DESCRIPTION
The S39421 is a fully integrated hot swap controller intended for use on add-in cards that may be inserted into or removed from powered-on host platforms. The S39421 performs a variety of tasks starting with the validation of proper card insertion and the presence of “in-spec” voltages at the host platform interface.

FEATURES
• Full Voltage Control for Hot Swap Applications
    – Card Insertion Detection
    – Platform Voltage Detection
    – Card Voltage Sequencing
    – 5 Volt, 12 Volt and 3.3 Volt
• 12 Volt FET Enable Outputs
    – Allows use of Low On-resistance N-Channel FETS
• Card Reset Generation Based on Out of Spec Voltages
    – Host Reset
• Programmable Slew Rate Control [250V/Sec Default Rate]
• Supports 5 Volt, 3.3 Volt and Mixed Voltage Cards
• Integrated 1K Bit E2PROM Memory
• Data Download™ Mode [Simplifies
    Downloading of Configuration Memory into Interface ASIC or MCU]