MAX14747EWA+T

Introduction

The MAX14747EWA+T is a power management integrated circuit (PMIC) for battery chargers especially suitable for mobile devices. The charger contains several parts, so power management becomes more efficient and reliable. This article will introduce the application field and working principle of the MAX14747EWA+T.

Application Field

The MAX14747EWA+T is especially suitable for mobile devices such as smartphones, tablets, and notebooks. It is an integrated, high-efficiency, low-power component, which can significantly reduce the overall power loss of the system. Moreover, the integrated power management function decreases the component count and costs of cell phone chargers, making it cost-effective for general consumers.

The main features of the MAX14747EWA+T are AC adapters, USB port charging and battery protection. With a wide input voltage range from 3.1V to 20V, the MAX14747EWA+T is able to charge rechargeable batteries efficiently and simultaneously with the input source. For example, it supports 2A maximum charging current for quick charging and MTP VBAT temperature sensing, etc. Additionally, the MAX14747EWA+T has a low-current button pin detecting feature which helps to save power with low standby current.

Working Principle

The MAX14747EWA+T PMIC-Battery charger is controlled by a single charge controller IC. It goes through four basic steps before the battery is fully charged, namely pre-charge, constant current, constant voltage and termination.

Firstly, to start charging, the MAX14747EWA+T will check the battery voltage and apply a pre-charge stage which requires a very low current. The pre-charge current is limited by the resistor RSET. After the battery reach the pre-charge voltage threshold, the MAX14747EWA+T will enter the constant-current stage. This is the main charging stage where the current constantly increases until the battery reaches 4.2V or 4.35V depending on the type of battery.

Afterwards, the battery starts to enter the constant-voltage stage. In the constant-voltage stage, the voltage is kept at 4.2V or 4.35V, but the current gradually decreases until it reaches the 50% pre-charge current for Li-ion batteries. This point is called the termination point, once reached, charging stops to prevent overcharging. The MAX14747EWA+T provides Under Voltage lockout, current-limit protection and over-temperature protection to ensure the safety of the system.

Conclusion

To summarize, the MAX14747EWA+T PMIC-Battery charger is a high-efficiency, low-power component that is especially suitable for mobile devices such as smartphones, tablets, and notebooks. It has an integrated power management function to decrease component count, power losses and cost. Its working principle consists of 4 stages, pre-charge, constant current, constant voltage and termination. All in all, the MAX14747EWA+T PMIC-Battery charger can reduce the overall power losses and cost of a system without sacrificing performance.