link to page 15 ADP2118Data SheetPIN CONFIGURATION AND FUNCTION DESCRIPTIONSD O ONIGNNIVPEVP61514131SYNC/MODE 112 PVINFREQ 2ADP211811 SWTRK 3TOP10 SWVIEWFB 49SW5678DDDDNNNNGGGGPPPNOTES 2 1. THE EXPOSED PAD SHOULD BE SOLDERED TO 00 AN EXTERNAL GROUND PLANE UNDERNEATH 1- THE IC FOR THERMAL DISSIPATION. 830 0 Figure 3. Pin Configuration Table 4. Pin Function Descriptions Pin No.MnemonicDescription 1 SYNC/MODE Synchronization Input (SYNC). Connect this pin to an external clock between 600 kHz and 1.4 MHz to synchronize the switching frequency to the external clock (see the Oscillator and Synchronization section for details). CCM/PFM Selection (MODE). When this pin is connected to VIN, PFM mode is disabled and the ADP2118 only works in continuous conduction mode (CCM). When this pin is connected to ground, PFM mode is enabled and becomes active at light loads. 2 FREQ Frequency Selection. Connect to GND to select 600 kHz and VIN for 1.2 MHz. 3 TRK Tracking Input. To track a master voltage, drive TRK from a voltage divider from the master voltage. If the tracking function is not used, connect TRK to VIN. 4 FB Feedback Voltage Sense Input. Connect to a resistor divider from VOUT. For the fixed output version, connect to VOUT directly. 5 GND Analog Ground. Connect to the ground plane. 6, 7, 8 PGND Power Ground. Connect to the ground plane and to the output return side of the output capacitor. 9, 10, 11 SW Switch Node Output. Connect to the output inductor. 12, 13 PVIN Power Input Pin. Connect this pin to the input power source. Connect a bypass capacitor between this pin and PGND. 14 VIN Bias Voltage Input Pin. Connect a bypass capacitor between this pin and GND and a small (10 Ω) resistor between this pin and PVIN. 15 EN Precision Enable Pin. The 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. 16 PGOOD Power-Good Output (Open Drain). Connect to a resistor to any pull-up voltage <5.5 V. 17 (EPAD) Exposed Pad The exposed pad should be soldered to an external ground plane underneath the IC for thermal dissipation. Rev. E | Page 6 of 24 Document Outline Features Applications General Description Revision History Specifications Absolute Maximum Ratings Thermal Resistance Boundary Conditions 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 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