Infineon TLE4275DV33 3V Low-Drop Voltage Regulator: Features and Application Circuits
In the realm of power management for automotive and industrial electronics, ensuring a stable and reliable voltage supply is paramount. The Infineon TLE4275DV33 is a robust 5V-to-3.3V low-dropout (LDO) voltage regulator designed specifically to meet the stringent demands of these applications. This monolithic integrated circuit provides a fixed 3.3V output with a maximum current of 450mA, making it an ideal choice for powering microcontrollers, sensors, and other low-voltage ICs.
Key Features of the TLE4275DV33
The TLE4275DV33 stands out due to its combination of performance, protection, and diagnostic features.
Very Low Dropout Voltage: With a typical dropout voltage of only 320mV at 450mA, the regulator can maintain a stable output even when the input voltage dips very close to the output level. This is crucial in automotive environments where battery voltage can sag during cranking.
High Accuracy and Low Quiescent Current: The output voltage is accurate to within ±2%, ensuring precision for sensitive loads. Its low quiescent current (typ. 40 µA) minimizes power loss when the system is in standby mode, contributing to higher overall efficiency.
Comprehensive Protection Functions: The device is equipped with overtemperature shutdown, short-circuit protection, and reverse polarity protection. This robust suite of features safeguards both the regulator itself and the connected load from potential damage due to fault conditions.
Diagnostic Capability (Reset Output): A key feature for microcontroller-based systems is the integrated reset circuit. The open-drain reset output asserts a signal if the output voltage falls below a certain threshold, providing a controlled way to initialize a microcontroller and prevent erratic operation during power-up or brownout events.
Wide Operating Range: It can handle an input voltage from 5.5V up to 42V, with transient survival capability up to 45V. This makes it exceptionally suited for the harsh 12V and 24V automotive power systems, which are notorious for load dumps and other high-voltage transients.
Typical Application Circuits
The TLE4275DV33 is designed for ease of use, requiring only a few external components for most applications.
1. Standard Application Circuit:
The basic configuration involves connecting input and output capacitors.
Input Capacitor (CIN): A ceramic capacitor (e.g., 100 nF) placed close to the IC's input pin is essential for stabilizing the input supply and improving transient response.
Output Capacitor (CQ): A low-ESR output capacitor is required for stability. The datasheet specifies a minimum value (e.g., 2.2 µF ceramic or tantalum). This capacitor determines the regulator's loop stability and its response to load changes.
Reset Delay Capacitor (CD): An optional capacitor can be added to the reset pin to ground to program a delay time for the reset signal. This ensures the microcontroller's supply voltage is fully stable before the reset is released.
2. Enhanced Protection Circuit:
For applications exposed to extreme voltage transients beyond the absolute maximum rating, an additional pre-supply filter can be added. This typically consists of a series resistor and a larger electrolytic capacitor at the input to absorb high-energy spikes before they reach the regulator.
3. Current Boost Circuit:
While the IC provides 450mA, for higher current requirements, an external PNP transistor can be connected in a bypass configuration. The TLE4275DV33 would then act as a control element, driving the base of the transistor to provide several amps of current while maintaining regulation.
The Infineon TLE4275DV33 is a highly reliable and feature-complete LDO voltage regulator engineered for the toughest environments. Its low dropout voltage, integrated reset generation, and robust protection features make it a superior and simplified solution for powering 3.3V systems in automotive, industrial, and other demanding applications, ensuring longevity and stable performance.
Keywords: Low-Dropout Regulator (LDO), Automotive Power Management, Voltage Regulation, Reset Circuit, Protection Features
