PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package General Description Features The AAT2265 is designed for single-cell or dual-cell alkaline, NiMH or NiCd battery-powered applications. It is a high efficiency, synchronous, high frequency, step-up converter with true output disconnect during shutdown (<1.0A), start-up inrush current limit, and limited shortcircuit protection. * * * * * * * The high 2MHz switching frequency and completely integrated control circuitry minimize the total solution footprint area while maintaining excellent regulation, ripple, and transient response throughout the full load range. Light load switching frequency modulation and low quiescent current maintain high efficiency performance for light load and sleep mode conditions. With a 1A peak switch current limit, the AAT2265 is capable of delivering 100mA to the load with a single AA cell battery or up to 250mA from dual AA cell batteries. The device has a 1.0V start-up voltage with operation down to 0.8V, making it ideal for battery operated consumer products that require higher voltages by replacing two AA batteries with a single AA cell. The AAT2265 is available in a Pb-free, space-saving 2.0x2.1mm 8-pin SC70JW package and is rated over the -40C to +85C temperature range. * * * * * * * * * * 100mA Output from a Single AA Cell Input 250mA Output from a Dual AA Cell Input VIN Operation Range: 0.8V to VOUT Up to 93% Efficiency Low Start-Up Voltage: 1.0V Typical Internal Synchronous Rectifier Current Mode Control with Internal Feedback and Compensation 2MHz Switching Frequency 1A Current Limit Maintains High Efficiency Over the Output Current Range for Improved Battery Life Low 65A No Load Bias Current True Load Disconnect Limited Short-Circuit and Over-Current Protection Inrush Current Limit and Current Limited Soft Start Low Shutdown Current: <1.0A -40C to +85C Temperature Range 2.0x2.1mm SC70JW-8 Package Applications * * * * * * Bluetooth(R) Headsets Digital Cameras Medical Instruments Mobile Handsets MP3 and Portable Music Players Single AA Cell Consumer Products Typical Application VIN VOUT Dual-Cell to 3.3V Efficiency vs. Output Current (VOUT = 3.3V; L = 2.2H) AAT2265 LX VCC VIN OUT 100 90 4.7F 4.7F Efficiency (%) 2.2H 80 70 VIN = 2.0V VIN = 2.4V VIN = 2.7V VIN = 3.0V 60 EN GND 50 0.1 1 10 100 1000 Output Current (mA) 2265.2009.05.1.1 www.analogictech.com 1 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Pin Descriptions Pin # Symbol 1 VCC 2 EN 3 VIN 4 LX 5 OUT 6, 7, 8 GND Function Bias supply voltage after start-up and feedback to the output voltage error amplifier. Enable pin. Logic high enables the IC. Logic low disables the IC and disconnects the load from the input. Shutdown current is <1A. Battery input voltage. Supplies the IC at start-up. Inductor connection. Ties to the drains of the P-channel synchronous rectifier and the N-channel MOSFET switch. Boost converter output voltage; connects to the P-channel synchronous MOSFET source. Bypass with ceramic capacitor to GND. Signal and power ground. Connect output capacitor return. Pin Configuration SC70JW-8 (Top View) 2 VCC 1 8 GND EN 2 7 GND VIN 3 6 GND LX 4 5 OUT www.analogictech.com 2265.2009.05.1.1 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Absolute Maximum Ratings Symbol VN TJ TOP TLEAD Description VIN, OUT, VCC, EN, LX to GND Junction Temperature Range Operating Temperature Range Maximum Soldering Temperature (at leads, 10 sec) Value Units -0.3 to 6.0 -40 to 150 -40 to 85 300 V C C C Value Units 160 625 C/W mW Thermal Characteristics1 Symbol JA PD Description Maximum Thermal Resistance Maximum Power Dissipation 1. Mounted on an FR4 board. 