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Numéro de sérieAAT2789
CategoriePower Management => DC-DC Converters => Step-down
DescriptionLow Noise, High Frequency Dual Step-Down Converter
The AAT2789 is a 2-channel synchronous step-down converter operating from an input voltage range of 2.7V to 5.5V, making it the ideal choice for single-cell Lithiumion/ polymer battery powered systems or low voltage 3.3V and 5V based consumer equipment.

Channel 1 delivers up to 1700mA output current while Channel 2 delivers up to 800mA. Both converters incorporate a unique low noise architecture which reduces output ripple and spectral noise.

The AAT2789 uses a high switching frequency to minimize external filter sizing. Peak current mode control eliminates external compensation while optimizing transient performance and stability.
SociétéAnalogic Corporation
DatasheetTélécharger AAT2789 datasheet
 
 
  • Description courte

  • The a 2-channel synchronous step-down converter operating from an input voltage range to 5.5V, making it the ideal choice for single-cell Lithiumion/polymer battery powered systems or low voltage 3.3V and 5V based consumer equipment. Channel 1 delivers to 1700mA output current while Channel 2 delivers to 800mA. Both converters incorporate a unique low noise architecture which reduces output ripple and spectral noise. The AAT2789 uses a high switching frequency to minimize external filter sizing. Peak current mode control eliminates external compensation while optimizing transient performance and stability. The AAT2789 requires a minimum of external components to realize a high efficiency dual-output step-down converter while minimizing solution size and footprint. Each of the step-down regulators has an independent input and enable pin. Externally adjustable output voltage is provided. Light load operating mode provides high efficiency over the entire load range. Low quiescent current enables excellent life for battery powered systems. The AAT2789 is available a 3x4mm Pb-free 16-pin TDFN package and is rated over the to 85°C operating temperature range.

    Low Noise, High Frequency Dual Step-Down Converter
    Features

    · VIN Range: to 5.5V Output Voltage Range: 0.6V to VIN Low Noise Light Load Mode Low Ripple PWM Mode Output Current: Channel 1: 1700mA Channel 2: 800mA Highly Efficient Step-Down Converters Low RDS(ON) Integrated Power Switches 100% Duty Cycle High Switching Frequency Peak Current Mode Control Internal Compensation Excellent Transient Response Internal Soft Start Fast Turn-On Time Over-Temperature Protection Current Limit Protection Low Profile TDFN34-16 Package to 85°C Temperature Range

    Applications

    · Cellular and Smart Phones Digital Cameras Handheld Instruments Mass Storage Systems Microprocessor / DSP Core / IO Power PDAs and Handheld Computers Portable Media Players USB Devices Wireless Data Systems

    No connect. Power ground pin for Channel 2 step-down converter. Connect return of Channel 2 input and output capacitors close to this pin for best noise performance. Channel 2 step-down converter switching pin. Connect output inductor to this pin. Inductor value is determined by output voltage. Input supply voltage pin for Channel 2 step-down converter. Connect a 10F ceramic input capacitor close to this pin or connect to VP1. Operating input voltage range to 5.5V. Input supply pin for Channel 1. Must be closely decoupled. Enable Channel 1 input pin. Active high. Input supply voltage pin for Channel 1 step-down converter. Connect a 10F ceramic input capacitor close to this pin. Operating input voltage range to 5.5V. Channel 1 step-down converter switching pin. Connect output inductor to this pin. Inductor value is determined by output voltage. Power ground pin for Channel 1 step-down converter. Connect return of Channel 1 input and output capacitors close to this pin for best noise performance. Feedback pin for Channel 1. Connect an external resistor divider to this pin to program the output voltage to the desired value. Signal ground for Channel 1. Input supply pin for Channel 2. Must be closely decoupled. Enable Channel 2 input pin. Active high. Feedback pin for Channel 2. Connect an external resistor divider to this pin to program the output voltage to the desired value. Signal Ground for Channel 2. Exposed paddle. Connect to PGND1 and PGND2 as close as possible to the device. Use properly sized vias for thermal coupling to the ground plane. See PCB layout guidelines.

    SystemPowerTM Low Noise, High Frequency Dual Step-Down Converter
    Description

    VCC1, VCC2 voltages to PGND, AGND VLX2 to PGND, AGND VFB2 to PGND, AGND VEN2 to PGND, AGND Operating Junction Temperature Range Maximum Soldering Temperature (at leads, 10 sec)

    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. Mounted a FR4 board. 3. Derate 20mW/°C above 25°C ambient temperature.