Analog Devices Inc. LTC4440AIMS8E-5#TRPBF

Overview

LTC4440AIMS8E-5#TRPBF from Analog Devices (formerly Linear Technology) is a high-frequency, high-voltage, high-side N-channel MOSFET gate driver optimized for full-bridge and phase-modulated converter topologies. It operates with input supply voltages up to 80V (with 100V/100ms transient tolerance), delivers 1.1A peak pull-up current and 1.85Ω pull-down impedance at 6V BOOST–TS, and drives 1nF loads with 10ns rise and 7ns fall times - enabling efficient switching in telecom and server power supplies.

For engineers reviewing the LTC4440AIMS8E-5#TRPBF datasheet, LTC4440AIMS8E-5#TRPBF pinout, LTC4440AIMS8E-5#TRPBF application, or LTC4440AIMS8E-5#TRPBF equivalent, key selection criteria include its 80V TS-rail rating, supply-independent TTL/CMOS inputs with 350mV hysteresis, undervoltage lockout (3.04V falling threshold), thermally enhanced MSOP-8 package with exposed pad, and compatibility with standard-threshold logic-level FETs in isolated high-side gate drive roles.

Technical Context

The LTC4440AIMS8E-5#TRPBF employs a level-shifted input stage with internal voltage regulation to maintain stable VIH (1.55V typ) and VIL (1.25V typ) thresholds independent of VCC, coupled with 350mV hysteresis to suppress noise-induced false triggering. Its output stage integrates an NPN bipolar pull-up (Q1) and N-channel MOSFET pull-down (N1), delivering asymmetric drive strength optimized for fast turn-on and robust turn-off under high dv/dt conditions.

It supports bootstrap operation with BOOST–TS up to 95V continuous (115V/100ms), features integrated undervoltage lockout disabling TG when VCC falls below 3.04V, and is rated for –40°C to +125°C junction temperature. The device targets high-density, high-reliability DC/DC converters where gate drive integrity, transient immunity, and thermal performance are critical.

Key Specifications

Pinout & Package

The LTC4440AIMS8E-5#TRPBF is housed in an 8-lead plastic MSOP package (MS8E) with exposed thermal pad (Pin 9), requiring soldering to PCB ground for θ_JA = 40°C/W thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side gate driver applications.

Compared with LTC4440AIMS8E-5#TRPBF, LTC4444-5 adds shoot-through protection at the cost of narrower VCC range and higher minimum supply, while LTC4446 trades protection for higher drive capability - making LTC4440AIMS8E-5#TRPBF optimal for thermally constrained, transient-heavy full-bridge applications requiring proven reliability over added safety logic.

Availability

LTC4440AIMS8E-5#TRPBF is available at Aetrix Electronics and suitable for telecom power systems, server power supplies, and automotive 48V DC/DC converters requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for LTC4440AIMS8E-5#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 acquired Linear Technology in 2017 and maintains its high-performance analog and power IC portfolio with rigorous qualification and long-term product support.

The LTC4440A family was designed specifically for high-voltage, high-frequency synchronous rectification and full-bridge gate drive in isolated DC/DC converters - emphasizing transient robustness, thermal efficiency, and noise-immune logic interfacing.

FAQ

What is the maximum continuous voltage rating on the TS pin of the LTC4440AIMS8E-5#TRPBF?

The LTC4440AIMS8E-5#TRPBF supports a maximum continuous TS voltage of 80V, with absolute maximum rating of 100V for 100ms transients. This allows direct integration into 48V and 60V input power architectures while maintaining safe operating margins during line surges or inductive spikes. Operation beyond 80V continuous violates the specified operating range and risks reliability degradation.

Does the LTC4440AIMS8E-5#TRPBF require external level-shifting for TTL/CMOS input signals?

No, the LTC4440AIMS8E-5#TRPBF does not require external level-shifting. Its input stage features supply-independent TTL/CMOS-compatible thresholds (VIH = 1.55V, VIL = 1.25V typ) with 350mV hysteresis, enabled by an internal voltage regulator that stabilizes input buffer bias across the full 4V–15V VCC range. This allows direct connection to 3.3V or 5V logic controllers without additional components.

How does the undervoltage lockout (UVLO) function in the LTC4440AIMS8E-5#TRPBF?

The LTC4440AIMS8E-5#TRPBF incorporates an undervoltage lockout circuit that monitors VCC. When VCC falls below 3.04V (falling threshold), the internal buffer is disabled and the TG output is actively pulled down to TS. This prevents partial turn-on of the driven MOSFET, eliminating shoot-through risk and thermal stress during brownout or startup conditions. The UVLO hysteresis is 160mV, with rising threshold at 3.20V.

What is the purpose of the exposed pad (Pin 9) on the LTC4440AIMS8E-5#TRPBF MS8E package?

The exposed pad (Pin 9) on the LTC4440AIMS8E-5#TRPBF is electrically connected to GND and serves as the primary thermal path. When soldered to a 2500mm² double-sided 1oz copper PCB ground plane, it achieves θ_JA = 40°C/W. Failure to solder this pad results in significantly degraded thermal performance - potentially exceeding 100°C/W - leading to premature junction overheating and reduced reliability under sustained load.

Can the LTC4440AIMS8E-5#TRPBF drive both high-side and low-side N-channel MOSFETs?

Yes, the LTC4440AIMS8E-5#TRPBF can drive low-side N-channel MOSFETs when TS is connected to system GND, effectively converting it to a ground-referenced driver. In this configuration, BOOST–TS becomes a standard 4V–15V supply, and TG swings from GND to BOOST. The device's 1.1A pull-up and 1.85Ω pull-down remain fully effective, making it suitable for synchronous buck or half-bridge low-side drive where high sink current is needed to suppress Miller-induced turn-on.