Datasheet ADP3050 (Analog Devices)

200 kHz, 1 A High Voltage Step-Down Switching Regulator Data Sheet ADP3050 FEATURES FUNCTIONAL BLOCK DIAGRAM Wide input voltage range: 3.6 V to 30 V BIAS IN 3 8 Adjustable and fixed (3.3 V, 5 V) output options Integrated 1 A power switch CURRENT SENSE 2.50V AMPLIFIER Uses small surface-mount components SD 6 REGULATOR Cycle-by-cycle current limiting GND 7 Peak input voltage (100 ms): 60 V Configurable as a buck, buck-boost, and SEPIC FREQUENCY CURRENT regulator AND CURRENT LIMIT LIMIT FOLDBACK Available in 8-lead SOIC package Supported by ADIsimPower™ design tool + 200kHz APPLICATIONS OSCILLATOR 2 BOOST FB 4 Industrial power systems CMP PC peripheral power systems S Q DRIVER Preregulator for linear regulators R 1 SWITCH Distributed power systems Automotive systems gm 1.2V ADP3050 Battery chargers
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5 COMP
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GENERAL DESCRIPTION
The ADP3050 is a current mode monolithic buck (step down) The ADP3050 includes a shutdown input that places the device PWM switching regulator that contains a high current 1 A power in a low power mode, reducing the total supply current to under switch and all control, logic, and protection functions. It uses a 20 µA. Internal protection features include thermal shutdown unique compensation scheme allowing the use of any type of circuitry and a cycle-by-cycle current limit for the power switch output capacitor (tantalum, ceramic, electrolytic, OS-CON). to provide complete device protection under fault conditions. Unlike some buck regulators, the design is not restricted to using The ADP3050 provides excellent line and load regulation, a specific type of output capacitor or ESR value. maintaining typically less than ±3% output voltage accuracy A special boosted drive stage is used to saturate the NPN power over temperature and under all input voltage and output switch, providing a system efficiency higher than conventional current conditions. bipolar buck switchers. Further efficiency improvements are The ADP3050 is specified over the industrial temperature range obtained by using the low voltage regulated output to provide of −40°C to +85°C and is available in a thermal y enhanced 8-lead the internal operating current of the device. A high switching (not Pb-free only) SOIC package and a standard 8-lead (Pb-free frequency al ows the use of small external surface-mount compo- only) RoHS-compliant SOIC package. nents. A wide variety of standard off-the-shelf devices can be used, providing a great deal of design flexibility. A complete regulator design requires only a few external components.
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Document Outline Features Applications Functional Block Diagram General Description Revision History Specifications Absolute Maximum Ratings ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Setting the Output Voltage Applications Information ADIsimPower Design Tool Inductor Selection Continuous Mode Discontinuous Mode Inductor Core Types and Materials Choosing an Inductor Output Capacitor Selection Choosing an Output Capacitor Catch Diode Selection Choosing a Catch Diode Input Capacitor Selection Discontinous Mode Ringing Setting the Output Voltage Frequency Compensation Current Limit/Frequency Foldback Bias Pin Connection Boosted Drive Stage Start-Up/Minimum Input Voltage Thermal Considerations Board Layout Guidelines Typical Applications 5 V to 3.3 V Buck (Step-Down) Regulator Inverting (Buck Boost) Regulator Dual Output SEPIC Regulator Outline Dimensions Ordering Guide