Texas Instruments UCC27518DBVR

Overview

UCC27518DBVR from Texas Instruments is a single-channel, high-speed, low-side MOSFET/IGBT gate driver with inverting logic, 4-A peak source/sink symmetrical drive, 17-ns typical propagation delay, and 4.5-V to 18-V supply range - deployed in GaN-based DC-DC converters and solar inverters for robust switching control.

For engineers reviewing the UCC27518DBVR datasheet, UCC27518DBVR pinout, UCC27518DBVR application, or UCC27518DBVR equivalent, key selection criteria include CMOS-input threshold tracking VDD (55%/39% VDD), EN-pin TTL-compatible enable (2.1 V/1.25 V thresholds), UVLO protection (4.2 V turn-on with 300-mV hysteresis), and SOT-23-5 thermal performance (R_θJA = 217.6°C/W).

Technical Context

The UCC27518DBVR implements an inverting input architecture where IN− controls output state, with CMOS-input thresholds scaling linearly with VDD (VIN-H ≈ 55% VDD, VIN-L ≈ 39% VDD) and 16–19% VDD hysteresis for noise immunity. Its hybrid pull-up output stage combines N- and P-channel MOSFETs to deliver boosted 4-A peak sourcing during Miller plateau transitions.

Internal UVLO holds OUT low when VDD falls below 3.80 V (min) and releases at ≥4.20 V (typ), ensuring glitch-free startup/shutdown. The EN pin operates independently of VDD with fixed 2.1-V high/1.25-V low thresholds, enabling direct interfacing with 3.3-V or 5-V microcontrollers without level shifting.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, single-row 5-pin surface-mount, optimized for thermal dissipation on 2-layer PCBs with minimal copper area.

Key Features

Applications

Equivalent & Alternatives

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

Compared with UCC27519DBVR, the UCC27518DBVR provides inverted logic essential for current-mode control loops; compared with TPS2828DBVR, it delivers 40% faster propagation, scalable input thresholds, and enhanced thermal robustness - making it optimal for next-generation wide-bandgap power systems.

Availability

UCC27518DBVR is available at Aetrix Electronics and suitable for high-frequency GaN DC-DC converters, solar microinverters, and industrial motor drives requiring stable component supply across extended temperature and long product lifecycles.

Supply support for UCC27518DBVR 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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The UCC27518DBVR belongs to TI's UCC2751x family of high-speed low-side gate drivers, designed specifically to address timing-critical, high-efficiency power conversion using wide-bandgap semiconductors such as GaN and SiC.

FAQ

What is the logic configuration of the UCC27518DBVR?

The UCC27518DBVR features inverting logic: when the IN− pin is driven high, the OUT pin goes low, and vice versa. This behavior is hardwired and confirmed in the functional block diagram and pin description. Internal pull-down on IN− ensures safe low-state output when the input is floating - a key safety feature in fault-tolerant power designs. The UCC27518DBVR does not support noninverting operation; that function is implemented in the pin-compatible UCC27519DBVR.

Does the UCC27518DBVR require external pull-up or pull-down resistors on its input pins?

No, the UCC27518DBVR includes internal pull-down on the IN− pin and internal pull-up on the EN pin, eliminating need for external biasing. When IN− is left unconnected, the output remains low - a fail-safe condition verified in the "Output Held Low when Input Pins are Floating" feature. This design reduces component count and improves reliability in space-constrained layouts. External resistors are unnecessary unless specific RC delay networks are added for timing control.

What is the maximum operating frequency supported by the UCC27518DBVR?

The UCC27518DBVR itself has no intrinsic frequency limit; its usable switching frequency depends on external load (Q_g) and layout. With 4-A peak drive and 8-ns rise time into 1.8-nF load, it supports clean gate driving up to 1 MHz in GaN-based converters. At 500 kHz, typical supply current is ~8 mA (VDD = 12 V), confirming stable operation well beyond conventional 100–300 kHz SMPS ranges. Thermal limits (140°C T_J) and PCB copper area govern sustained high-frequency use.

How does the UCC27518DBVR handle undervoltage conditions on VDD?

The UCC27518DBVR incorporates internal UVLO circuitry that holds the OUT pin low whenever VDD drops below 3.80 V (min) during power-down or fails to reach 4.20 V (typ) during startup. Hysteresis of ~300 mV prevents oscillation near threshold. This behavior is explicitly guaranteed in the Electrical Characteristics table and ensures glitch-free operation in brownout scenarios - critical for compliance with IEC 62368 and UL 62368 safety standards in end equipment.

Can the UCC27518DBVR drive both MOSFETs and IGBTs effectively?

Yes, the UCC27518DBVR is explicitly characterized for both MOSFET and IGBT gate driving. Its 4-A symmetrical source/sink current, rail-to-rail output swing (VDD to GND), and low R_OL (0.5 Ω typ) provide strong turn-off immunity against Miller-induced dv/dt in IGBTs. For MOSFETs - especially GaN - the fast 8-ns rise time and low propagation delay (17 ns) minimize switching losses. TI's datasheet confirms validated operation with 50-nC GaN FETs and 330-nC IGBTs under 18-V VDD.