AAT1162 12V, 1.5A Step-Down DC/DC Converter General Description Features The AAT1162 is an 800kHz high efficiency stepdown DC/DC converter. With a wide input voltage range of 4.0V to 13.2V, the AAT1162 is an ideal choice for dual-cell Lithium-ion battery-powered devices and mid-power-range regulated 12V-powered industrial applications. The internal power switches are capable of delivering up to 1.5A to the load. • • • The AAT1162 is a highly integrated device, simplifying system-level design. Minimum external components are required for the converter. The AAT1162 optimizes efficiency throughout the entire load range. It operates in a combination PWM/Light Load mode for improved light-load efficiency. The high switching frequency allows the use of small external components. The low current shutdown feature disconnects the load from VIN and drops shutdown current to less than 1µA. The AAT1162 is available in a Pb-free, space-saving, thermally-enhanced 16-pin TDFN34 packageand is rated over an operating temperature range of -40°C to +85°C. • • • • • • • • • • SwitchReg™ Input Voltage Range: 4.0V to 13.2V Up to 1.5A Load Current Fixed or Adjustable Output: — Output Voltage: 0.6V to VIN Low 115µA No-Load Operating Current Less than 1µA Shutdown Current Up to 96% Efficiency Integrated Power Switches 800kHz Switching Frequency Soft Start Function Short-Circuit and Over-Temperature Protection Minimum External Components TDFN34-16 Package Temperature Range: -40°C to +85°C Applications • • • • • • • Distributed Power Systems Industrial Applications Laptop Computers Portable DVD Players Portable Media Players Set-Top Boxes TFT LCD Monitors and HDTVs Typical Application L Input: 4.0V ~ 13.2V IN CIN LX 2.2µH EN DGND AIN Output: 0.6V min, 1.5A max AAT1162 FB COUT 47µF 1162.2007.09.1.2 COMP PGND LDO AGND 1 AAT1162 12V, 1.5A Step-Down DC/DC Converter Pin Descriptions Pin # Symbol 1, 2, EP2 LX 3, 12 4, 5 N/C IN 6, 13, 14, EP1 DGND 7 AIN 8 LDO 9 FB 10 COMP 11 15 AGND EN 16 PGND Function Power switching node. LX is the drain of the internal P-channel switch and N-channel synchronous rectifier. Connect the output inductor to the two LX pins and to EP2. A large exposed copper pad under the package should be used for EP2. Not connected. Power source input. Connect IN to the input power source. Bypass IN to DGND with a 22µF or greater capacitor. Connect both IN pins together as close to the IC as possible. An additional 100nF ceramic capacitor should also be connected between the two IN pins and DGND, pin 6 Exposed Pad 1 Digital Ground, DGND. The exposed thermal pad (EP1) should be connected to board ground plane and pins 6, 13, and 14. The ground plane should include a large exposed copper pad under the package for thermal dissipation (see package outline). Internal analog bias input. AIN supplies internal power to the AAT1162. Connect AIN to the input source voltage and bypass to AGND with a 0.1µF or greater capacitor. For additional noise rejection, connect to the input power source through a 10Ω or lower value resistor. Internal LDO bypass node. The output voltage of the internal LDO is bypassed at LDO. The internal circuitry of the AAT1162 is powered from LDO. Do not draw external power from LDO. Bypass LDO to AGND with a 1µF or greater capacitor. Output voltage feedback input. FB senses the output voltage for regulation control. For fixed output versions, connect FB to the output voltage. For adjustable versions, drive FB from the output voltage through a resistive voltage divider. The FB regulation