LTC4266AIUHF-4#PBF

The LTC4266AIUHF-4#PBF is a Linear Technology (now Analog Devices) four-channel IEEE 802.3af/at PoE PD controller front-end. It provides the PoE power-detection, class/power negotiation, per-port current limiting, short-circuit protection, inrush control, undervoltage lockout, fault reporting, and hot-swap safety for four PoE ports. It typically works with external rectifiers, MOSFETs, and a DC-DC converter to deliver the PD output voltage. The “-4” denotes a four-port variant; “AIUHF” is the package/temperature/lead‑free code, and “#PBF” indicates Pb-free packaging. Use cases include four-port PoE PD front-ends for IP cameras, VoIP phones, wireless access points, or compact PoE switches. For exact pinout, electrical characteristics, and application diagrams, refer to the current datasheet and package specification on Analog Devices’ website.

Here are concise features of the LTC4266AIUHF-4#PBF (4-channel version):
- Four-channel hot-swap/power-path controller for protecting and distributing power to four rails.
- Independent current-limit on each channel (set via sense resistors) with controlled inrush and soft-start.
- Gate-drive control for external N-channel MOSFETs; supports pre-charge and fast turn-on/off.
- Comprehensive protection: overcurrent/short-circuit, overvoltage, undervoltage, reverse polarity, and thermal shutdown with latched fault and retry.
- Per-channel fault/status reporting (latchable faults and status outputs for MCU monitoring).
- Fault isolation and back-to-back/OR-ing capability across channels.
- Suitable for high-voltage/multi-rail backplanes with wide input range and low quiescent current.
- Pb-free packaging: AIUHF-4 (PBF).
Note: Verify exact electrical specs (voltage range, current limits, pinout) in the LTC4266AIUHF-4 datasheet for your application.

- Pin count: 40 pins (QFN/lead-free variant).
- Function: Quad hot-swap/high-side switch controller with four independent current-limited power paths, including fault/overcurrent protection and soft-start for multi-rail protection.

- Manufacturer: Analog Devices, Inc. (ADI). The LTC4266AIUHF-4#PBF part comes from Linear Technology, which ADI acquired in 2017.
- What kind of company: American multinational semiconductor company specializing in analog, mixed-signal, and signal-processing integrated circuits; a leading supplier of precision analog ICs and data converters.

Applications of LTC4266AIUHF-4#PBF:
- IEEE 802.3af/at PoE Powered Device (PD) interface
- Endspan and midspan PoE power designs
- Network endpoints: IP cameras, VoIP phones, wireless access points
- Industrial/Rugged PoE applications: remote sensors, controllers, telemetry
- PoE power front-ends with protection (surge, overvoltage) and current limiting
- Efficient isolated DC-DC conversion from PoE for downstream electronics
In short: PoE PD power management for powering remote network and industrial devices.

Pb-free, RoHS-compliant 28-pin TSSOP (Thin Shrink Small Outline Package).