LTC4240IGN - Hot Swap Controller from Linear Technology

The LTC4240IGN is a sophisticated hot swap controller designed by Linear Technology, now part of Analog Devices, to enable safe board insertion and removal from a live backplane. This integrated circuit (IC) provides a compact and reliable solution for managing the power supply to electronic components in high-availability systems, such as servers, data centers, and telecommunications equipment.

The LTC4240IGN is housed in a narrow SSOP-16 package, offering a space-efficient footprint for densely populated circuit boards. It operates from a supply voltage range of 2.7V to 16.5V, making it versatile for various applications. The controller allows a controlled ramp-up of the card supply voltage to prevent glitches on the power bus, inrush current, and system interference, thus protecting both the card and the backplane during hot-swap events.

One of the key features of the LTC4240IGN is its integrated 8.5V gate drive for an external N-channel MOSFET, which serves as the main power switch. This allows for efficient power control and distribution, while the MOSFET's low on-resistance minimizes power loss and heat generation. Additionally, the LTC4240IGN provides adjustable current limit, circuit breaker, and timer functions to further enhance system protection against overcurrent and short-circuit conditions.

The LTC4240IGN also includes a dV/dt control feature, which limits the voltage slew rate during hot swapping to reduce the risk of arcing and voltage spikes. Its multi-function status outputs can be used for signaling to a microcontroller or other monitoring devices to indicate fault conditions or successful power-up sequences.

With its built-in electronic circuit breaker, the LTC4240IGN can quickly disconnect the load in the event of a fault, and its automatic retry feature allows the system to attempt power restoration after a fault has been cleared. This self-recovery capability is essential for maintaining system uptime without the need for manual intervention.

In summary, the LTC4240IGN from Linear Technology is an advanced hot swap controller that ensures safe and efficient power management for electronic systems requiring hot-swap functionality. Its compact design, adjustable parameters, and robust protection features make it an ideal choice for engineers looking to enhance the reliability and serviceability of their high-availability systems.