**LT1513-2IT7#PBF: A Comprehensive Guide to the 500kHz 2A Battery Charging IC**

In the realm of power management and battery charging solutions, Linear Technology's (now part of Analog Devices) **LT1513-2IT7#PBF** stands out as a highly versatile and robust integrated circuit. This IC is specifically engineered to address the complex demands of modern battery charging applications, offering a unique combination of high efficiency, compact design, and precise control. As a **constant-current, constant-voltage battery charger**, it is an ideal choice for charging Lithium-ion (Li-ion), Nickel-Cadmium (NiCd), and Nickel-Metal Hydride (NiMH) batteries from a wide variety of input sources.

**Key Features and Technical Specifications**

The core of the LT1513's functionality lies in its **high-frequency 500kHz current-mode switching architecture**. This high switching frequency is a critical advantage, as it allows the use of remarkably small inductors and capacitors, significantly reducing the overall footprint of the printed circuit board (PCB). This makes it exceptionally suitable for space-constrained portable devices.

A standout feature of this IC is its **internal 2A, 60V power switch**. The integration of a high-voltage switch simplifies the external circuitry and enhances the system's reliability. It can handle input voltages up to 30V, providing ample headroom for various adapters and automotive power systems. The device is capable of delivering a precise **2A maximum charge current**, which is programmable using a single external resistor. This programmability offers designers the flexibility to tailor the charging current to the specific capacity and requirements of the target battery.

Furthermore, the LT1513 incorporates a **smart thermal regulation loop**. This advanced feature protects the IC by automatically reducing the charge current if the junction temperature exceeds approximately 145°C. This ensures robust operation under high ambient temperatures or high power dissipation conditions, preventing thermal runaway and enhancing long-term reliability.

**Application Circuit and Operation**

The typical application circuit for the LT1513 is notably simple and requires a minimal number of external components. The design primarily revolves around configuring the IC for the desired battery chemistry and charge termination method.

For Li-ion batteries, the charger operates in a **constant-current/constant-voltage (CC/CV) profile**. The constant-voltage level is set by a resistive divider network connected to the feedback (FB) pin, typically programmed for 4.2V per cell. The constant-current level is set by the voltage across a sense resistor (R_sense) between the Vc and Sense pins. The IC also supports programmable end-of-charge (C/10) detection for NiCd and NiMH batteries, where the charger terminates once the current drops to a predefined fraction of the initial fast-charge current.

**Design Advantages and Considerations**

* **High Efficiency:** The switching topology, combined with a low dropout internal switch, ensures high efficiency across a wide range of input and battery voltages. This minimizes heat generation and maximizes battery life.

* **Input Supply Flexibility:** Its wide input voltage range makes it compatible with 12V automotive systems, 24V industrial supplies, and common 5V-20V wall adapters.

* **Precision Charging:** The accurate 1% voltage reference for the feedback loop guarantees that the battery is charged to the exact voltage required, which is paramount for safety and longevity, especially for Li-ion chemistries.

* **Package:** The LT1513-2IT7#PBF is offered in a **7-lead TO-220 package**, which provides excellent thermal performance, allowing it to dissipate heat effectively even when operating at the full 2A charge current.

**ICGOODFIND**

ICGOODFIND summarizes the LT1513-2IT7#PBF as a high-performance, flexible, and resilient battery charging IC. Its integrated high-voltage switch, high-frequency operation, and comprehensive protection features make it an superior choice for designers seeking to create efficient, compact, and reliable battery charging systems for a broad spectrum of portable and industrial applications.

**Keywords:**

Battery Charger IC

Constant-Current Constant-Voltage

500kHz Switching Frequency

2A Charge Current

LT1513-2IT7#PBF