2265.2009.05.1.1 www.analogictech.com 3 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Electrical Characteristics1 VIN = 1.2V, TA = -40C to +85C, unless otherwise noted. Typical values are TA = 25C. Symbol Description Conditions VIN Minimum Start-Up Voltage Operating Input Voltage Range VOUT Output Voltage Accuracy ILOAD = 1mA; VOUT = 3.3V IOUT 50mA VIN = 1.0V to 2.5V, PWM Mode; VOUT = 3.3V IQ ISHDN RDS(ON)H RDS(ON)L ILIMIT IPFM VOUT/ VOUT VOUT/ VOUT/VIN FOSC DTYMAX VTH(L-IN) VTH(H-IN) Min Typ Max 1.0 Units V 0.8 VOUT VOUT - 0.1 VOUT + 0.1 V 115 A 1.0 IOUT = 50mA, L = 2.2H, VIN = 1.8V 750 400 1.0 20 89 A m m A mA % Load Regulation ILOAD = 0 to 100mA 1.5 % Line Regulation VIN = 0.8V to 2.5V; IOUT = 50mA 0.2 %/V Switching Frequency Maximum Duty Cycle Logic Input Low Threshold for EN Logic Input High Threshold for EN TA = 25C Quiescent Supply Current (Light Load Operation)2 Shutdown Current PMOS On-Resistance NMOS On-Resistance NMOS Current Limit PFM Light Load Current Threshold Efficiency No Load 65 EN = 0V, VIN = 3.3V TA = 25C TA = 25C 0.6 1.8 2.0 90 2.2 0.4 1.0 MHz % V V 1. The AAT2265 is guaranteed to meet performance specifications over the -40C to +85C operating temperature range and is assured by design, characterization, and correlation with statistical process controls. 2. IQ = IQ_VOUT + IQ_VCC. 4 www.analogictech.com 2265.2009.05.1.1 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Typical Characteristics Single-Cell to 3.3V Efficiency vs. Output Current Single-Cell to 3.3V Load Regulation (VOUT = 3.3V; L = 2.2H) (VOUT = 3.3V; L = 2.2H) 3 100 2 80 70 VIN = 1.2V VIN = 1.5V VIN = 1.8V 60 50 0.1 VOUT Error (%) Efficiency (%) 90 1 0 -1 VIN = 1.2V VIN = 1.5V VIN = 1.8V -2 -3 1 10 100 1000 0.1 1 Output Current (mA) Dual-Cell to 3.3V Efficiency vs. Output Current 1000 (VOUT = 3.3V; L = 2.2H) 3 100 VIN = 2.0V VIN = 2.4V VIN = 2.7V VIN = 3.0V 2 VOUT Error (%) 90 Efficiency (%) 100 Dual-Cell to 3.3V Load Regulation (VOUT = 3.3V; L = 2.2H) 80 70 VIN = 2.0V VIN = 2.4V VIN = 2.7V VIN = 3.0V 60 50 0.1 10 Output Current (mA) 1 0 -1 -2 -3 1 10 100 1000 0.1 Output Current (mA) 1 10 100 1000 Output Current (mA) Line Transient Response Load Transient Response (VIN = 1.9V to 2.4V; VOUT = 3.3V; IOUT = 50mA; COUT = 4.7F) (VIN = 1.2V; VOUT = 3.3V; IOUT = 50mA to 100mA; COUT = 4.7F) 1.4 3.35 3.30 3.25 3.20 Output Voltage (top) (V) Input Voltage (top) (V) 1.9 3.5 3.4 3.3 3.2 Time (100s/div) 2265.2009.05.1.1 0.15 0.10 0.05 0.00 Output Current (bottom) (A) 2.4 Output Voltage (bottom) (V) 2.9 Time (200s/div) www.analogictech.com 5 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Typical Characteristics No Load Input Current vs. Input Voltage Maximum Load Current Capability for a 4% Drop in Output Voltage vs. Input Voltage (VEN = VIN; VOUT = 3.3V) (VOUT = 3.3V) 300 600 Load Current (mA) Input Current (A) 270 240 210 180 150 120 90 60 30 0 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 500 400 300 200 100 0 1.0 3.0 1.2 1.4 1.6 Input Voltage (V) 1.8 2.0 2.2 2.4 2.6 2.8 3.0 Input Voltage (V) Switching Frequency vs. Temperature VIH and VIL vs. Input Voltage (VIN = 2V; IOUT = 100mA) 0.80 10 VIH VIL 0.75 VIH and VIL (V) Frequency Variation (%) 15 5 0 -5 0.70 0.65 0.60 -10 -15 -50 -35 -20 -5 10 25 40 55 70 0.55 0.8 85 1.2 1.6 Temperature (C) Minimum Start-Up Input Voltage vs. Load Current 2.8 3.2 3.6 (VIN = 1.5V; VOUT = 3.3V) 1.5 Output Voltage Error (%) 2.2 Input Voltage (V) 2.4 Output Voltage Error vs. Temperature 2.4 2.0 Constant Current Load 1.8 1.6 1.4 Resistive Load 1.2 1.0 0.8 0 20 40 60 80 100 120 140 160 IOUT = 1mA IOUT = 10mA IOUT = 50mA IOUT = 100mA 1.0 0.5 0.0 -0.5 -1.0 -1.5 -40 -20 0 20 40 60 80 100 Temperature (C) Load Current (mA) 6 2.0 Input Voltage (V) www.analogictech.com 2265.2009.05.1.1 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Typical Characteristics Full Load Output Ripple Light Load Output Ripple (VIN = 1.2V; VOUT = 3.3V; IOUT = 100mA) (VIN = 1.2V; VOUT = 3.3V; IOUT = 10mA) 3.3V 0V 0.6 0.4 0.2 3.30 VOUT (top) (V) VLX (middle) (V) VOUT (top) (V) VLX (middle) (V) 3.28 3.32 3.28 3.3V 0V 0.4 0.2 0.0 Time (5s/div) Soft-Start Inrush Current (VIN = 1.2V; VOUT = 3.3V; IOUT = 40mA) 3 2 1 0 0.4 0.2 0.0 Time (50s/div) 2265.2009.05.1.1 4 3 2 1 0 0.4 0.2 0.0 Input Current (bottom) (A) 4 Output Voltage (top) (V) Enable Voltage (middle) (V) Soft-Start Inrush Current (VIN = 2.4V; VOUT = 3.3V; IOUT = 100mA) Input Current (bottom) (A) Output Voltage (top) (V) Enable Voltage (middle) (V) Time (200ns/div) Inductor Current (bottom) (A) 3.30 Inductor Current (bottom) (A) 3.32 Time (500s/div) www.analogictech.com 7 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Functional Block Diagram