Data Sheet
LTC9101-2/LTC9102
12/24-Port IEEE 802.3bt PoE PSE Controller
FEATURES
DESCRIPTION
► Fully Compliant IEEE 802.3bt Type 3 and 4 PSE
► Up to 24 PSE Ports with Two Power Channels per Port
► +80V/–20V Tolerant Port-Facing Pins
► ECC-Protected eFlash and Data RAMs
► Low Power Path Dissipation per Channel
► 100mΩ Sense Resistance
The LTC®9101-2/LTC9102 chipset is a 12/24-port power sourcing
equipment (PSE) controller designed for use in IEEE 802.3bt
Type 3 and 4 compliant Power over Ethernet (PoE) systems.
The LTC9101-2/LTC9102 is designed to power compliant 802.3af,
802.3at, and 802.3bt PDs. The LTC9101-2/LTC9102 chipset de-
livers lowest-in-industry heat dissipation by utilizing low RDS(ON)
external MOSFETs and 0.1Ω sense resistance per power channel.
A transformer-isolated communication protocol replaces expensive
opto-couplers and a complex isolated 3.3V supply, resulting in
significant BOM cost savings.
► 30mΩ or Lower MOSFET RDS(ON)
► Chipset Provides Electrical Isolation
► Eliminates Optos and Isolated 3.3V Supply
► Very High Reliability Multipoint PD Detection
► Connection Check Distinguishes Single-Signature and
Dual-Signature PDs
► Continuous Per-Port Voltage and Current Monitoring
► 1MHz I2C Compatible Serial Control Interface
► Pin or I2C Programmable PD Power
► Available in a 24-Lead 4mm × 4mm (LTC9101-2) and 64-Lead
7mm × 11mm (LTC9102) QFN Packages
Advanced power management features include per-port 14‑bit cur-
rent/voltage monitoring, programmable power limits, and versatile
fast shut down of preselected ports. An advanced power manage-
ment host software layer is available. PD detection uses a propri-
etary multipoint detection mechanism ensuring excellent immunity
from false PD identification. Autoclass and 5-event physical classi-
fication are supported. The LTC9101-2/LTC9102 includes an I2C
serial interface operable up to 1MHz. The LTC9101-2/LTC9102 is
pin or I2C programmable to negotiate PD delivered power up to
71.3W.
APPLICATIONS
► PoE PSE Switches/Routers and Midspans
TYPICAL APPLICATION
Figure 1. 802.3bt 4-Pair Application, 1 Port Shown
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable "as is". However, no responsibility is assumed by Analog
Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to
change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
DOCUMENT FEEDBACK
TECHNICAL SUPPORT