ISL6161

Features:

• HOT SWAP Dual Power Distribution and Control for +12V and +3.3V
• Provides Fault Isolation
• Programmable Current Regulation Level
• Programmable Time Out
• Charge Pump Allows the Use of N-Channel MOSFETs
• Power Good and Over Current Latch Indicators
• Adjustable Turn-On Ramp
• Protection During Turn-On
• Two Levels of Current Limit Detection Provide Fast Response to Varying Fault Conditions
• 1s Response Time to Dead Short
• 3s Response Time to 200% Current Overshoot
• Pb-free available




Application

• PCI-Express Applications
• Power Distribution and Control
• Hot Plug, Hot Swap Components




Pinout






Specifications

TA = 25
V_DD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to +16V
12VG, C_PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 21V
12VISEN, 12VS . . . . . . . . . . . . . . . . . . . . . . . . . . -5V to V_DD + 0.3V
3VISEN, 3VS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -5V to 7.5V
PGOOD, R_ILIM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7.5V
ENABLE, C_TIM, 3VG . . . . . . . . . . . . . . . . . . . . . -0.3V to V_DD + 0.3V
ESD Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . 2kV (Class 2)




Description

The ISL6161 is a HOT SWAP dual supply power distribution controller that can be used in PCI-Express applications. Two external N-Channel MOSFETs are driven to distribute and control power while providing load fault isolation. At turn-on, the gate of each external N-Channel MOSFET is charged with a 10A current source. Capacitors on each gate (see the Typical Application Diagram on page 1), create a programmable ramp (soft turn-on) to control in-rush currents. A built-in charge pump supplies the gate drive for the 12V supply N-Channel MOSFET switch. Overcurrent protection is facilitated by two external current sense resistors and FETs. When the current through either resistor exceeds the user programmed value, the controller enters the current regulation mode. The time-out capacitor, CTIM, starts charging as the controller enters the time-out period. Once CTIM charges to a 2V threshold, both the N-Channel MOSFETs are latched off. In the event of a hard and fast fault of at least 3x the programmed current limit level, the N-Channel MOSFET gates are pulled low immediately before entering the time-out period. The controller is reset by a rising edge on the ENABLE pin. The ISL6161 constantly monitors both output voltages and reports either one being low on the PGOOD output as a low. The 12V PGOOD Vth is ~10.8V and the 3.3V Vth is ~2.8V nominally.