Infineon TLS850D0TEV50ATMA1: Key Features and Application Notes for the 5V Low-Dropout Voltage Regulator

In the realm of power management, the 5V low-dropout (LDO) voltage regulator remains a fundamental component, providing a clean and stable supply rail for sensitive digital and analog circuits. The Infineon TLS850D0TEV50ATMA1 stands out as a robust and highly integrated solution in this category, designed to meet the demanding requirements of modern automotive and industrial applications. This article delves into its key features and provides essential application notes for design engineers.

Key Features

The TLS850D0TEV50ATMA1 is engineered for high performance and exceptional reliability. Its core function is to deliver a fixed 5V output from a higher input voltage, with a maximum output current of 500 mA. A defining characteristic of any LDO is its dropout voltage—the minimum difference between input and output voltage required for regulation. This device features an extremely low dropout voltage, typically < 200 mV at 300 mA load, which maximizes efficiency and allows operation with input voltages very close to 5V, conserving power and reducing heat dissipation.

Beyond basic regulation, the IC is packed with advanced protection and diagnostic features. These include:

Overcurrent Protection (OCB): Safely limits the output current during short-circuit conditions.

Overtemperature Protection (TSD): Shuts down the device if the junction temperature exceeds safe limits, preventing thermal damage.

Reverse Polarity Protection: Withstands negative voltage on the input pin, a critical feature for automotive environments.

Overvoltage Protection (ENABLE pin): Protects the enable pin from voltage spikes.

Reset Function: An integrated power-on reset generator with a fixed delay time provides a controlled signal to microprocessors during power-up and power-down sequences.

Error Flag (ERR): This open-drain output pin alerts the system to error conditions such as output voltage dropout (e.g., due to a short circuit) or an overtemperature event, enabling sophisticated system monitoring.

Furthermore, the device boasts a very low quiescent current in both operational and standby modes, which is paramount for battery-powered applications. Its high power supply rejection ratio (PSRR) effectively filters out noise from the input supply, ensuring a clean output voltage for noise-sensitive components like sensors and RF modules. As an AEC-Q100 qualified device, it is guaranteed to meet the stringent quality and reliability standards for automotive electronics.

Application Notes

1. Input and Output Capacitors: For stability and optimal performance, the use of external capacitors is mandatory. A low-ESR ceramic capacitor with a value of ≥ 1 µF is recommended on the input (VIN). On the output (VQ), a low-ESR ceramic capacitor of ≥ 2.2 µF is required. These capacitors should be placed as close as possible to the respective pins of the IC to minimize parasitic inductance.

2. Thermal Management: Although highly efficient, power dissipation (P_DISS = (V_IN - V_OUT) I_OUT) can become significant at high load currents and high input voltages. The exposed thermal pad (DDPAK / TO-252 package) must be soldered to a sufficient copper area on the PCB to act as a heatsink. Ensuring adequate cooling is vital for maintaining output current capability and long-term reliability.

3. Enable Pin (EN): This pin provides logic-controlled shutdown, allowing an external microcontroller to turn the regulator on or off. Pulling EN low reduces the device's quiescent current to a very low standby value. It should not be left floating; it must be tied to VIN if not used.

4. Error Monitoring: The ERR pin can be connected to a microcontroller's interrupt or GPIO pin. A pull-up resistor to a voltage level appropriate for the MCU's logic (e.g., 3.3V or 5V) is required. This allows the system to implement fail-safe procedures, log faults, or alert the user in case of a power supply issue.

5. Automotive Use: Given its AEC-Q100 qualification, this LDO is ideal for a wide range of automotive applications, including sensor power supply, body control modules, infotainment systems, and dashboard instrumentation. Its robust protection features make it resilient against the harsh electrical transients common in vehicles.

ICGOODFIND Summary

The Infineon TLS850D0TEV50ATMA1 is a highly reliable, feature-rich 5V LDO regulator that excels in demanding environments. Its combination of low dropout voltage, comprehensive protection suite, and diagnostic capabilities makes it an superior choice for designers seeking to enhance the robustness and performance of their automotive and industrial power systems.

Keywords:

1. Low-Dropout (LDO) Regulator

2. Automotive Qualified (AEC-Q100)

3. 500 mA Output Current

4. Overcurrent and Overtemperature Protection

5. Error Flag Diagnostics