STR3A155

PMIC - AC DC Converters, Offline Switchers

The STR3A155 is an AC/DC converter/offline switcher that can provide a step-down power supply to an operating voltage of up to 15 watts.

The STR3A155 is suited for applications that need efficient power conversion and a wide variety of switching frequencies. It is ideal for applications such as 24 V to 12.5 V, 5.0 V to 3.3 V, or 15 V to 9.0 V power supply systems.

Application fields

The STR3A155 AC to DC converter is well suited for a range of applications such as point of load (POL) systems, automotive systems, and solar/light emitting diode (LED) lighting systems. It can be used to convert highly regulated step-down outputs to matching inputs in medium or high power applications.

Working principle

The STR3A155 is an integrated pulse-width modulation (PWM) converter. It includes a power converter, a single-ended primary-inductor converter (SEPIC) and a low-side switch to achieve efficiency and flexibility in the converter design. This topology helps to simplify the design and maintenance of the power system.

The converter includes two primary side switches and a low-side switch, which are current mode controlled. The input voltage is sensed and, as a result, the peak current mode (PCM) control prevents overload conditions. This improves efficiency and system performance.

The current mode control also enables the power converter to adjust the on-time to maintain constant output voltage and current over a wide range of input voltage and load conditions. It also improves system response time and reduces output ripple in dynamic applications. The converter is also equipped with an under-voltage lockout protection (UVLO) feature and a short circuit protection (SCP) feature.

Conclusion

The STR3A155 AC/DC converter/offline switcher is a robust and reliable solution for medium and high power applications. It features a wide range of features to ensure efficiency and system performance in a variety of applications. It is well-suited for applications such as point of load systems, automotive systems, and solar/LED lighting systems.