The ISL6142/52 are 14 pin, negative voltage hot plug controllers that allow a board to be safely inserted and removed from a live backplane. Inrush current is limited to a programmable value by controlling the gate voltage of an external N-channel pass transistor. The pass transistor is turned off if the input voltage is less than the Under-Voltage threshold, or greater than the Over-Voltage threshold. The PWRGD/PWRGD outputs can be used to directly enable a power module. When the Gate and DRAIN voltages are both considered good the output is latched in the active state.

The IntelliTrip™ electronic circuit breaker and programmable current limit features protect the system against short circuits. When the Over-Current threshold is exceeded, the output current is limited for a time-out period before the circuit breaker trips and shuts down the FET. The time-out period is programmable with an external capacitor connected to the CT pin. If the fault disappears before the programmed time-out, normal operation resumes. In addition, the IntelliTrip™ electronic circuit breaker has a fast Hard Fault shutdown, with a threshold set at 4 times the Over-Current trip point. When activated, the GATE is immediately turned off and then slowly turned back on for a single retry.

The IS+, IS-, and IS_OUT pins combine to provide a load current monitor feature that presents a scaled version of the load current at the IS_OUT pin. Current to voltage conversion is accomplished by placing a resistor (R9) from IS_OUT to the negative input (-48V).

• Operates from -20V to -80V (-100V Absolute Max Rating)
• Programmable Inrush Current
• Programmable Time-Out
• Programmable Current Limit
• Programmable Over-Voltage Protection
• Programmable Under-Voltage Protection
  • 135 mV of hysteresis ~4.7V of hysteresis at the power supply
• V_DD Under-Voltage Lock-Out (UVLO) ~ 16.5V
• IntelliTripTM Electronic Circuit Breaker distinguishes between severe and moderate faults
  • Fast shutdown for short circuit faults with a single retry (fault current > 4X current limit value).
• FAULT pin reports the occurrence of an Over-Current Time-Out
• Disable input controls GATE shutdown and resets Over-Current fault latch
• Load Current Monitor Function
  • IS_OUT provides a scaled version of the load current
  • A resistor from IS_OUT to -V_IN provides current to voltage conversion
• Power Good Control Output
  • Output latched "good" when DRAIN and GATE voltage thresholds are met.
  • PWRGD active low: ISL6142 (L version)
  • PWRGD active high: ISL6152 (H version)

• VoIP (Voice over Internet Protocol) Servers
• Telecom systems at -48V
• Negative Power Supply Control
• +24V Wireless Base Station Power