LTC4255 Datasheet | Linear Technology

.. LTC4255 Quad Network Power Controller with I2C patible Interface Features s s DESCRIPTIO s s s s s s Controls Four Independent - 48V Power Channels Each Channel has Separate Relay Drivers, ON/OFF Control, Short-Circuit Protection with Current Foldback, Open-Circuit Detection, and Power Good Indication Programmed via I2CTM patible Interface Five Bit Programmable Digital Address Allows Control of up to 32 LTC4255s (128 Channels) Interrupt on FAULT Output can be used to Eliminate Software Polling Programmable Current Limit and Open-Circuit Duration Periods Programmable Latchoff or Autoretry after Short Circuit Faults Programmable Autoretry Duty Cycle The LTC®4255 is a quad - 48V network power controller with independent relay drivers and I2C patible interface. Each channel can be turned on and off via software control, while providing short-circuit protection, opencircuit detection, and power good indication. The shortcircuit protection includes a current foldback feature to reduce power dissipation in the switch during shorts and start-up. The serial interface allows up to 128 channels to be controlled with only two digital lines. A FAULT output can be used as an interrupt line to eliminate fault detection by software polling. External switches and current sense resistors allow easy scaling of current and power dissipation levels and provide the maximum protection against voltage and current spikes. The LTC4255 is available in the 28-pin SSOP package. , LTC and LT are registered trademarks of Linear Technology Corporation. I2C is a trademark of Philips Electronics N.V. U APPLICATIO S s s IP Phone Systems DTE Power Distribution TYPICAL APPLICATIO 12V 0.1µF VCC SCL SDA FAULT AD0 AD1 AD2 AD3 AD4 DGND AGND VEE SENSE1 GATE1 RELAY3 RELAY4 OUT1 SENSE2 GATE2 OUT2 SENSE3 GATE3 OUT3 SENSE4 GATE4 OUT4 100k Q1 RS2 0.33Ω Q2 RS3 0.33Ω Q3 Q1, Q2, Q3, Q4: FDC3612 RELAYS: V23079 SERIES RS4 0.33Ω Q4 4255f - 48V RS1 0.1µF...