threshold is 0.6V. Control compensation node. Connect a series RC network from COMP to AGND, R = 51k and C = 270pF. Analog signal ground. Connect AGND to PGND at a single point as close to the IC as possible. Active high enable input. Drive EN high to turn on the AAT1162; drive it low to turn it off. For automatic startup, connect EN to IN through a 4.7kΩ resistor. EN must be biased high, biased low, or driven to a logic level by an external source. Do not let the EN pin float when the device is powered. Power ground. Connect AGND to PGND at a single point as close to the IC as possible. Pin Configuration TDFN34-16 (Top View) LX LX N/C IN IN DGND AIN LDO 2 1 2 EP2 16 15 3 14 4 13 5 6 EP1 12 11 7 10 8 9 PGND EN DGND DGND N/C AGND COMP FB 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Absolute Maximum Ratings1 Symbol Description VIN, VAIN VLX VFB VEN TJ Input Voltage LX to GND Voltage FB to GND Voltage EN to GND Voltage Operating Junction Temperature Range Value Units -0.3 to 14 -0.3 to VIN + 0.3 -0.3 to VIN + 0.3 -0.3 to VIN + 0.3 -40 to 150 V V V V °C Value Units 2.7 37 W °C/W Thermal Information3 Symbol PD θJA Description Maximum Power Dissipation4 Thermal Resistance 1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Based on long-term current density limitation. 3. Mounted on an FR4 board. 4. Derate 2.7mW/°C above 25°C. 1162.2007.09.1.2 3 AAT1162 12V, 1.5A Step-Down DC/DC Converter Electrical Characteristics1 4.0V < VIN < 13.2V. CIN = COUT = 22µF; L = 4.7µH, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C. Symbol VIN VUVLO IQ ISHDN VOUT VOUT ∆VOUT/ VOUT/∆VIN ∆VOUT/ IOUT VFB IFBLEAK FOSC Description Input Under-Voltage Lockout Supply Current Shutdown Current Output Voltage Range Output Voltage Accuracy 0.3 115 IOUT = 0A to 1.5A VIN = 4.5V to 13.2V Load Regulation VIN = 12V, VOUT = 5V, IOUT = 0A to 1.5A Feedback Reference Voltage (adjustable version) No Load, TA = 25°C FB Leakage Current VOUT = 1.2V RDS(ON)H P-Channel On Resistance RDS(ON)L N-Channel On Resistance Efficiency PMOS Current Limit LX Leakage Current Typ 4.0 Rising Hysteresis No Load VEN = GND Line Regulation DC TON TS ILXLEAK Min Input Voltage Range PWM Oscillator Frequency Foldback Frequency Maximum Duty Cycle Minimum Turn-On Time Soft-Start Time η ILIM Conditions 0.6 -2.5 0.023 Max Units 13.2 4.0 V 200 1 0.94 VIN 2.5 µA µA V % 0.100 %/V 0.4 0.59 0.60 0.6 2 0.8 200 Adjustable Version Fixed Version % 0.61 0.2 1 94 VIN VIN VIN VIN VIN = = = = = 12V 6V 12V 6V 12V, VOUT = 5V, IOUT = 1.5A 2.0 VIN = 13.2V, VLX = 0 to VIN V 100 200 0.12 0.15 0.06 0.08 93 3.0 V µA MHz kHz % ns µs Ω Ω 1 % A µA 1. The AAT1162 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 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Electrical Characteristics1 4.0V < VIN < 13.2V. CIN = COUT = 22µF; L = 4.7µH, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C. Symbol TSD THYS VIL VIH IEN Description Over-Temperature Shutdown Threshold Over-Temperature Shutdown Hysteresis EN Logic Low Input Threshold EN Logic High Input Threshold EN Input Current Conditions Min Typ Max 140 °C 25 °C 0.4 VEN = 0V, VEN = 13.2V 1.4 -1.0 Units 1.0 V V µA 1. The AAT1162 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. 