Datasheet ADP2302, ADP2303 (Analog Devices)

2 A/3 A, 20 V, 700 kHz, Nonsynchronous Step-Down Regulators Data Sheet ADP2302/ ADP2303 FEATURES TYPICAL APPLICATIONS CIRCUIT Wide input voltage range: 3.0 V to 20 V VIN VIN BST Maximum load current ADP2302/ 2 A for ADP2302 ADP2303 3 A for ADP2303 VOUT PGOOD SW ±1.5% output accuracy over temperature Output voltage down to 0.8 V ON 700 kHz switching frequency OFF EN FB Current-mode control architecture GND
001
Automatic PFM/PWM mode
08833-
Precision enable pin with hysteresis
Figure 1. Typical Application Circuit
Integrated high-side MOSFET Integrated bootstrap diode Internal compensation and soft start 100 Power-good output Undervoltage lockout (UVLO) 90 Overcurrent protection (OCP) Thermal shutdown (TSD) ) 80 % 8-lead SOIC package with exposed paddle ( Y C Supported by ADIsimPower™ design t ool N 70 IE APPLICATIONS FFIC E 60 Intermediate power rail conversion DC-to-DC point of load applications V Communications and networking 50 OUT = 3.3V INDUCTOR: VLF10040T-4R7N5R4 VOUT = 5.0V Industrial and instrumentation DIODE: SSB43L Healthcare and medical 40 0 0.5 1.0 1.5 2.0 2.5 3.0 Consumer
-002
OUTPUT CURRENT (A)
08833 Figure 2. ADP2303 Efficiency vs. Output Current at VIN = 12 V
GENERAL DESCRIPTION
The ADP2302/ADP2303 are fixed frequency, current-mode The ADP2302/ADP2303 have integrated soft start circuitry to control, step-down, dc-to-dc regulators with an integrated prevent a large inrush current at power-up. The power-good power MOSFET. The ADP2302/ADP2303 can run from an signal can be used to sequence devices that have an enable input. input voltage of 3.0 V to 20 V, which makes them suitable for a The precision enable threshold voltage allows the part to be wide range of applications. The output voltage of the ADP2302/ easily sequenced from other input/output supplies. Other key ADP2303 can be down to 0.8 V for the adjustable version, while features include undervoltage lockout (UVLO), overvoltage the fixed output version is available in preset output voltage protection (OVP), thermal shutdown (TSD), and overcurrent options of 5.0 V, 3.3 V, and 2.5 V. The 700 kHz operating protection (OCP). frequency allows small inductor and ceramic capacitors to be The ADP2302/ADP2303 devices are available in the 8-lead, used, providing a compact solution. Current mode control SOIC package with exposed paddle and are rated for the −40oC provides fast and stable line and load transient performance. to +125oC junction temperature range.
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Document Outline Features Applications Typical Applications Circuit General Description Revision History Specifications Absolute Maximum Ratings Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Functional Block Diagram Theory of Operation Basic Operation PWM Mode Power Saving Mode Bootstrap Circuitry Precision Enable Integrated Soft Start Current Limit Short-Circuit Protection Undervoltage Lockout (UVLO) Thermal Shutdown (TSD) Overvoltage Protection (OVP) Power Good Control Loop Applications Information ADIsimPower Design Tool Programming Output Voltage Voltage Conversion Limitations Low Input Voltage Considerations Programming the Precision Enable Inductor Catch Diode Input Capacitor Output Capacitor Thermal Consideration Design Example Catch Diode Selection Inductor Selection Output Capacitor Selection Resistive Voltage Divider Selection Circuit Board Layout Recommendations Typical Application Circuits Outline Dimensions Ordering Guide