Datasheet ADP2119, ADP2120 (Analog Devices) - 6

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ADP2119/ADP2120 Data Sheet PIN CONFIGURATION AND FUNCTION DESCRIPTIONS ADP2119/ADP2120 VIN 1 10 EN PVIN 2 9 SYNC/MODE SW 3 8 PGOOD EXPOSED PGND 4 7 TRK PAD GND 5 6 FB NOTES 1. THE EXPOSED PAD SHOULD BE SOLDERED TO
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AN EXTERNAL GROUND PLANE UNDERNEATH THE IC FOR THERMAL DISSIPATION.
08716- Figure 3. Pin Configuration (Top View)
Table 4. Pin Function Descriptions Pin No. Mnemonic Description
1 VIN Bias Voltage Input Pin. Connect a bypass capacitor (0.1 µF minimum) between this pin and GND and a small (10 Ω) resistor between this pin and PVIN. 2 PVIN Power Input Pin. Connect this pin to the input power source. Connect a bypass capacitor between this pin and PGND. 3 SW Switch Node Output. Connect this pin to the output inductor. 4 PGND Power Ground. Connect this pin to the power ground plane and to the high current return for the power MOSFET. 5 GND Analog Ground. Connect this pin to the ground plane. 6 FB Feedback Voltage Sense Input. Connect this pin to a resistor divider from V . For the fixed output version, OUT connect to V directly. OUT 7 TRK Tracking Input. To track a master voltage, drive TRK from a resistor divider from the master voltage. If the tracking function is not used, connect TRK to VIN. 8 PGOOD Power-Good Output (Open Drain). Connect this pin to a resistor to any pull-up voltage < 5.5 V. 9 SYNC/MODE Synchronization Input (SYNC). Connect this pin to an external clock between 1 MHz and 2 MHz to synchronize the switching frequency to the external clock (see the Oscillator and Synchronization section for details). FPWM/PFM Selection (MODE). When this pin is connected to VIN, the PFM mode is disabled and the part works in continuous conduction mode (CCM) only. When this pin is connected to ground, the PFM mode is enabled and becomes active at light loads. 10 EN Precision Threshold Enable Input Pin. An external resistor divider can be used to set the turn-on threshold. To enable the part automatically, connect the EN pin to VIN. This pin has a 1 MΩ pull-down resistor to GND. EPAD Exposed Pad The exposed pad should be soldered to an external ground plane underneath the IC for thermal dissipation. Rev. A | Page 6 of 24 Document Outline Features Applications Typical Application Circuit General Description Revision History Specifications Absolute Maximum Ratings Thermal Resistance Boundary Condition ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Functional Block Diagram Theory of Operation Control Scheme PWM Mode Operation PFM Mode Operation Slope Compensation Enable/Shutdown Integrated Soft Start Tracking Oscillator and Synchronization Current Limit and Short-Circuit Protection Overvoltage Protection (OVP) Undervoltage Lockout (UVLO) Thermal Shutdown Power Good (PGOOD) Applications Information ADIsimPower Design Tool Output Voltage Selection Inductor Selection Output Capacitor Selection Input Capacitor Selection Voltage Tracking Typical Application Circuits Outline Dimensions Ordering Guide