An adjustable current limit allows users to vary the current limit threshold under various loading conditions, such as disk drive spin-up to normal operation. The wide operating voltage and adjustable current limit differentiate the LTC4218 from other low-voltage Hot Swap Controllers on the market today.
The LTC4218 features are tailored for use in RAID, server, telecom (i.e., ATCA, AMC, uTCA) and industrial applications. The load current is monitored using the voltage sensed across a current sense register and adjusting the MOSFET’s gate-to-source voltage accordingly. A separate ISET pin allows users to adjust the 5% accurate (15mV) current limit threshold during startup and normal operation as needed. Meanwhile, current foldback and powergood circuitry ensure that the switch is protected from excessive load current and indicate whether a powergood condition is maintained. The LTC4218 also features current monitor and fault outputs, 2% accurate overvoltage and undervoltage protection, and an adjustable current limit timer. A dedicated 12V version (LTC4218-12) is also available, which contains preset 12V specific thresholds.
The LTC4218 has a variety of ordering options. Commercial (C) and industrial (I) versions support operating temperature ranges, from 0°C to 70°C and -40°C to 85°C respectively. The LTC4218 is available in a 16-lead SSOP, while the LTC4218-12 is available in a 16-lead 5mm x 3mm DFN, both of which are RoHS compliant.