Infineon TLE42754D 5V Low-Dropout Voltage Regulator: Features, Applications, and Design Considerations
The Infineon TLE42754D is a monolithic integrated low-dropout voltage regulator designed to deliver a fixed 5V output with a maximum current of 450 mA. Engineered for robust performance in the harsh environments typical of automotive electronics, this IC has also found widespread use in industrial and consumer applications where reliability and efficiency are paramount.
Key Features and Specifications
The TLE42754D distinguishes itself through a combination of performance characteristics and protective features. Its very low current consumption in both operating and standby modes makes it ideal for battery-powered systems. A critical specification is its low dropout voltage, typically 200 mV at 150 mA load, which allows it to maintain regulation even when the input voltage dips close to the output level, preserving system stability.
Beyond basic regulation, the device is fortified with comprehensive protection mechanisms. It includes overtemperature shutdown, which disables the output to prevent damage from excessive junction temperature. Short-circuit protection actively limits output current if the load is faulted. Furthermore, reverse polarity protection safeguards the IC against accidental negative voltage applied to the input, a common risk in automotive environments. An integrated reset circuit with a programmable delay monitors the output voltage and provides a signal to a microcontroller during power-up, power-down, or dropout events, ensuring controlled system operation.
Primary Applications
The TLE42754D’s ruggedized design makes it a perfect fit for automotive body and convenience control modules, such as window lifters, sunroof controls, and seat control units. Its ability to handle load-dump transients and its operational temperature range align perfectly with automotive requirements.
It is also extensively used in industrial control systems and sensor power supplies where a clean, stable 5V rail is needed for microcontrollers, sensors, and logic circuits. Consumer appliances, set-top boxes, and peripheral devices further benefit from its compact design and protective features.
Essential Design Considerations
Successful implementation of the TLE42754D requires attention to several design aspects:
Input and Output Capacitors: Stability and transient response are contingent on proper external capacitors. A low-ESR capacitor is mandatory on the output, typically in the range of 10 µF to 100 µF, and a smaller input capacitor (e.g., 100 nF) is recommended for local decoupling.
Thermal Management: Despite its efficiency, power dissipation (P_DISS = (V_IN - V_OUT) I_OUT) must be calculated. For high current or high input voltage scenarios, the thermal resistance from junction to ambient (R_thJA) must be considered to ensure the chip does not exceed its maximum junction temperature of 150°C. A sufficient copper area on the PCB for the DSO-8 package is crucial for heat dissipation.
Reset Function Configuration: The delay time of the reset output is set by an external capacitor connected to the delay pin. The value of this capacitor must be chosen according to the system's required power-on reset delay.
Input Voltage Transients: While built to withstand automotive transients, applications with particularly harsh electrical noise might require additional external filtering or transient voltage suppression (TVS) diodes on the input line.
ICGOODFIND Summary
The Infineon TLE42754D is a highly reliable, feature-rich 5V low-dropout regulator. Its robust built-in protections, low dropout voltage, and integrated reset functionality make it an exceptional choice for designers seeking a simple yet effective power management solution for demanding automotive, industrial, and consumer applications.
Keywords: Low-Dropout Regulator, Automotive Grade, Reverse Polarity Protection, Thermal Shutdown, Reset Circuit