VCC VIN Current Limit OUT Low Voltage Start-Up VREF Voltage Reference DH Mode Control 2MHz Oscillator Current Sense LX Logic Comp. DL Error Amp. EN GND Functional Description The AAT2265 synchronous step-up converter is targeted for single- or dual-cell alkaline, NiMH and NiCd battery applications. It has a 1V typical start-up voltage with operation after start-up to 0.8V. The high 2MHz switching frequency of the AAT2265 facilitates output filter component size reduction for improved power density and reduced overall footprint. It also provides greater bandwidth and improved transient response over other lower frequency step-up converters. The compensation and feedback is integrated with only three external components (CIN, COUT, L). Low RDS(ON) synchronous power switches provide high efficiency for heavy load conditions. Switching frequency modulation and low quiescent current maintains this high efficiency for light load and sleep mode conditions. 8 GND In addition to the improved efficiency, the synchronous boost has the added performance advantage of true load disconnect during shutdown (<1A shutdown current), inrush current limit, and short-circuit protection. PWM / Light Load Control The AAT2265 is a high frequency PWM peak current mode control step-up converter. For light load conditions (10 to 20mA and below), the converter transitions to a variable frequency (Light Load) mode to reduce the dominant switching losses. In addition to Light Load operation, a zero current comparator blocks reverse current in the P-channel synchronous MOSFET, forcing DCM operation at light load. These controls, along with very low quiescent current, help to maintain high efficiency over the complete load range without the compromise of increased output voltage ripple during light load conditions. www.analogictech.com 2265.2009.05.1.1 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Applications Information Start-up and Inrush Current Limit The start-up sequence of the AAT2265 varies depending upon whether the input voltage is greater than or less than 2V. Above 1V, a start-up oscillator operating at 25% duty cycle controls the synchronous power stage and charges the output to 2V. For an input voltage greater than 2V, the output is charged at a constant current of 300mA until the output reaches a voltage level just below the input voltage. The step-up converter then takes control and continues to charge the output to the steadystate voltage. The step-up converter N-channel switch current is limited to 1A and the typical start-up time is approximately 1ms dependant upon load conditions. The AAT2265 is designed to operate with a 2.2H inductor for all input/output voltage combinations. The inductor saturation current rating should be greater than the NMOS current limit specification listed in the Electrical Characteristics table. If necessary, the peak inductor current can exceed the saturation level by a small amount with no significant effect on performance. Table 1 provides a list of some suggested inductor manufacturers and their part numbers. Output and Input Capacitor Selection Shutdown and Output Disconnect A typical synchronous step-up (boost) converter has a conduction path from the input to the output via the body diode of the P-channel MOSFET. The AAT2265 design disconnects this body diode from the output and eliminates this conduction path. This enables the AAT2265 to provide true load disconnect during shutdown and inrush current limit at turn-on. Short-Circuit Protection The AAT2265 is designed to function from a single AA cell battery which is typically in the range of 1.5V to 0.8V during discharge. The part is guaranteed to operate at 0.8V with less than 50mA load current because the control circuitry is powered off the output of the boost. This unique mode of operation allows the device to run down to very low input voltages while maintaining control of regulation, temperature and short circuit protection. The P-channel synchronous MOSFET body diode disconnect feature also gives the AAT2265 the ability to provide limited output short-circuit current protection. However, when the output is shorted directly to ground, there is a loss of control circuitry, so the short circuit protection is limited by the current source of the battery. For single cell AA, the device can withstand a dead short. But since the control circuitry is not functional during the short circuit event, the part can be damaged if a source greater than an AA battery is used to power the device. A resistive short where the output does not go below approximately 2V will be short circuit protected even at higher than 1.5V input voltage levels. 