AAT1123 AAT, AAT1123 Datasheet
AAT1123
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AAT1123 Summary of contents
Page 1
... AAT1123 the ideal choice for portable applications. The AAT1123 is available in either a fixed version with internal feedback or a programmable version with external feedback resistors. It can deliver up to 600mA of load current while maintaining a low 25µ ...
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... MOSFETs. 5 AGND Non-power signal ground pin PGND Main power ground return pin. Connect to the output and input capacitor return. Pin Configuration 2 1MHz Step-Down Converter SC70JW-8 (Top View) EN PGND 8 1 OUT PGND 2 7 VIN PGND AGND 4 5 AAT1123 1123.2006.05.1.5 ...
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... Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi- tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Mounted on an FR4 board. 1123.2006.05.1.5 1MHz Step-Down Converter 1 (SC70JW-8) 2 AAT1123 Value Units 6 ...
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... Enable Threshold Low EN(L) V Enable Threshold High EN(H) I Input Low Current EN 1. The AAT1123 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 1MHz Step-Down Converter 1 = 25° Conditions ...
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... V IN 2.0 1.0 0.0 V -1.0 IN -2.0 -3.0 100 1000 0.1 3.0 V 2.0 IN 1.0 0.0 V -1.0 IN -2.0 -3.0 100 1000 0.1 AAT1123 1MHz Step-Down Converter DC Regulation = 3.3V 10μ μ OUT 100 Output Current (mA) DC Regulation = 2.5V 10μ μ OUT = 100 Output Current (mA) DC Regulation = 1.5V 4.7μ μ OUT = 4 ...
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... Quiescent Current vs. Input Voltage 35 85°C 30 25° -40° 100 2.5 3.0 N-Channel R 750 700 650 600 550 500 450 400 25°C 350 300 2.5 3.0 5.0 5.5 6.0 AAT1123 (V = 3.6V 2.5V 100 Temperature (° ° 1.8V) O 3.5 4.0 4.5 5.0 5.5 6.0 Input Voltage (V) vs. Input Voltage DS(ON) 120°C 100°C 85°C 3.5 4.0 4.5 5 ...
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... Load Transient Response (30mA - 300mA 2.65 1.5 2.55 1.3 1.1 2.45 0.9 2.35 0.7 0.5 2.25 0.3 2.15 0.1 -0.1 2.05 Time (25μs/div) Line Regulation 2 7.0 6.5 1.5 6 600mA 1 OUT 5.5 0.5 5.0 4.5 0 4.0 -0.5 3.5 -1 3.0 2.5 3 3.5 Input Voltage (V) Soft Start (V = 3.6V 4.0 0.9 3.0 0.8 2.0 0.7 1.0 0.6 0.0 0.5 -1.0 0.4 -2.0 0.3 -3.0 0.2 -4.0 0.1 Time (50μs/div) AAT1123 = 2.5V 22μ μ 3.6V; V OUT 1.5 1.3 1.1 300mA 0.9 30mA 0.7 0.5 0.3 0.1 -0 1.5V) OUT I = 100mA OUT I = 10mA OUT 4 4 1.5V 4.7μ μ H) OUT 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 -0.5 7 ...
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... 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 AAT1123 is a high performance 600mA 1MHz monolithic step-down converter. It has been designed with the goal of minimizing external com- ponent size and optimizing efficiency over the com- plete load range ...
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... Soft Start / Enable Soft start limits the current surge seen at the input and eliminates output voltage overshoot. When pulled low, the enable input forces the AAT1123 into a low-power, non-switching state. The total 1123.2006.05.1 ...
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... The internal slope compensation for the adjustable and low-voltage fixed versions of the AAT1123 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. 0.75 ⋅ V 0.75 ⋅ ...
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... The input capacitor provides a low impedance loop for the edges of pulsed current drawn by the AAT1123. Low ESR/ESL X7R and X5R ceramic capacitors are ideal for this function. To minimize stray inductance, the capacitor should be placed 1 as closely as possible to the IC ...
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... R2 set to either 59kΩ for good noise immunity or 221kΩ for reduced no load input current. ⎛ ⎝ The adjustable version of the AAT1123, combined with an external feedforward capacitor (C4 in Figure 1), delivers enhanced transient response for S extreme pulsed load applications. The addition of the feedforward capacitor typically requires a larg- er output capacitor C1 for stability ...
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... V OUT 22μF GND GND2 Figure 5: AAT1123 Adjustable Evaluation Board Schematic. 1123.2006.05.1.5 Conduction losses are associated with the 221kΩ Ω characteristics of the power output switching R1 (kΩ Ω ) devices. Switching losses are dominated by the gate charge of the power output switching devices ...
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... J(MAX) TOTAL JA Layout The suggested PCB layout for the AAT1123 is shown in Figures 2, 3, and 4. The following guide- lines should be used to help ensure a proper layout. 14 1MHz Step-Down Converter 1. The input capacitor (C2) should connect as closely as possible to V (Pins 6-8 and L1 should be connected as closely as possible ...
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... RMS L1 · F · · 3 IN(MAX esr · 5mΩ · (63mA) esr RMS 1123.2006.05.1.5 (see Table 1) ⎛ ⎞ 1.8V ⋅ 218mA ⎝ ⎠ 4.2V = 18.0μF 1 1.8V · (4.2V - 1.8V) · = 63mArms = 4.7μH · 1.0MHz · 4.2V 2 · 20μW AAT1123 1MHz Step-Down Converter = 300mA LOAD 15 ...
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... PP - ESR · 4 · F ⎝ ⎠ ⎝ 0. 0.2Arms RMS esr · 5mΩ · (0.2A) = 0.2mW RMS AAT1123 Losses 2 I · (R · DSON(HS) O DSON(LS TOTAL · F · · · (0.725 Ω · 1.8V + 0.7Ω · [4.2V - 1.8V ...
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... R1 (kΩ Ω Not Used 0 Inductance Max DC (µH) Current (A) 4.7 0.90 10 0.84 4.7 0.65 4.7 0.65 4.7 1.10 4.7 0.80 4.7 1.53 4.7 1.30 4.7 0.98 4.7 1.77 AAT1123 1MHz Step-Down Converter L1 (µ 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4 (µH) 4.7 DCR Size (mm) (Ω Ω ) LxWxH Type 0.11 4.0x4.0x1.8 Shielded 0.23 4.0x4.0x1.8 Shielded 0.15 2.5x3.2x2.0 Non-Shielded 0.15 2.5x3.2x1.55 Non-Shielded ...
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... Manufacturer Part Number MuRata GRM21BR60J226ME39 TDK C2012X5R0J226K Taiyo-Yuden JMK212BJ226KL 18 1MHz Step-Down Converter Value 22µF 22µF 22µF Table 5: Surface Mount Capacitors. AAT1123 Voltage Temp. Co. Case 6.3V X5R 0805 6.3V X5R 0805 6.3V X5R 0805 1123.2006.05.1.5 ...
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... Contact Sales for other voltage options. 2. XYY = assembly and date code. 3. Sample stock is generally held on part numbers listed in BOLD. 1123.2006.05.1.5 1MHz Step-Down Converter Marking 2 PMXYY SC70JW-8 0.225 ± 0.075 0.100 0.45 ± 0.10 2.10 ± 0.30 AAT1123 Part Number (Tape and Reel) 3 AAT1123IJS-0.6-T1 0.048REF 4° ± 4° 19 ...
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... AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are regis- tered trademarks or trademarks of their respective holders. Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 20 AAT1123 1MHz Step-Down Converter 1123.2006.05.1.5 ...