## ADP151ACPZ-3.3-R7: Technical Overview The **ADP151ACPZ-3.3-R7** is a high-performance, ultra-low noise, low dropout (LDO) linear regulator manufactured by Analog Devices. It is specifically designed to power noise-sensitive analog and mixed-signal circuits. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Output Voltage** | 3.3 V (Fixed) | | **Input Voltage Range** | 2.2 V to 5.5 V | | **Maximum Output Current** | 200 mA | | **Dropout Voltage** | 140 mV @ 200 mA load | | **Quiescent Current ($I_Q$)** | 10 $\mu$A (No load) / 265 $\mu$A (Full load) | | **PSRR (Power Supply Rejection Ratio)** | 70 dB at 10 kHz | | **Output Noise** | 9 $\mu$V rms (10 Hz to 100 kHz) | | **Package Type** | 6-lead LFCSP (2mm x 2mm) | --- ### 2. Electronic Characteristics & Features #### A. Low Noise Performance One of the defining features of the ADP151 is its ultra-low output noise without the need for an external bypass capacitor. This saves PCB space while maintaining high signal integrity for sensitive RF and audio components. #### B. Low Dropout (LDO) With a dropout voltage of only 140 mV at a full 200 mA load, the regulator can maintain a stable 3.3V output even when the battery or input source drops close to the target voltage, extending battery life in portable devices. #### C. Precision Enable Pin The device includes an EN (Enable) pin. When pulled low, the device enters a shutdown mode where the current consumption drops to less than 1 $\mu$A, making it ideal for power-sequencing and energy-efficient designs. #### D. Internal Protection * **Thermal Overload Protection:** Automatically shuts down if the junction temperature exceeds safe limits. * **Short-Circuit Protection:** Prevents damage if the output is accidentally grounded. --- ### 3. Typical Application Circuit The ADP151 is designed for stable operation with small 1 $\mu$F ceramic input and output capacitors. ```mermaid graph LR Vin[Input 2.2V-5.5V] -->|Cin 1uF| IC[ADP151-3.3] EN[Enable Pin] --> IC IC -->|Cout 1uF| Vout[Output 3.3V] IC --- GND[Ground] ``` --- ### 4. Part Number Breakdown * **ADP151**: Model series (Ultra-low noise LDO). * **ACPZ**: Package code (LFCSP - Lead Frame Chip Scale Package, RoHS compliant). * **3.3**: Fixed output voltage of 3.3 Volts. * **R7**: Packaging format (7-inch Reel, typically containing 3,000 units).