AAT1147 AAT, AAT1147 Datasheet
AAT1147
Related parts for AAT1147
AAT1147 Summary of contents
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... fixed frequency 1.4MHz step-down converter with an input volt- age range of 2.7V to 5.5V and output voltage as low as 0.6V. The AAT1147 is optimized for low noise portable applications, reacts quickly to load variations, and reaches peak efficiency at heavy load. The AAT1147 output voltage is programmable with external feedback resistors ...
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Pin Descriptions Pin # Symbol Function 1 EN Enable pin. 2 OUT Feedback input pin. This pin is connected to an external resistive divider for an adjustable output. 3 VIN Input supply voltage for the converter Switching node. ...
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Absolute Maximum Ratings Symbol Description V Input Voltage to GND GND LX V OUT to GND OUT GND EN T Operating Junction Temperature Range J T Maximum Soldering Temperature (at leads, 10 sec) ...
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... V Enable Threshold High EN(H) I Input Low Current EN 1. The AAT1147 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. 4 High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter 1 = 25°C, V ...
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Typical Characteristics Efficiency vs. Load (V = 3.3V 6.8µH) OUT 100 Output Current (mA) Efficiency vs. Load (V = ...
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Typical Characteristics Line Regulation (V = 3.3V) OUT 0.5 0.4 0 10mA I = 1mA OUT OUT 0.2 0.1 0 -0.1 -0 400mA -0.3 OUT -0.4 -0.5 3.0 3.2 3.4 3.6 3.8 4.0 4.2 Input Voltage ...
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Typical Characteristics No-Load Quiescent Current vs. Input Voltage 220 210 200 25°C 190 85°C 180 170 160 150 140 130 120 2.5 3.0 3.5 4.0 Input Voltage (V) Line Transient Response (40mA to 400mA 3.6V ...
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... Voltage Reference EN INPUT Functional Description The AAT1147 is a high performance 400mA 1.4MHz monolithic step-down converter. It has been designed with the goal of minimizing external component size and optimizing efficiency at heavy load. Apart from the small bypass input capacitor, only a small L-C filter is required at the output. ...
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... V Figure 1: Enhanced Transient Response Schematic. Control Loop The AAT1147 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- tection. A fixed slope compensation signal is added to the sensed current to maintain stability for duty cycles greater than 50% ...
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... The internal slope compensation for the AAT1147 is 0.24A/µsec. This equates to a slope compensation that is 75% of the inductor current down slope for a 1.5V output and 4.7µH inductor. ...
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... The input capacitor provides a low impedance loop for the edges of pulsed current drawn by the AAT1147. Low ESR/ESL X7R and X5R ceramic capacitors are ideal for this function. To minimize stray inductance, the capacitor should be placed as closely as possible to the IC. This keeps the high frequency content of the input current localized, minimizing EMI and input voltage ripple ...
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... Dissipation due to the RMS current in the ceramic output capacitor ESR is typically minimal, resulting in less than a few degrees rise in hot-spot temperature. Output Resistor Selection The output voltage of the AAT1147 0.6V version can be externally programmed. Resistors R1 and R2 of Figure 5 program the output to regulate at a voltage 12 ...
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... The AAT1147, combined with an external feedfor- ward capacitor (C4 in Figure 1), delivers enhanced transient response for extreme pulsed load appli- cations. The addition of the feedforward capacitor typically requires a larger output capacitor C1 for stability 59kΩ Ω R1 (kΩ Ω (V) OUT 0.8 19.6 0.9 29.4 1.0 39.2 1.1 49.9 1.2 59.0 1.3 68.1 1.4 78.7 1.5 88.7 1.8 118 1 ...
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... · Θ J(MAX) TOTAL JA Layout The suggested PCB layout for the AAT1147 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 (C2) should connect as closely as possible to V (Pin 3) and PGND IN (Pins 6-8 and L1 should be connected as closely as possible ...
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Step-Down Converter Design Example Specifications V = 1.8V @ 400mA (adjustable using 0.6V version), Pulsed Load Δ 2.7V to 4.2V (3.6V nominal 1.4MHz 85°C AMB 1.8V Output Inductor μsec μsec L1 ...
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... V ⎞ ⎛ 25mV - ESR · 4 · ⎝ I ⎠ ⎝ 0. 0.2Arms RMS esr · 5mΩ · (0.2A 0.2mW RMS AAT1147 Losses I 2 · (R · DSON(H) O DSON( TOTAL · F · · 0.4 2 · (0.725 Ω · 1.8V + 0.7Ω · [4.2V - 1.8V ...
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Adjustable Version (0.6V device) V (V) OUT 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 CDRH3D16-2R2 Sumida CDRH3D16-4R7 Sumida CDRH3D16-6R8 MuRata LQH2MCN4R7M02 MuRata LQH32CN4R7M23 Coilcraft LPO3310-472 Coiltronics SD3118-4R7 Coiltronics SD3118-6R8 Coiltronics ...
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Manufacturer Part Number MuRata GRM219R61A475KE19 MuRata GRM21BR60J106KE19 MuRata GRM21BR60J226ME39 18 High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter Value 4.7µF 10µF 22µF Table 5: Surface Mount Capacitors. Voltage Temp. Co. Case 10V X5R 0805 6.3V X5R 0805 6.3V X5R ...
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... Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 1147.2006.05.1.0 High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter Marking Part Number (Tape and Reel) 1 SCXYY SC70JW-8 0.225 ± 0.075 0.100 0.45 ± 0.10 2.10 ± 0.30 2 AAT1147IJS-0.6-T1 0.048REF 4° ± 4° 19 ...