The **ADP7118ACPZN3.3-R7** is a high-performance, low dropout (LDO) linear regulator manufactured by Analog Devices. It is specifically designed for high-performance analog and mixed-signal circuits that require very low noise and high power supply rejection. --- ### ## Technical Specifications Overview | Parameter | Value | | :--- | :--- | | **Output Voltage** | 3.3 V (Fixed) | | **Input Voltage Range** | 2.7 V to 20 V | | **Maximum Output Current** | 200 mA | | **Dropout Voltage** | 200 mV (typical at 200 mA load) | | **PSRR (Power Supply Rejection Ratio)** | 88 dB (at 10 kHz), 68 dB (at 1 MHz) | | **Output Noise** | 11 μV rms (10 Hz to 100 kHz) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | 6-Lead LFCSP (2mm x 2mm) | --- ### ### Key Internal Components & Features The device architecture is built around several critical electronic stages to ensure stability and precision: 1. **Internal Reference:** A high-precision voltage reference that maintains the 3.3V output accuracy within ±0.8% over temperature. 2. **Error Amplifier:** Compares the feedback from the output to the internal reference. It is optimized for high speed to react quickly to load transients. 3. **Pass Element (PMOS):** Unlike NPN-based regulators, this uses a PMOS transistor, which allows for the low dropout voltage (200mV). 4. **Protection Circuitry:** * **Thermal Shutdown:** Protects the device from overheating. * **Current Limit:** Prevents damage during short-circuit conditions. * **Reverse Current Protection:** Prevents current from flowing from output to input when the input voltage drops below the output. --- ### ### Pin Configuration (6-LFCSP) | Pin No. | Name | Function | | :--- | :--- | :--- | | 1 | **VOUT** | Regulated Output Voltage (3.3V). | | 2 | **SENSE** | Connect to VOUT to sense the voltage level. | | 3 | **GND** | Ground. | | 4 | **EN** | Enable input. High = On, Low = Off. | | 5 | **NC** | No internal connection. | | 6 | **VIN** | Input Voltage Source. | | EP | **Exposed Pad** | Must be soldered to GND for thermal dissipation. | --- ### ### Application Guidelines To ensure optimal performance of the ADP7118, the following external electronic parts are typically required: * **Input Capacitor ($C_{IN}$):** A 2.2 μF ceramic capacitor is recommended to provide stability against source impedance. * **Output Capacitor ($C_{OUT}$):** A 2.2 μF ceramic capacitor (ESR < 0.2 $\Omega$) is required for stability. Higher values can improve transient response. * **Precision Systems:** Because of its high PSRR, it is commonly used to power ADCs, DACs, and precision amplifiers in RF and medical equipment.