The **ADP2118ACPZ-2.5-R7** is a high-efficiency, synchronous step-down (buck) DC-to-DC regulator manufactured by Analog Devices. This specific variant is factory-set to a fixed output voltage. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Input Voltage Range** | 2.3 V to 5.5 V | | **Output Voltage (Fixed)** | 2.5 V | | **Output Current** | Up to 3 A | | **Switching Frequency** | Selectable (600 kHz or 1.2 MHz) | | **Efficiency** | Up to 96% | | **Package Type** | 16-lead LFCSP (4mm x 4mm) | | **Operating Temperature** | -40°C to +125°C | --- ### 2. Functional Description The ADP2118 utilizes a current-mode, fixed-frequency PWM (Pulse Width Modulation) architecture. This provides excellent stability and transient response. #### Internal Components: * **Integrated MOSFETs:** It includes both high-side and low-side power switches, eliminating the need for an external Schottky diode. * **Synchronous Rectification:** This feature reduces power loss during the "off" cycle of the high-side switch, maximizing efficiency. * **Internal Compensation:** Simplifies the circuit design by reducing the number of external passive components required. --- ### 3. Pin Configuration & Features Below are the primary functional pins for the ADP2118 series: * **PVIN / VIN:** Power and control input voltage. * **SW (Switch Node):** The junction where the internal MOSFETs connect to the external inductor. * **EN (Enable):** A logic high on this pin turns the device on. * **PGOOD (Power Good):** An open-drain output that goes high when the output voltage is within 90% of the nominal value. * **FREQ:** Used to set the switching frequency to either 600 kHz (tied to GND) or 1.2 MHz (tied to VIN). * **SYNC:** Allows the device to be synchronized to an external clock. --- ### 4. Application Circuit Example A typical circuit requires minimal external components: an inductor ($L$), input capacitor ($C_{IN}$), and output capacitor ($C_{OUT}$). ```text Input (2.3V-5.5V) ----[Cin]----(PVIN) | (SW)----[Inductor]---- Output (2.5V) | | (GND) [Cout] | (GND) ``` --- ### 5. Ordering Information Deciphered The suffix **-2.5-R7** provides critical logistics and electrical data: * **2.5**: Indicates the fixed output voltage is 2.5V. * **R7**: Indicates the packaging format, specifically a 7-inch Tape and Reel (usually containing 1,500 units).