MAX17545ATP+

MAX17545ATP+ Application Field and Working Principle

The MAX17545ATP+ device is a high-efficiency, synchronous step-down DC/DC regulator that is designed to simplify the power stages of ultra-low-power applications, allowing them to achieve fast transient response, wide input voltage range, flexible output voltage capabilities, and small overall size. This device belongs to the family of PMIC (Power Management IC) and falls in the category of Voltage Regulators, and more specifically DC DC Switching Regulators.

Applications

This device is applicable for ultra-low-power applications such as smart watches, sensors, and wearables. Owing to its small form factor, it is ideal for using in space-constrained designs, as it can be operated from an input voltage range of 2.5V to 5.5V. The power-saving feature of this device helps maintain the battery life of wearable devices and consumes very low quiescent current (I_Q) of 35 μA for high efficiency. It achieves a low output voltage ripple of 10mV (typical) during steady-state operation.

Working Principle

MAX17545ATP+ operation relies on active switching of its high-side N-channel MOSFET (Metal-oxide-semiconductor field-effect transistor) switch and low-side P-channel MOSFET switch. The high-side MOSFET acts as a diode between its drain and source to allow a current flow in one direction only, while the low-side MOSFET acts as an open circuit when the gate responsibility is zero. The MAX17545ATP+ has a Pulse-Width Modulated (PWM) mode for its enhanced operating efficiency. This device switch between these two modes depending upon the application’s requirements.

When operated in PWM mode, this device switches off the internal main switches one-by-one in a given cycle. After each switch is switched off, the voltage across the inductor will begin to increase, storing energy. Once the voltage across the inductor reaches the voltage threshold, the controller will switch off both the main switches and the low-side MOSFET will transfer that stored energy to the output capacitance. When the control loop is in skip mode, this device skips switching cycles instead of switching the MOSFETs to reduce power losses and provide an improved efficiency. This device also has an adjustable soft-start feature to eliminate the inrush current.

The key features of MAX17545ATP+ device include an adjustable output voltage from 0.6V to 4.5V, fast transient response, a maximum operating frequency of 1.5MHz for 200mV load-line, and an integrated current-sense amplifier. Owing to its high level of integration, this device requires very few external components.

Conclusion

MAX17545ATP+ device is a high-efficiency, synchronous, step-down DC/DC regulator that is designed to simplify the power stages of ultra-low-power applications and provide an improved efficiency. This device can be operated from a wide input voltage range and has an adjustable output voltage range up to 4.5V. It features fast transient response and an integrated current-sense amplifier and requires very few external components. This device is immensely helpful in wearable devices and space-constrained designs.