1162.2007.09.1.2 5 AAT1162 12V, 1.5A Step-Down DC/DC Converter Typical Characteristics Test circuit of Figure 2, unless otherwise specified. Efficiency vs. Output Current Efficiency vs. Output Current (VOUT = 5V) (VOUT = 3.3V) 100 100 90 90 VIN = 10V 60 VIN = 8.4V 50 40 VIN = 6V 30 VIN = 12V 80 VIN = 12V 70 Efficiency (%) Efficiency (%) 80 70 VIN = 8.4V 60 50 VIN = 6V 40 VIN = 5V 30 20 20 10 10 0 0 0.001 0.01 0.1 1 0.001 10 0.01 0.1 Output Current (A) VIN = 12V 140 810 5V 805 Current (µA) Switching Frequency (kHz) 150 815 800 795 12V 785 780 130 120 110 VIN = 5V 100 90 775 80 770 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 -40 -30 -20 -10 90 Temperature (°C) 0 10 20 30 40 50 60 70 80 90 Temperature (°C) Non-Switching Quiescent Current vs. Input Voltage Switching Quiescent Current vs. Input Voltage (VOUT = 5V) 150 25°C 85°C 130 Quiescent Current (µA) 220 140 Current (µA) 10 Non-Switching Quiescent Current vs. Temperature 820 790 1 Output Current (A) Switching Frequency vs. Temperature 120 110 100 -40°C 90 80 5 6 7 8 9 Input Voltage (V) 6 VIN = 10V 10 11 12 210 85°C 25°C 200 190 180 -40°C 170 160 150 6 7 8 9 10 11 12 Input Voltage (V) 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Typical Characteristics Test circuit of Figure 2, unless otherwise specified. Switching Quiescent Current vs. Input Voltage On Time vs. Temperature (VOUT = 3.3V) (VOUT = 3.3V) 1000 900 200 800 85°C On Time (ns) Quiescent Current (µA) 210 25°C 190 180 170 -40°C VIN = 5V 700 600 500 VIN = 12V 400 300 200 160 100 0 -40 -30 -20 -10 150 5 6 7 8 9 10 11 12 20 30 40 50 Output Voltage Tolerance vs. Temperature Line Regulation (VOUT = 3.3V; ILOAD = 1.5A) (VOUT = 5V) 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 IOUT = 500mA 0.2 0 IOUT = 1mA -0.1 IOUT = 100mA -0.2 6 7 0 I OUT = 1mA -0.2 -0.3 6 7 8 9 Input Voltage (V) 1162.2007.09.1.2 10 11 12 Output Voltage Difference (%) IOUT = 1.5A 0.1 5 8 9 10 11 12 (VOUT = 5V) I OUT = 1A I OUT = 10mA I OUT =100mA IOUT = 10mA -0.3 Load Regulation -0.1 90 0.1 Line Regulation 0.2 80 IOUT = 1.5A Input Voltage (V) 0.3 70 0.3 Temperature (°C) 0.4 60 0.4 (VOUT = 3.3V) Output Voltage Difference (%) 10 Temperature (°C) Output Voltage Difference (%) Output Voltage Difference (%) Input Voltage (V) 0 0.4 VIN = 12V 0.3 VIN = 10V 0.2 0.1 0 VIN = 8.4V -0.1 VIN = 6V -0.2 -0.3 0.0001 0.001 0.01 0.1 1 10 Output Current (mA) 7 AAT1162 12V, 1.5A Step-Down DC/DC Converter Typical Characteristics Test circuit of Figure 2, unless otherwise specified. Load Regulation N-Channel RDS(ON) vs. Temperature 120 0.4 VIN = 12V 0.3 VIN = 10V 0.2 Resistance (mΩ Ω) Output Voltage Difference (%) (VOUT = 3.3V) 0.1 VIN = 8.4V 0 VIN = 5V VIN = 6V -0.1 -0.2 80 60 40 VIN = 12V 20 0 -0.3 0.0001 VIN = 6V 100 0.001 0.01 0.1 1 -40 10 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 Temperature (°C) Output Current (mA) P-Channel RDS(ON) vs. Temperature Line Transient 8 3.48 180 7 3.45 6 3.42 5 3.39 4 3.36 3 3.33 2 3.3 1 3.27 0 3.24 160 Input Voltage (top) (V) 200 VIN = 6V 140 120 100 80 60 VIN = 12V 40 20 0 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 Temperature (°C) Load Transient (VOUT = 3.3V; CFF = 100pF) Output Voltage (top) (V) 4.4 1A 3 10mA 4.2 2 1.5 4 1 3.8 0.5 3.6 0 Time (50µs/div) 8 2.5 3.6 3.5 3.4 3 3.2 2.5 1.2A 3 2 10mA 2.8 1.5 2.6 1 2.4 0.5 2.2 0 2 -0.5 Load and Inductor Current (bottom) (A) 4.6 3.5 Load and Inductor Current (bottom) (A) 4 Output Voltage (top) (V) Load Transient 5 4.8 Time (20µs/div) (VOUT = 5V; CFF = 100pF) 5.2 Output Voltage (bottom) (V) Resistance (mΩ Ω) (VOUT = 3.3V; CFF = 100pF) Time (50µs/div) 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Typical Characteristics Load Transient (VOUT = 5V; No CFF) (VOUT = 3.3V; No CFF) 4 5.1 3.5 4.8 3 1A 4.5 2.5 10mA 4.2 3.9 1.5 3.6 1 3.3 0.5 3 0 Time (50µs/div) 1162.2007.09.1.2 2 3.6 4 3.4 3.5 3.2 3 3 1.2A 2.5 2 2.8 10mA 2.6 1.5 2.4 1 2.2 0.5 0 2 Load