely as possible ...
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Step-Down Converter Design Example Specifications = 1.8V @ 250mA, Pulsed Load Δ 2.7V to 4.2V (3.6V nominal 1.5MHz 85°C AMB 1.8V Output Inductor µsec µsec L1 = 1.67 ⋅ V ...
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Input Capacitor Input Ripple V = 25mV ⎛ V ⎞ ⎛ 25mV - ESR · 4 · ⎝ I ⎠ ⎝ 0. 0.1Arms RMS 2 ...
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Output Voltage V (V) OUT 0.6 2 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.8 1.85 2.0 2.5 3.3 Manufacturer Part Number Sumida CDRH2D09-1R5 Sumida CDRH2D09-2R2 Sumida CDRH2D09-2R5 Sumida CDRH2D09-3R0 Sumida CDRH2D09-3R9 Sumida CDRH2D09-4R7 Sumida CDRH2D09-5R6 Sumida CDRH2D11-1R5 Sumida ...
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Manufacturer Part Number Murata GRM118R60J475KE19B Murata GRM188R60J106ME47D 18 1.5MHz, 250mA Step-Down Converter Value (µF) 4.7 10 Table 5: Surface Mount Capacitors. AAT1121 Voltage Temp. Case Rating Co. Size 6.3 X5R 0603 6.3 X5R 0603 1121.2007.03.1.2 ...
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... Step-Down Converter Package Marking 1 TDFN22-8 RWXYY RWXYY TDFN22-8 0.600 ± 0.050 Detail "A" Bottom View AAT1121 Part Number (Tape and Reel) AAT1121IPS-0.6-T1 AAT1121IES-0.6-T1 0.350 ± 0.100 0.1 REF (optional) C0.3 Pin 1 Indicator (optional) Detail "A" ...
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Index Area 2.00 ± 0.05 (D/2 x E/2) Top View 0.05 ± 0.05 Side View All dimensions in millimeters. © Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an ...