Texas Instruments UC1709L

Overview

UC1709L from Texas Instruments is a dual high-speed FET driver IC designed for fast turn-on/turn-off of power MOSFET gates in high-reliability military and aerospace systems. It delivers ±1.5 A peak source/sink drive, operates from 5 V to 40 V, achieves 40 ns rise/fall times into 1000 pF, and includes thermal shutdown protection - enabling robust gate driving in DC-DC converters and motor control stages.

For engineers reviewing the UC1709L datasheet, UC1709L pinout, UC1709L application, or UC1709L equivalent, key selection criteria include its LCCC-20 ceramic package, –55°C to +125°C operating junction temperature, TTL-compatible inverting inputs, and 2.0 V output saturation at ±500 mA - critical for high-temperature, radiation-tolerant, and hermetically sealed power stage designs.

Technical Context

The UC1709L uses a high-speed Schottky bipolar process with totem-pole output stages optimized to minimize cross-conduction current spikes during switching transitions. Its inverting logic inputs ensure full TTL compatibility while supporting rail-to-rail output swing over 30 V.

Thermal protection is implemented via internal junction-sense circuitry triggering shutdown at ~155°C, and the device features low quiescent current (7–12 mA) across its full operating range. Absolute maximum ratings confirm 40 V supply tolerance and ±1.5 A peak transient output capability in the LCCC package.

Key Specifications

Pinout & Package

LCCC-20 (FK) ceramic package: 8.89 mm × 8.89 mm, leadless, hermetically sealable, with 1.27 mm pitch and 20 terminals arranged in a square grid. Designed for high-reliability, high-temperature, and low-outgassing environments.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual high-speed FET driver applications.

Compared with UC1709J, the UC1709L offers superior thermal performance (θ_JC = 20°C/W vs. 28°C/W) and higher peak drive current, making it better suited for high-power density applications; versus UC1709-SP, it lacks radiation hardening but provides identical timing and drive capability at lower cost for non-space military use.

Availability

UC1709L is available at Aetrix Electronics and suitable for avionics power converters, military motor drives, spacecraft point-of-load regulators, and radiation-hardened test equipment requiring stable component supply across extended temperature and lifecycle demands.

Supply support for UC1709L 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and high-reliability components for industrial, automotive, and defense markets.

The UC1709L belongs to TI's legacy military-grade power driver family, engineered specifically for high-temperature, high-reliability gate driving in aerospace, defense, and space applications where hermeticity and parametric stability are non-negotiable.

FAQ

What is the operating temperature range of the UC1709L?

The UC1709L is rated for an operating junction temperature range of –55°C to +125°C, fully compliant with MIL-PRF-38535 Class B requirements. This specification is validated across all electrical parameters in the datasheet and applies to the LCCC-20 package under specified thermal mounting conditions. The UC1709L maintains guaranteed performance across this full range without derating, making it suitable for extreme-environment applications such as jet engine control electronics and satellite power systems.

Does the UC1709L support non-inverting logic configuration?

No, the UC1709L implements strictly inverting logic at both inputs - a HIGH input produces a LOW output and vice versa. This architecture is fixed in silicon and cannot be reconfigured. To achieve non-inverting behavior, external inversion (e.g., using a single gate from a 74LS04) must be added upstream of the UC1709L inputs. The datasheet confirms inverting functionality is inherent to the UC1709L design and shared across the UC1709/UC2709/UC3709 family.

What is the thermal resistance (θ_JC) of the UC1709L package?

The UC1709L in the LCCC-20 (FK) package has a junction-to-case thermal resistance (θ_JC) of 20°C/W, as documented in the Thermal Resistance Table of the SLUS196C datasheet. This value is derived per MIL-STD-1835B and assumes proper thermal interface to a heatsink or metal-core PCB. It enables 3 W power dissipation at TC = 25°C, supporting continuous operation in high-ambient environments when adequately heatsunk.

Can the UC1709L drive GaN or SiC FETs effectively?

Yes, the UC1709L is capable of driving enhancement-mode GaN and SiC FETs due to its ±1.5 A peak source/sink current, 40 ns switching speed into 1000 pF, and 30 V output swing capability. Its fast edge rates and low output impedance minimize gate charging time, while the 5 V to 40 V supply range accommodates common GaN/SiC gate drive voltage requirements. However, external negative turn-off bias or Miller clamp circuits may still be needed depending on the specific FET's threshold and dV/dt immunity.

Is the UC1709L RoHS-compliant?

No, the UC1709L is not RoHS-compliant. As confirmed in TI's Packaging Information addendum, the UC1709L uses SNPB (tin-lead) lead finish and is designated "No" under RoHS status. It is manufactured for military and aerospace applications where leaded finishes are mandated for reliability, solder joint integrity, and resistance to tin whisker formation. For RoHS-compliant alternatives, consider the UC2709DW or UC3709DW, which use NiPdAu or NIPDAU finishes.