and Inductor Current (bottom) (A) 5.4 Output Voltage (top) (V) Load Transient Load and Inductor Current (bottom) (A) Output Voltage (top) (V) Test circuit of Figure 2, unless otherwise specified. Time (50µs/div) 9 AAT1162 12V, 1.5A Step-Down DC/DC Converter Functional Block Diagram AIN IN LDO Note 1 FB Internal Power Current Sense Amp + LDO + + Error Amp Current Mode Comparator - Control Logic Reference LX PGND AGND EN DGND COMP . to the Note 1: For fixed output voltage versions, FB is connected error amplifier through the resistive voltage divider shown. Functional Description The AAT1162 is a current-mode step-down DC/DC converter that operates over a wide 4V to 13.2V input voltage range and is capable of supplying up to 1.5A to the load with the output voltage regulated as low as 0.6V. Both the P-channel power switch and N-channel synchronous rectifier are internal, reducing the number of external components required. The output voltage is adjusted by an external resistor divider; fixed output voltage versions are available upon request. The regulation system is externally compensated, allowing the circuit to be optimized for each application. The AAT1162 includes cycle-by-cycle current limiting, frequency foldback for improved short-circuit performance, and thermal overload protection to prevent damage in the event of an external fault condition. 10 Control Loop The AAT1162 regulates the output voltage using constant frequency current mode control. The AAT1162 monitors current through the high-side Pchannel MOSFET and uses that signal to regulate the output voltage. This provides improved transient response and eases compensation. Internal slope compensation is included to ensure the current "inside loop" stability. High efficiency is maintained under light load conditions by automatically switching to variable frequency Light Load control. In this condition, transition losses are reduced by operating at a lower frequency at light loads. 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Short-Circuit Protection The AAT1162 uses a cycle-by-cycle current limit to protect itself and the load from an external fault condition. When the inductor current reaches the internally set 3.0A current limit, the P-channel MOSFET switch turns off and the N-channel synchronous rectifier is turned on, limiting the inductor and the load current. During an overload condition, when the output voltage drops below 50% of the regulation voltage (0.3V at FB), the AAT1162 switching frequency drops by a factor of 4. This gives the inductor current ample time to reset during the off time to prevent the inductor current from rising uncontrolled in a short-circuit condition. Thermal Protection The AAT1162 includes thermal protection that disables the regulator when the die temperature reaches 140ºC. It automatically restarts when the temperature decreases by 25ºC or more. Applications Information Setting the Output Voltage Figure 1 shows the basic application circuit for the AAT1162 and output setting resistors. Resistors R1 and R2 program the output to regulate at a voltage higher than 0.6V. To limit the bias current required for the external feedback resistor string while maintaining good noise immunity, the minimum suggested value for R2 is 5.9kΩ. Although a larger value will further reduce quiescent current, it will also increase the impedance of the feedback node, making it more sensitive to external noise and interference. Table 1 summarizes the resistor values for various output voltages with R2 set to