ADM1278-3ACPZ-RL

Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

Hot-swap controllers are integrated circuits used to safely manage electromechanical loads, by automatically controlling the power delivered to the load or system. The ADM1278-3ACPZ-RL is a hot-swap controller with a single fixed switching threshold. This device controls inrush currents for specified rise times, allowing for increased power handling capability on the primary side, with protection for the connected load on the secondary side of the bulk capacitors. It features integrated input current and temperature sensors, allowing it to switch the N-Channel MOSFET at the optimum point.

Application Field

The ADM1278-3ACPZ-RL is designed to control the inrush current for Hot Swap power modules, enabling them to manage multiple loads with varying input voltage and inrush current requirements. The device includes robust protection features against both current and thermal overstresses. It is suitable for applications where the load voltage must be powered up in a controlled manner, such as in server equipment, automotive ECU systems and industrial computer applications.

Working Principle

The ADM1278-3ACPZ-RL is an adaptive hot-swap controller that regulates the inrush current by sensing both the input voltage and current. During startup, the CF latch (Current-Foldback) is tripped, and the device enters a foldback current mode in order to reduce the inrush current. When the input voltage drops below 3.2V, the latch is reset and the device re-enters normal mode. During the overload condition, the IC turns off the MOSFET and turns on an internal N150 / N300 current source, which regulates the current drop to the foldback current level.

The device features an integrated temperature monitoring system consisting of NTC and PTC components. When the temperature reaches the upper threshold, the MOSFET is turned off and the output voltage de-rates. The operation of the thermal system is monitored through the TRIAL output, which is asserted low when the thermal system is in fault mode. When the temperature returns to normal, the MOSFET is turned back on, and the TRIAL output is asserted high.

The INT output of the device can be used to detect both input voltage, overvoltage and undervoltage conditions. It is asserted high on the rising edge of the input voltage, and remains low until the difference between the input voltage and threshold voltage is more than 10% of the threshold voltage. When the input voltage drops below the undervoltage threshold, the INT output remains low until the difference rises above the specified 10% threshold.

The ADM1278-3ACPZ-RL enables a system designer to implement a soft-start capability in order to limit the inrush current. Once the integrated PWM generator finishes, the Soft-Start (SS) pin is pulled low, turning off the MOSFET and limiting the inrush current. When the input voltage reaches the overvoltage threshold, the SS pin goes high, turning on the MOSFET, and allowing the system to operate normally.

The ADM1278-3ACPZ-RL also includes an Enable and a Reset pin, both of which must be asserted high in order for the device to be enabled. The Reset pin is used to reset the internal latch once the overvoltage condition goes away. The Enable pin can be used to disable the device for further diagnostic purpose, or for system shutdown.

In summary, the ADM1278-3ACPZ-RL Hot Swap Controller is designed to provide the system designer with a safe, dependable and easily implementable solution for hot-swapping electronic devices. It offers robust protection against current and thermal overloads, along with an integrated Soft-Start feature, enabling the controlled start-up of multiple loads. The device can be easily employed in a wide range of applications requiring both power control and monitoring.

The specific data is subject to PDF, and the above content is for reference