**LTC4359HDCB#TRMPBF: Ideal Diode Controller for High Availability Systems**

In the architecture of high availability systems, such as those found in telecommunications, data centers, and industrial automation, maintaining uninterrupted power is paramount. Voltage drops, power losses, and single points of failure introduced by traditional Schottky diodes in power path ORing applications present significant challenges. The **LTC4359HDCB#TRMPBF** from Analog Devices addresses these critical issues by functioning as an **ideal diode controller**, seamlessly replacing a power diode with a low-loss MOSFET to create a near-perfect diode with minimal forward voltage drop.

This controller operates by driving an external N-channel MOSFET to regulate the forward voltage drop across it to a mere **20mV**, a stark contrast to the typical 0.3V to 0.5V drop of a conventional Schottky diode. This drastic reduction translates into substantially lower power dissipation and reduced heat generation, enhancing overall system efficiency and reliability. The device is designed for high-side operation, which simplifies its integration into negative supply voltage systems.

A key feature of the LTC4359 is its **ultra-fast turn-off capability**. In the event of a reverse voltage condition, the controller can shut off the external MOSFET in less than **200ns**, preventing reverse current flow that could damage source supplies or drain system hold-up capacitors. This swift response is crucial for protecting sensitive electronics and ensuring seamless power source transitions without voltage glitches.

Furthermore, the LTC4359HDCB#TRMPBF offers robust protection and monitoring functions. It includes an **adjustable current limiting** feature to safeguard the MOSFET during overloads or short circuits. The part also provides a **status flag** that indicates whether the ideal diode is conducting, which is invaluable for system diagnostics and fault management. Its wide operating voltage range of 4V to 80V makes it exceptionally versatile for a broad spectrum of applications, from 12V automotive systems to 48V telecom racks.

Housed in a compact 8-lein DFN package, the device is optimized for high-density board layouts. The **TRMPBF** suffix denotes a tape and reel packaging, making it suitable for automated assembly processes in high-volume manufacturing.

ICGOODFIND: The LTC4359HDCB#TRMPBF stands out as a superior solution for constructing efficient and reliable power ORing circuits. By effectively emulating an ideal diode, it eliminates the inefficiencies and thermal management issues associated with physical diodes, making it an indispensable component for designers of high availability systems where power integrity is non-negotiable.

**Keywords:** Ideal Diode Controller, High Availability Systems, Power ORing, Low Forward Voltage, Reverse Current Protection