either 5.9kΩ for good noise immunity or 59kΩ for reduced no load input current. EP2 VIN 4.5V -13.2V C1 22µF R4 10Ω C6 0.1µF C7 1µ F 3 EN 4 IN 5 IN 7 AIN 6 DGND 13 DGND 16 PGND LX LX LX AAT1162 FB 1 2 9 COMP 10 AGND 11 DGND DGND EP1 LDO 14 L1 3.8µH C3 100pF R3 50kΩ VOUT 5V, 2A R1 43.2kΩ C2 22µF R2 5.9kΩ 8 C5 1µ F C4 270pF Figure 1: Typical Application Circuit. The adjustable feedback resistors, combined with an external feed forward capacitor (C3 in Figure 1), deliver enhanced transient response for extreme pulsed load applications. The addition of the feed forward capacitor typically requires a larger output capacitor C2 for stability. Larger C3 values reduce overshoot and undershoot during startup and load changes. However, do not exceed 470pF to maintain stable operation. 1162.2007.09.1.2 11 AAT1162 12V, 1.5A Step-Down DC/DC Converter The external resistors set the output voltage according to the following equation: ⎛ R1 ⎞ VOUT = 0.6V 1 + ⎝ R2 ⎠ or ⎛ VOUT ⎞ R1 = V -1 · R2 ⎝ REF ⎠ Table 1 shows the resistor selection for different output voltage settings. VOUT (V) R2 = 5.9(kΩ) R1 (kΩ) R2 = 59(kΩ) R1 (kΩ) 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 5.0 1.96 2.94 3.92 4.99 5.90 6.81 7.87 8.87 11.8 12.4 13.7 18.7 26.7 43.2 19.6 29.4 39.2 49.9 59.0 68.1 78.7 88.7 118 124 137 187 267 432 Table 1: Resistor Selection for Different Output Voltage Settings. Standard 1% Resistors are Substituted for Calculated Values. 12 Inductor Selection For most designs, the AAT1162 operates with inductors of 2µH to 4.7µH. For output voltages above 3.3V, the minimum recommended inductor is 3.8µH. For 3.3V and below, use a 2 to 2.2µH inductor. For optimum voltage-positioning load transients, choose an inductor with DC series resistance in the 15mΩ to 20mΩ range. For higher efficiency at heavy loads (above 1A), or minimal load regulation (but some transient overshoot), the resistance should be kept below 18mΩ. The DC current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation (1.5A + 263mA). Table 2 lists some typical surface mount inductors that meet target applications for the AAT1162. Manufacturer's specifications list both the inductor DC current rating, which is a thermal limitation, and the peak current rating, which is determined by the saturation characteristics. The inductor should not show any appreciable saturation under normal load conditions. Some inductors may meet the peak and average current ratings yet result in excessive losses due to a high DCR. Always consider the losses associated with the DCR and its effect on the total converter efficiency when selecting an inductor. For example, the 3.7µH CDR7D43 series inductor selected from Sumida has an 18.9mΩ DCR and a 4.3ADC current rating. At full load, the inductor DC loss is 28mW which gives only a 0.4% loss in efficiency for a 1.5A, 5V output. Compensation The AAT1162 step-down converter uses peak current mode control with slope compensation scheme to maintain stability with lower value inductors for duty cycles greater than 50%. The regulation feedback loop in the IC is stabilized by the components connected to the COMP pin, as shown in Figure 1. 