2265.2009.05.1.1 Inductor Selection Surface mount X5R or X7R ceramic capacitors are suggested for both the output and the input. For the output capacitor (C1 in Figure 4) a 4.7F, 10V, X5R ceramic capacitor is necessary for stability, transient response, and ripple performance. The same 0805 sized capacitor is used for the input (C2 of Figure 4). If desired, a smaller, 0603 sized, 4.7F, 6.3V, X5R ceramic capacitor can be substituted for the input capacitor (C2). Suggested ceramic capacitor suppliers are listed in Table 1. PCB Layout Guidelines Figures 1, 2, and 3 display the evaluation board layout and suggested component placement. Due to the high switching speed of the AAT2265, it is important that the evaluation board layout be followed. Even the best switch-mode power supply design cannot overcome the problems that can be caused by a poor layout. For the AAT2265, it is necessary that C1 and C2 be placed as close as possible to the IC with a good low impedance path to the GND pins of the IC. It is also good practice to minimize the length of the trace from the OUT pin to the output inductor. This prevents switching noise from radiating into other high noise sensitive, high impedance circuits. www.analogictech.com 9 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Figure 1: AAT2265 Evaluation Board Top Side. Figure 2: Component Placement. Figure 3: AAT2265 Evaluation Board Bottom Side. 10 www.analogictech.com 2265.2009.05.1.1 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package VIN U1 AAT2265 1 1 2 3 2 3 Enable 4 L1 2.2H VCC GND EN GND VIN GND LX OUT 8 7 6 VOUT 5 C1 4.7F C2 4.7F U1 AAT2265 SC70JW-8 L1 SD3118-2R2 C1, C2 4.7F 10V 0805 X5R Figure 4: AAT2265 Evaluation Board Schematic. Manufacturer Value Part Voltage Case Size Part Number 10V 6.3V 10V 6.3V 10V 6.3V 0805 0603 0805 0603 0805 0603 GRM21BR61A475KA73L GRM188R60J475KE19D C2012X5R1A475K C1608X5ROJ475K LMK212BJ475MG JMK107BJ475MA ISAT DCR Case Size Part Number Inductor 1.50A 75m 3.2 x 3.2 x 1.55 CDRH2D14-2R2 Inductor 1.62A 69m 3.1 x 3.1 x 1.85 SD3118-2R2 Output or Input Capacitor Input Capacitor Output or Input Capacitor Input Capacitor Output or Input Capacitor Input Capacitor Murata www.murata.com 4.7F TDK www.tdk.com 4.7F Taiyo Yuden www.t-yuden.com 4.7F Manufacturer Value Part 2.2H 2.2H Sumida www.sumida.com Cooper Electronics www.cooperet.com Table 1: Suggested Component Selection. Advanced Analogic Technologies, Inc. 3230 Scott Boulevard, Santa Clara, CA 95054 Phone (408) 737-4600 Fax (408) 737-4611 (c) 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. 2265.2009.05.1.1 www.analogictech.com 11 PRODUCT DATASHEET AAT2265 SwitchRegTM Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package Ordering Information Voltage Package 3.0V 3.3V 3.6V 5.0V SC70JW-8 SC70JW-8 SC70JW-8 SC70JW-8 Marking1 Part Number (Tape and Reel)2 AAT2265IJS-3.0-T1 AAT2265IJS-3.3-T1 AAT2265IJS-3.6-T1 AAT2265IJS-5.0-T1 ZIXYY 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/about/quality.aspx. Package Information SC70JW-8 2.20 0.20 1.75 0.10 0.50 BSC 0.50 BSC 0.50 BSC 0.225 0.075 2.00 0.20 0.100 7 3 0.45 0.10 4 4 0.05 0.05 0.15 0.05 1.10 MAX 0.85 0.15 0.048REF 2.10 0.30 All dimensions in millimeters. 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. Other output voltages can be factory programmed in 100mV intervals from 2.5V to 5.0V. Contact your local sales representative for availability and minimum order quantities. Advanced Analogic Technologies, Inc. 3230 Scott Boulevard, Santa Clara, CA 95054 Phone (408) 737-4600 Fax (408) 737-4611 (c) 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. 12 www.analogictech.com 2265.2009.05.1.1