Analog Devices Inc. LTC4444EMS8E#PBF

Overview

LTC4444EMS8E#PBF from Analog Devices is a high-frequency, high-voltage synchronous N-channel MOSFET gate driver for buck and buck-boost converters, supporting up to 100V input voltage, 7.2–13.5V VCC supply, and bootstrapped high-side operation up to 114V above ground. It delivers 2.5A peak TG pull-up and 3A peak BG pull-up current with adaptive shoot-through protection, enabling efficient switching in telecom and automotive power supplies.

For engineers reviewing the LTC4444EMS8E#PBF datasheet, LTC4444EMS8E#PBF pinout, LTC4444EMS8E#PBF application, or LTC4444EMS8E#PBF equivalent, key selection criteria include bootstrap voltage tolerance (≤114V), dual independent inputs with level-shifting, undervoltage lockout thresholds (6.15V/6.6V), thermal performance in MS8E package, and compatibility with high-gate-charge N-MOSFETs in synchronous DC/DC topologies.

Technical Context

The LTC4444EMS8E#PBF integrates CMOS-compatible input buffers with 450mV hysteresis (VIH = 2.75V, VIL = 2.3V) referenced to GND, enabling noise-immune control of high- and low-side N-MOSFETs. Its internal level shifter translates TINP logic to the bootstrapped domain, allowing TG output to swing between TS and BOOST.

Adaptive shoot-through protection monitors TS voltage and input timing to prevent simultaneous conduction: if BINP remains high when TINP rises, TG activation is delayed until BG turns off; if TS stays high after TINP falls, BG enables only after 150ns. The driver also features integrated UVLO (6.15V falling, 6.6V rising) and thermal shutdown (>160°C).

Key Specifications

Pinout & Package

The LTC4444EMS8E#PBF uses an 8-lead MSOP package (MS8E) with exposed thermal pad (Pin 9 = GND), requiring soldering to PCB ground for θJA = 40°C/W. Pin 5 is NC; all other pins are functionally defined and electrically validated per Analog Devices Rev. C datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4446 and LTC4440, the LTC4444EMS8E#PBF uniquely combines 100V input capability, integrated adaptive shoot-through protection, and 114V bootstrap tolerance-making it the only option among the three qualified for AEC-Q100 automotive applications and capable of direct replacement in 72V+ telecom buck designs without layout or controller changes.

Availability

LTC4444EMS8E#PBF is available at Aetrix Electronics and suitable for distributed power architectures, automotive power supplies, and high-density power modules requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant performance.

Supply support for LTC4444EMS8E#PBF 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 precision instrumentation, industrial automation, communications, and automotive markets.

The LTC4444EMS8E#PBF belongs to Analog Devices' high-voltage power management IC portfolio, designed specifically for efficient, reliable gate driving in synchronous DC/DC converters operating up to 100V input with stringent EMI and thermal constraints.

FAQ

What is the maximum allowable BOOST–TS voltage for the LTC4444EMS8E#PBF?

The absolute maximum BOOST–TS voltage for the LTC4444EMS8E#PBF is 114V, as specified in the Absolute Maximum Ratings table. This rating enables safe operation in 100V-input synchronous buck converters with sufficient margin for transients and ripple. Exceeding this voltage risks permanent damage to the high-side level shifter and output stage. Designers must ensure the bootstrap capacitor and diode are rated accordingly and that TS node ringing does not cause instantaneous overvoltage.

Does the LTC4444EMS8E#PBF require external bootstrap diode and capacitor?

Yes, the LTC4444EMS8E#PBF requires an external bootstrap diode connected between VCC (Pin 3) and BOOST (Pin 6), and an external capacitor between BOOST (Pin 6) and TS (Pin 8). The diode must withstand reverse voltage ≥VIN and forward current sufficient to recharge the capacitor each cycle. Typical values are 10–100nF ceramic capacitor and Schottky diode (e.g., MMDL770T1G). Omitting either component prevents high-side gate drive functionality.

How does adaptive shoot-through protection work in the LTC4444EMS8E#PBF?

The LTC4444EMS8E#PBF implements adaptive shoot-through protection by monitoring the TS pin voltage and input timing relationships. If BINP remains high when TINP rises, TG activation is blocked until BG fully turns off. If TS remains high after TINP falls, BG is delayed by 150ns before enabling. This dynamic response eliminates fixed dead-time tuning and prevents cross-conduction without sacrificing efficiency-unlike static dead-time schemes that waste conduction time or risk shoot-through under varying load/temperature conditions.

Is the LTC4444EMS8E#PBF AEC-Q100 qualified?

Yes, the LTC4444EMS8E#PBF is AEC-Q100 qualified for automotive applications, as confirmed in the Rev. C datasheet revision history and ordering information table. It is rated for –40°C to 125°C junction temperature and manufactured under controlled automotive processes. Only versions with the #W suffix (e.g., LTC4444EMS8E#WPBF) are designated for automotive use; the #PBF variant meets AEC-Q100 requirements but is intended for industrial applications unless explicitly certified for automotive deployment.

What thermal considerations apply to the LTC4444EMS8E#PBF MS8E package?

The LTC4444EMS8E#PBF's MS8E package relies on soldering the exposed thermal pad (Pin 9) to a PCB ground plane to achieve θJA = 40°C/W. Failure to do so increases thermal resistance significantly-potentially exceeding 100°C/W-and risks junction overheating above 150°C. For 1.2W dissipation at 125°C ambient, a minimum 2500mm² double-sided 1oz copper area is recommended. Thermal vias under the pad and proper ground plane stitching are essential for sustained high-current operation.