DESCRIPTION
The LTC®9111 is an IEEE 802.3cg compliant Single-Pair
Power over Ethernet (SPoE) Powered Device (PD) controller.
A wide 2.3V to 60V operating range capability with
polarity correction make the LTC9111 particularly well
suited for classification-based systems in building and
factory automation.
SCCP-based classification ensures full operating voltage
is applied by the Power Sourcing Equipment (PSE) only
when a valid PD is connected. The LTC9111 drives two
external N-channel MOSFET switches during classification
with micropower operation to minimize reservoir capacitor
requirements. An external N-channel MOSFET switch
isolates the output capacitance from the connector during
classification and inrush. A voltage supervisor enables the
external MOSFET when the PD input voltage exceeds the
ON voltage threshold for the configured class and after a
mandated delay. The EN output asserts after the controlled
GATE pin ramp-up. The MOSFET is disabled if the input
voltage drops below the OFF voltage threshold for the
configured class. The LTC9111 drives a pair of external
low-side N-channel MOSFETs with a low start-up voltage
of 1.6V for polarity correction with reduced power losses.

FEATURES
- IEEE 802.3cg Compliant
- Wide Input Voltage Range: 2.3V to 60V
- Supports Serial Communication Classification Protocol (SCCP)
- Wakeup Signature
- Integrated 3.5V Standby Regulator
- 150μA Maximum Current During Classification
- Drives Low-Side Bridge MOSFETs for Polarity Correction
- Charge Pump Enhances External N-Channel MOSFET
- Pin Programmable Class Configuration
- Available in 12-Pin MSOP and DFN 4mm × 3mm Packages

APPLICATIONS
- Building Automation
- Factory Automation
- Security Systems
- Traffic Control Systems