The **ADP172ACBZ-2.9-R7** is a low dropout (LDO) linear regulator designed for high-performance analog and mixed-signal applications where space and power efficiency are critical. --- ### 1. Key Technical Specifications Below are the primary electrical characteristics of the device: | Feature | Specification | | :--- | :--- | | **Output Voltage** | 2.9V (Fixed) | | **Input Voltage Range** | 1.6V to 3.6V | | **Maximum Output Current** | 300 mA | | **Dropout Voltage** | 50 mV @ 300 mA load | | **Quiescent Current (No Load)** | 23 µA | | **Shutdown Current** | < 1 µA | | **Package Type** | 4-ball WLCSP (Wafer Level Chip Scale Package) | | **PSRR** | 70 dB @ 1 kHz | --- ### 2. Functional Description The ADP172 series is optimized for battery-operated devices. Its main internal components include: * **Internal Reference:** Provides a stable voltage base for the regulation loop. * **Error Amplifier:** Compares the feedback voltage with the internal reference to maintain 2.9V output. * **Pass Transistor:** A P-channel MOSFET that regulates the flow of current from input to output. * **Protection Circuitry:** * *Thermal Overload Protection:* Prevents damage from overheating. * *Short-Circuit Protection:* Limits current if the output is grounded. --- ### 3. Application Circuit Example To operate this LDO, minimal external components are required. It is designed to be stable with small 1 µF ceramic capacitors. ```c // Typical Connection Diagram [Vin] ----[ 1uF Cap ]---- (IN) (OUT) ----[ 1uF Cap ]---- [Vout: 2.9V] | | ( ADP172 ) | | [Enable] ---------------- (EN) (GND) ------------------- [Ground] ``` --- ### 4. Part Number Breakdown: `ADP172ACBZ-2.9-R7` Understanding the nomenclature helps in identifying variants: * **ADP172:** Model series (300mA, Low Quiescent Current LDO). * **A:** Operating temperature range (-40°C to +125°C). * **CBZ:** WLCSP package (Halogen-free/RoHS compliant). * **2.9:** Output voltage (Fixed 2.9 Volts). * **R7:** 7-inch reel packaging (typically 3,000 units). --- ### 5. Typical Use Cases * **Mobile Phones:** Powering camera modules or sensors. * **Wearables:** Ideal for smartwatches due to the tiny WLCSP footprint. * **Portable Medical Equipment:** Low noise output ensures sensor accuracy. * **Digital Cameras:** Stable 2.9V rail for image processors.