Maxim Integrated's MAX1551EZK+ Battery Charger

The MAX1551EZK+ from Maxim Integrated is a highly efficient, single-cell, lithium-ion (Li+) battery charger designed to simplify the charging process for portable electronic devices. This compact integrated circuit (IC) comes in a tiny 5-pin SOT23 package, making it an ideal choice for space-constrained applications such as handheld devices, wearables, and other portable gadgets.

One of the standout features of the MAX1551EZK+ is its proprietary thermal-regulation scheme, which ensures maximum charging rate without risk of overheating. This feature allows the charger to automatically adjust the charge current based on the temperature, thereby providing a safe charging environment for the battery and prolonging its life.

The device operates from a supply voltage range of 4.25V to 6.5V, which makes it versatile for various power sources, including standard USB ports and wall adapters. Its charging voltage is factory preset to 4.2V, which is suitable for most single-cell Li+ batteries. Additionally, the MAX1551EZK+ supports a programmable charge current up to 280mA, allowing users to tailor the charging to the specific needs of their application.

Another significant advantage of the MAX1551EZK+ is its simplicity. With minimal external components required, this charger can be easily integrated into a design. It includes an on-chip power MOSFET, eliminating the need for an external transistor. The IC also features a charge-status output that can be used to drive an LED indicator, providing visual feedback on the charging process.

For safety, the MAX1551EZK+ incorporates several protection features. It has a preconditioning charge mode for deeply discharged batteries, an automatic charge termination upon completion, and a safety timer for additional protection. The device also includes under-voltage lockout (UVLO), ensuring that the charger operates only when the input voltage is within an acceptable range.

In summary, the Maxim Integrated MAX1551EZK+ offers a compact, efficient, and easy-to-use solution for charging single-cell lithium-ion batteries. Its thermal regulation, programmable charge current, and integrated safety features make it a robust choice for designers looking to incorporate reliable battery charging capabilities into their portable devices.