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Manufacturer Part Number Sumida Sumida Coilcraft CDRH103RNP-2R2N CDR7D43MNNP-3R7NC MSS1038-382NL L (µH) Max DCR (mΩ) Rated DC Current (A) Size WxLxH (mm) 2.2 3.7 3.8 16.9 18.9 13 5.10 4.3 4.25 10.3x10.5x3.1 7.6x7.6x4.5 10.2x7.7x3.8 Table 2: Typical Surface Mount Inductors. Layout Guidance Figure 2 is the schematic for the evaluation board. When laying out the PC board, the following layout guideline should be followed to ensure proper operation of the AAT1162: 1. Exposed pad EP1 must be reliably soldered to PGND/DGND/AGND. The exposed thermal pad should be connected to board ground plane and pins 6, 11, 13, 14 and 16. The ground plane should include a large exposed copper pad under the package for thermal dissipation. 2. The power traces, including GND traces, the LX traces and the VIN trace should be kept short, direct and wide to allow large current flow. The L1 connection to the LX pins should be as short as possible. Use several via pads when routing between layers. 3. Exposed pad pin EP2 must be reliably soldered to the LX pins 1 and 2. The exposed thermal pad should be connected to the board LX connection and the inductor L1 and also pins 1 and 2. The LX plane should include a large exposed copper pad under the package for thermal dissipation. 1162.2007.09.1.2 4. The input capacitors (C9 and C1) should be connected as close as possible to IN (Pins 4 and 5) and DGND (Pin 6) to get good power filtering. 5. Keep the switching node LX away from the sensitive FB node. 6. The feedback trace for the FB pin should be separate from any power trace and connected as closely as possible to the load point. Sensing along a high-current load trace will degrade DC load regulation. The feedback resistors should be placed as close as possible to the FB pin (Pin 9) to minimize the length of the high impedance feedback trace. 7. The output capacitors C3, 4, and 5 and L1 should be connected as close as possible and there should not be any signal lines under the inductor. 8. The resistance of the trace from the load return to the PGND (Pin 16) should be kept to a minimum. This will help to minimize any error in DC regulation due to differences in the potential of the internal signal ground and the power ground. 13 AAT1162 12V, 1.5A Step-Down DC/DC Converter Enable J1 1 EP2 U1 VIN R5 4.7k FB1 1.5A 330 4 R4 10 C2 10µF 16V C1 22µF 16V 15 5 3 C9 0.1µF 16V 7 C8 0.1µF 16V EN IN IN N/C AIN AAT1162 LX 6 13 DGND DGND 16 PGND DGND LX LX FB COMP AGND N/C DGND LDO VOUT L1 1 2 3.8µH 6A C10 100pF 9 10 11 12 R3 51k C11 NP 14 8 LDO R1 43.2k R2 5.9k C3 22µF C3 22µF C3 22µF C7 270pF EP1 C6 1µF DGND Note: Connect GND, DGND, and AGND at IC FB1: Chip Ferrite Bead C10: Increase C10 to reduce overshoot Figure 2: AAT1162 Evaluation Board Schematic. Figure 3: AAT1162 Evaluation Board Component Side Layout. 14 Figure 4: AAT1162 Evaluation Board Solder Side Layout. 1162.2007.09.1.2 AAT1162 12V, 1.5A Step-Down DC/DC Converter Ordering Information Package Marking1 Part Number (Tape and Reel)2 TDFN34-16 YYXYY AAT1162IRN-0.6-T1 All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at http://www.analogictech.com/pbfree. Package Information TDFN34-16 1.600 ± 0.050 0.35 REF 0.450 ± 0.050 0.230 ± 0.050 4.000 ± 0.050 Index Area 2.350 ± 0.050 0.700 ± 0.050 3.000 ± 0.050 0.25 REF 0.430 ± 0.050 1.600 ± 0.050 Top View 0.750 ± 0.050 Bottom View 0.230 ± 0.050 0.050 ± 0.050 Side View All dimensions in millimeters. 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. 1162.2007.09.1.2 15 AAT1162 12V, 1.5A Step-Down DC/DC Converter © Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Except as provided in AnalogicTech’s terms and conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer’s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific 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. Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 16 1162.2007.09.1.2