Texas Instruments UC2625Q

Overview

UC2625Q from Texas Instruments is a brushless DC motor controller IC designed for closed-loop speed control, braking, and safe direction reversal in industrial motor drives. It integrates high-side (50-V open-collector) and low-side (push-pull) gate drivers, a high-speed current-sense amplifier with ideal diode, latched soft-start, programmable cross-conduction protection, and tachometer output. It operates across –40°C to +105°C and supports two- or four-quadrant PWM operation for robotics and precision motion systems.

For engineers reviewing the UC2625Q datasheet, UC2625Q pinout, UC2625Q application, or UC2625Q equivalent, this page delivers verified technical context, exact pin functions, real-world motor control use cases, and validated alternative options - all grounded in TI's SLUS353C datasheet and official device specifications.

Technical Context

The UC2625Q implements fixed-frequency PWM motor control using an internal oscillator (35–65 kHz) set by ROSC and COSC, with RC-OSC providing a 1.2-Vpp ramp for voltage-mode or slope-compensated current-mode control. Its position decoder accepts three Hall sensor inputs (H1–H3) and DIR/SPEED-IN to generate six synchronized drive signals (PUA–PUC, PDA–PDC) with built-in 25–50 µs dead-time via shift-register latching.

Current sensing is dual-mode: pulse-by-pulse via ISENSE1/ISENSE2 differential input (gain ≈2 V/V, level-shifted 2.5 V), and average current sensing enabled in four-quadrant mode using RD. Over-current protection triggers at 0.20 V (peak) and 0.30 V (fail-safe shutdown), while OV-COAST provides overvoltage coasting with 0.1 V hysteresis.

Key Specifications

Pinout & Package

UC2625Q is packaged in a 28-pin PLCC (Q) format - same pinout as SOIC (DW) and LCC (L) variants per TI SLUS353C Figure 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar brushless DC motor controller applications.

Compared with UC3625Q, the UC2625Q offers extended industrial temperature capability without sacrificing functionality; compared with MP6532GQ-Z, it delivers full analog motor control integration - eliminating MCU dependency, reducing BOM count, and simplifying safety certification for standalone drives.

Availability

UC2625Q is available at Aetrix Electronics and suitable for industrial robotics, automated material handling, and medical motion systems requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for UC2625Q 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 power management technologies - with decades of expertise in motor control IC design and industrial-grade reliability validation.

The UC2625Q belongs to TI's UCx625 family of brushless DC motor controllers - engineered specifically for robust, self-contained analog motor control in harsh environments where deterministic timing, hardware safety features, and minimal external components are essential.

FAQ

What is the maximum supply voltage for UC2625Q?

The UC2625Q has an absolute maximum VCC rating of 20 V, but its functional operating range is specified from 10 V to 18 V. Operation above 18 V risks violating internal bias conditions and may cause erratic behavior or latch-up. The device includes under-voltage lockout that disables all outputs below 7.75 V to prevent partial turn-on of power stages. Always bypass VCC with a 0.1-μF ceramic capacitor directly to GND, and consider adding a 10-μF electrolytic for high-impedance supplies.

How does UC2625Q implement safe direction reversal?

The UC2625Q uses a hardware direction latch that only accepts DIR input changes when SPEED-IN voltage falls below 250 mV - indicating low motor speed. This ensures mechanical coast-down before commutation reversal. Internally, the DIR signal passes through a two-bit shift register clocked by the PWM oscillator, enforcing a 25–50 µs minimum delay between direction commands. Simultaneously, cross-conduction protection logic inhibits all outputs if latch input and output differ - preventing shoot-through during transition. These features are fully autonomous and require no external timing components.

Can UC2625Q drive N-channel MOSFETs on the high side?

Yes, UC2625Q can drive high-side N-channel MOSFETs, but not directly - its PUA/PUB/PUC outputs are 50-V open-collector, active-low drivers intended for P-channel devices or level-shifting circuitry. To drive N-channel MOSFETs, external high-voltage level-shifting techniques must be used: transformer-isolated gate drivers (e.g., UC3724/UC3725), optocouplers with ≥10 V boost supply, or cascode transistor stages. TI's SLUS353C Application Information (Figures 10–14) details proven topologies, including fast-switching transformer-coupled and optocoupled solutions compatible with UC2625Q's timing characteristics.

What is the purpose of the RC-BRAKE pin on UC2625Q?

The RC-BRAKE pin on UC2625Q serves dual functions: first, it sets tachometer pulse width via RT/CT timing network (T ≈ 0.67 × RT × CT); second, it enables active braking when pulled below 0.8–1.2 V threshold. In brake mode, UC2625Q turns off all high-side drivers (PUA–PUC), enables all low-side drivers (PDA–PDC), and disables TACH-OUT. Braking current is controllable only if ISENSE reflects braking current - requiring proper current-sense resistor placement (e.g., RD in Figure 9D). Without current sensing, braking is uncontrolled and may damage power devices.

Does UC2625Q support both two-quadrant and four-quadrant operation?

Yes, UC2625Q supports both modes via the QUAD SEL pin (Pin 22). When low, it enables two-quadrant operation: only low-side drivers (PDA–PDC) are PWM-chopped while high-side drivers remain on - resulting in efficient unidirectional current control with slow decay. When high, it enables four-quadrant operation: all six drivers are chopped, allowing bidirectional current flow and symmetric acceleration/deceleration - essential for servo positioning and regenerative braking. Note: QUAD SEL has no effect during brake mode.