Date: 02/07/2010

5 Amp hot swap controller from Linear

Linear has unveiled the LTC4219, a 5A Hot Swap controller for protecting low power boards with load supply voltages ranging from 2.9V to 15V. This controller allows a board to be safely inserted and removed from a live backplane by limiting the amount of inrush current to the load supply during power up.

Some of the main features of LTC4219 are:
1. Consists of an integrated a power MOSFET and sense resistor in its power path to limit inrush current.
2. The device's internal dV/dt circuit means there is no need for an external gate capacitor.
3. It has an adjustable current limit, therefore the allows users to vary the current limit threshold under different loading conditions, for example in disk drive spin-up to normal operation.
4. This controller is suggested for a wide range of RAID, server, telecom and industrial applications, especially in compact boards utilizing technologies like Fibre Channel where power is typically limited to less than 25W due to their small size and inability to dissipate large amounts of heat.
5. During start-up, inrush currents are controlled by limiting the gate ramp rate to a safe 0.3V/ms.
6. Load current is monitored using the voltage sensed across the internal 7.5mOhm sense resistor and adjusting the internal 33mOhm MOSFET gate-to-source voltage accordingly.
7. A separate ISET pin enables adjustment of the 10% accurate (5A) current limit threshold during start- up and normal operation as needed.
8. The current foldback and power-good circuitry ensure that the switch is protected from excessive load current and indicate whether or not healthy power conditions are maintained.
9. The LTC4219 also features current, temperature and fault outputs, as well as an adjustable current limit timer.


Package: RoHS-compliant, 16-pin 5mm x 3mm DFN

Price: starting at each US$3.35 in 1,000 piece quantities.

Availablity:
The LTC4219 is available as a dedicated 12V (LTC4219-12) or 5V (LTC4219-5) version, which contain preset 12V/5V-specific thresholds.

For more information visit: www.linear.com/pr/4219