Texas Instruments UCC27325D

Overview

UCC27325D from Texas Instruments is a dual low-side MOSFET driver with one inverting and one noninverting output channel, delivering ±4 A peak gate drive current at the Miller plateau region, operating from 4.5 V to 15 V supply, and featuring TTL/CMOS-compatible inputs independent of VDD - used in high-frequency synchronous rectification and half-bridge gate drive stages.

For engineers reviewing the UCC27325D datasheet, UCC27325D pinout, UCC27325D application, or UCC27325D equivalent, key selection criteria include output logic configuration (INVA/OUTA, NONINVA/OUTB), SOIC-8 thermal performance (RθJA = 107.3°C/W), Miller-region drive capability, and compatibility with fast-switching power topologies requiring sub-40 ns propagation delay.

Technical Context

The UCC27325D implements a BiPolar–MOSFET hybrid output stage that enables simultaneous high-current sourcing and sinking even at low VDD (≥4.5 V), minimizing shoot-through risk while maintaining constant-current behavior during the Miller plateau. Its input stage features wide hysteresis and voltage-independent TTL/CMOS thresholds (VIN_H = 1.6–2.5 V, VIN_L = 0.8–1.5 V), ensuring noise immunity across temperature (–40°C to +125°C).

Each channel operates independently: OUTA is inverting (intended for P-channel MOSFETs), OUTB is noninverting (intended for N-channel MOSFETs); both outputs swing rail-to-rail (GND to VDD) and support paralleling for combined 8-A drive. The device lacks internal level-shifting or high-side capability and requires external gate resistors for controlled slew rate.

Key Specifications

Pinout & Package

UCC27325D is housed in an 8-pin SOIC (D) package measuring 4.90 mm × 3.91 mm, with exposed pad not connected internally. Pin functions are validated per TI SLUS492K Rev. K (Nov. 2023).

Key Features

Applications

Equivalent & Alternatives

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

Compared with UCC27324D and LM5113SD, the UCC27325D uniquely provides asymmetric logic configuration in a standard SOIC-8 footprint - enabling compact half-bridge control where one leg requires inversion (e.g., bootstrap gate timing) and the other does not, without adding external inverters or changing PCB layout.

Availability

UCC27325D is available at Aetrix Electronics and suitable for switch-mode power supplies, solar inverters, and motor control systems requiring stable component supply, long-term industrial lifecycle support, and guaranteed SOIC-8 packaging consistency.

Supply support for UCC27325D 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, designing analog, embedded processing, and power management ICs for industrial, automotive, and communications markets.

The UCC27325D belongs to TI's UCCx732x dual gate driver product line, engineered specifically for high-efficiency, high-frequency power conversion where robust Miller-region drive, logic flexibility, and thermal reliability are critical.

FAQ

What logic configuration does the UCC27325D implement?

The UCC27325D implements one inverting channel (INA → OUTA) and one noninverting channel (INB → OUTB). This mixed configuration supports asymmetric gate drive requirements - for example, driving a high-side P-channel MOSFET with inverted logic while simultaneously controlling a low-side N-channel MOSFET with direct logic. Both inputs accept TTL/CMOS levels independent of VDD, and unused inputs must be tied to VDD or GND.

Can the UCC27325D drive high-side MOSFETs directly?

No, the UCC27325D is a dedicated low-side driver only and cannot directly drive high-side N-channel MOSFETs due to lack of level-shifting or floating supply capability. It can drive high-side P-channel MOSFETs via its inverting OUTA output, or serve as the low-side driver in bootstrap-based high-side configurations. For true high-side N-channel drive, a dedicated high-side or half-bridge driver (e.g., UCC272xx) is required.

What is the maximum capacitive load the UCC27325D can drive reliably?

The UCC27325D is characterized for 1.8 nF load in datasheet switching specs, but real-world operation supports ≥10 nF loads with appropriate gate resistors. At 10 nF and 300 kHz, power dissipation reaches ~0.43 W - requiring careful thermal design in SOIC-8. For >15 nF loads, paralleling OUTA and OUTB (with split gate resistors) extends effective drive capability while maintaining edge integrity and minimizing channel skew.

Does the UCC27325D require external bypass capacitors?

Yes, the UCC27325D requires two VDD bypass capacitors: a 0.1 µF ceramic capacitor placed as close as possible to Pin 6 (VDD) and Pin 3 (GND), plus a ≥1 µF low-ESR bulk capacitor (e.g., tantalum or polymer) in parallel. This dual-capacitor network maintains low impedance across 100 kHz–100 MHz, preventing supply rail collapse during ±4 A transient current pulses and suppressing switching noise coupling into sensitive control circuitry.

How does the UCC27325D handle unused input pins?

Unused input pins (INA and INB) on the UCC27325D must never be left floating - doing so risks erratic output behavior and increased EMI susceptibility. Each unused input must be tied directly to either VDD (for logic HIGH) or GND (for logic LOW) using a low-inductance connection. Pull-up/pull-down resistors are not recommended; hard connection ensures deterministic state and eliminates noise-induced false triggering during system startup or fault conditions.