LTC4268IDKD-1

The LTC4268IDKD-1 is an Analog Devices (formerly Linear Technology) high-side hot-swap / power-path controller. It drives external N-channel MOSFETs to protect and manage a live DC power rail, enabling safe insertion/removal of boards and modules.
Key features:
- Inrush control with soft-start and programmable current limit (via sense resistor)
- Overcurrent/short-circuit protection
- Overvoltage and undervoltage protection
- Reverse-current blocking and surge protection
- Thermal shutdown and fault/status reporting
- External-MOSFET-based implementation; enable input and fault/status outputs
Package/temperature:
- “IDKD” denotes the industrial temperature variant in an 8-pin package (per datasheet).
Applications:
- Hot-swappable servers and telecom equipment
- DC power distribution and rail protection
- Redundant supply OR-ing and live-edge protection
How it works (at a glance):
- Detects rail insertion, throttles FETs with soft-start, continuously monitors voltage/current, clamps faults, and signals status via fault/flag outputs.
For exact specs (voltage range, current limit, pinout), refer to the LTC4268IDKD-1 datasheet.

Here are the typical features of the LTC4268IDKD-1 (hot-swap power controller family):
- High–side hot-swap controller with external pass-FET drive
- Programmable current limit (via sense resistor) with accurate control
- Inrush (soft-start) control to limit turn-on surge
- Discharge function on turn-off for fast output collapse
- Overvoltage and undervoltage protection
- Reverse-battery/reverse-current protection
- Overcurrent/thermal protection with fault indication
- Fault and status reporting pins for system monitoring
- Wide input/rail voltage range suitable for telecom/industrial rails
- 16-pin package (IDKD variant) with typical industry standard pinout
Note: exact specs (e.g., current-limit range, voltage range) are determined by the specific external components and the exact device revision; consult the LTC4268 datasheet for precise numbers.

LTC4268IDKD-1 is available in a 48-pin LQFP package (approximately 7x7 mm).

- Pin count: 8 pins.
- Function: IEEE 802.3af/at PoE PD controller with integrated high‑side switch (PoE power negotiation, protection, and regulate/drive for a PoE-powered device).

Manufacturer: Analog Devices, Inc. (AD), a global American multinational semiconductor company.
Company type: Specializes in analog, mixed-signal, and DSP integrated circuits; acquired Linear Technology (the LTC line) in 2017, and LTC parts are now part of Analog Devices.

- PoE PD interface and power-management for IEEE 802.3af/at powered devices.
- Typical applications: IP cameras, VoIP phones, wireless access points, network switches, PoE midspans/injectors, and industrial/remote sensing powered over Ethernet; includes line-side protection, inrush control, current limiting, and overvoltage/thermal protection for safe hot-swap.