The **LD39150PU-R** is a high-accuracy, low-dropout (LDO) linear voltage regulator designed for power management in electronic circuits. It is specifically engineered to provide a stable output voltage with minimal power loss across the regulator. --- ### ## Technical Specifications Below are the primary electrical characteristics of the LD39150PU-R: | Parameter | Specification | | :--- | :--- | | **Input Voltage Range** | 1.5V to 5.5V | | **Output Current** | Up to 1.5 A | | **Dropout Voltage** | Typ. 200 mV @ 1.5 A | | **Output Voltage** | Fixed (typically 3.3V, but check suffix) | | **Operating Temp Range** | -40°C to +125°C | | **Package Type** | DFN6 (3x3 mm) | | **PSRR** | 65 dB @ 1 kHz | --- ### ## Key Internal Parts & Features 1. **Pass Transistor (P-channel MOSFET):** The core component that regulates the voltage. Because it uses a P-channel MOSFET, it can operate with a very low dropout voltage, allowing the output to be very close to the input voltage. 2. **Internal Reference Voltage:** A high-precision bandgap reference that ensures the output remains stable despite changes in temperature or input fluctuations. 3. **Protection Circuitry:** * **Current Limit:** Protects the device if the output is shorted or the load exceeds 1.5A. * **Thermal Shutdown:** Automatically turns off the regulator if the internal junction temperature exceeds safe limits (typically around 150°C). 4. **Logic Control (Enable Pin):** Features an "Enable" pin (EN) that allows the regulator to be put into a low-power shutdown mode (drawing less than 1µA) when not in use. --- ### ## Pinout Configuration (DFN6) | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **Vout** | Regulated Output Voltage | | 2 | **Vout** | Regulated Output Voltage (redundant for current) | | 3 | **ADJ/NC** | Adjustable pin or No Connection (Fixed version) | | 4 | **GND** | Ground | | 5 | **EN** | Enable Control (High = On, Low = Off) | | 6 | **Vin** | Input Supply Voltage | | Pad | **Exp Pad** | Exposed pad must be connected to GND for cooling | --- ### ## Typical Application Circuit To ensure stability, the LD39150PU-R requires external capacitors. Unlike older regulators, it is stable with low-ESR ceramic capacitors. ```markdown Vin ----[ C_in: 1uF ]----( Vin Pin ) ( Vout Pin )----[ C_out: 2.2uF ]---- Vout (Stable) (Enable Source)----------( EN Pin ) ( GND Pin )------------------------- Ground ``` ---