Analog Devices Inc. LT4293IMS#TRPBF

Overview

LT4293IMS#TRPBF from Analog Devices is an LTPoE++/IEEE 802.3bt-compliant single-signature powered device (PD) interface controller in a 10-lead MSOP package, supporting up to 90W power delivery, featuring 5-event classification sensing, integrated signature resistor (24.4 kΩ), and T2P PSE-type indicator output for real-time power negotiation. It enables high-power outdoor security cameras and commercial displays with auxiliary supply override down to 9V.

For engineers reviewing the LT4293IMS#TRPBF datasheet, LT4293IMS#TRPBF pinout, LT4293IMS#TRPBF application, or LT4293IMS#TRPBF equivalent, key selection factors include PoE power class configurability (Classes 0–8), VPORT absolute maximum rating (100V), junction temperature range (–40°C to 85°C), and compatibility with external N-channel hot-swap MOSFETs for <1.5W dissipation at full load.

Technical Context

The LT4293IMS#TRPBF implements IEEE 802.3bt single-signature PD detection and classification using dual configurable pins (RCLASS/RCLASS++) to set class-specific current thresholds (e.g., 40 mA for Class 4–8), with precise 24.4 kΩ detection signature resistance and 1.0 V signature/class hysteresis window. Its T2P open-drain output encodes PSE-allocated power via duty-cycle modulation (25%/50%/75% or Hi-Z/Low-Z states) based on event count and AUX status.

It integrates undervoltage lockout (VHSON = 37 V typ, VHSOFF = 31 V typ), overtemperature protection (150°C TJMAX), and a charge-pump-driven HSGATE output capable of driving external N-MOSFET gates with ±22 µA pull-up current and 10–18 V open-circuit voltage - eliminating need for P-channel MOSFETs and enabling >95% end-to-end efficiency when paired with LT4321 ideal bridges.

Key Specifications

Pinout & Package

LT4293IMS#TRPBF uses a 10-lead plastic MSOP package (3.0 mm × 4.9 mm, 0.5 mm pitch) with GND on pins 1 and 5, and exposed thermal pad not present (unlike DFN variant). Pin functions are electrically isolated per datasheet Rev. 0 functional definitions and absolute maximum ratings.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar powered device interface controller applications.

Compared with LT4294IMS#TRPBF, LT4293IMS#TRPBF reduces component count and routing complexity for single-signature PDs, while compared with LT4275IMS#TRPBF it adds critical 90W negotiation, 5-event classification, and LTPoE++ PSE differentiation - making it the optimal choice for next-generation high-power PoE endpoints.

Availability

LT4293IMS#TRPBF is available at Aetrix Electronics and suitable for outdoor security camera systems, commercial information displays, and industrial wireless access points requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LT4293IMS#TRPBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, communications, automotive, and healthcare markets with precision power, signal chain, and interface solutions.

The LT4293IMS#TRPBF belongs to Analog Devices' Power over Ethernet (PoE) PD controller product line, designed specifically to enable high-efficiency, high-power, single-signature powered devices compliant with IEEE 802.3bt and LTPoE++ standards.

FAQ

What is the maximum power level supported by the LT4293IMS#TRPBF?

The LT4293IMS#TRPBF supports up to 90W power delivery as a single-signature powered device, corresponding to LTPoE++ Class 8 and IEEE 802.3bt Type 4. This is achieved through 5-event classification and configurable RCLASS/RCLASS++ resistors per Table 2 in the datasheet. The LT4293IMS#TRPBF does not require external power multiplexing or secondary controllers to reach this level.

How does the LT4293IMS#TRPBF differentiate between LTPoE++ and IEEE 802.3bt power sourcing equipment?

The LT4293IMS#TRPBF differentiates LTPoE++ and IEEE 802.3bt PSEs using its T2P output and RCLASS++ pin behavior during classification. When RCLASS++ is terminated to GND, the LT4293IMS#TRPBF enters LTPoE++ mode and responds to 3-event sequences with 75% T2P duty cycle, whereas IEEE 802.3bt PSEs trigger 4- or 5-event sequences with 50% or 25% T2P duty cycles - all decoded internally without MCU intervention.

Can the LT4293IMS#TRPBF operate with an auxiliary power supply below 12V?

Yes, the LT4293IMS#TRPBF supports auxiliary supply override as low as 9V via its AUX pin, which has a 6.3V threshold (6.1–6.5V) and 3.2–7µA hysteresis current. When VAUX exceeds this threshold, the LT4293IMS#TRPBF disables classification, disconnects the signature resistor, pulls HSGATE low, and asserts T2P to indicate maximum available power - enabling seamless transition from PoE to low-voltage auxiliary sources.

What package type and temperature grade does the LT4293IMS#TRPBF use?

The LT4293IMS#TRPBF uses a 10-lead plastic MSOP package (3.0 mm × 4.9 mm, 0.5 mm pitch) with operating junction temperature range of –40°C to 85°C (I-grade). It is distinct from the DFN variants (e.g., LT4293IDD#TRPBF) which feature an exposed thermal pad and wider temperature range options - the MSOP version prioritizes board-level reliability in space-constrained commercial applications.

Does the LT4293IMS#TRPBF require an external MOSFET, and what are the key gate drive specifications?

Yes, the LT4293IMS#TRPBF requires an external low-R_DS(ON) N-channel MOSFET controlled via its HSGATE pin. Key gate drive specs include: open-circuit voltage of 10–18 V relative to HSSRC, ±22 µA pull-up current, and 200 µA pull-down current. This architecture eliminates need for P-channel devices and enables efficient switching with FETs such as PSMN040-100MSE, as shown in the typical application diagram.