Toshiba Semiconductor and Storage TB67S142FTG,EL

Overview

TB67S142FTG from Toshiba Electronic Devices & Storage Corporation is a clock-controlled, PWM chopping-type 2-phase unipolar stepping motor driver IC fabricated in BiCD process. It delivers up to 3.0 A per channel output current, supports 45 V VM supply and 84 V motor output voltage, and enables microstepping resolutions from full-step to 1/32-step - used in precision motion control for industrial automation actuators and optical positioning stages.

For engineers reviewing the TB67S142FTG datasheet, TB67S142FTG pinout, TB67S142FTG application, or TB67S142FTG equivalent, key selection considerations include its WQFN48 package thermal performance, integrated error detection (TSD/ISD), brake and standby modes, and external VREF-based current threshold tuning with 0.25 Ω typical low-side MOSFET on-resistance.

Technical Context

The TB67S142FTG implements a dual-channel PWM constant-current chopper architecture with independent N-ch MOSFET half-bridges per phase, driven by an internal oscillator whose fixed off-time is set via OSCM pin resistance. Its step resolution is controlled digitally through DMODE1/DMODE2 pins, supporting full, half(a), half(b), quarter, 1/8, 1/16, and 1/32 steps.

It integrates real-time protection functions including overcurrent detection (ISD) at 3.1–5.0 A per channel, thermal shutdown (TSD) at 140–170 °C junction temperature, and thermal alarm (ALM) at 120 °C ±15 °C with auto-recovery. All logic inputs accept 2.0–5.5 V high-level signals, and open-drain outputs (ERR, ALM, MO) require external pull-ups.

Key Specifications

Pinout & Package

Package: P-WQFN48-0707-0.50-003 (7 mm × 7 mm, 0.5 mm pitch, exposed thermal pad).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar unipolar stepping motor driver applications.

Compared with TB67S142FTG, TB67S149FTG extends microstepping capability while maintaining pin and thermal compatibility, whereas STSPIN220 trades integrated sensing for reduced feature depth and different grounding topology - both require PCB redesign and firmware adaptation.

Availability

TB67S142FTG is available at Aetrix Electronics and suitable for industrial CNC positioning, medical infusion pump actuation, optical lens autofocus systems, and automated test equipment fixtures requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for TB67S142FTG 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

Toshiba Electronic Devices & Storage Corporation designs high-reliability analog, power, and motor driver ICs for industrial, automotive, and consumer applications, with emphasis on integration, thermal robustness, and system-level protection.

The TB67S142FTG belongs to Toshiba's TB67S series of clock-controlled unipolar stepper drivers, engineered specifically for compact, thermally constrained motion control systems requiring programmable microstepping and embedded fault resilience.

FAQ

What is the maximum continuous output current supported by the TB67S142FTG?

The TB67S142FTG has an absolute maximum output current rating of 3.0 A per channel, but its practical continuous current depends on thermal design. With proper PCB copper area (4-layer board, exposed pad soldered), it sustains 1.5 A per channel continuously at 25 °C ambient. Derating applies above 25 °C at 32.8 mW/°C - so at 60 °C ambient, max usable current drops to ~1.2 A. Always verify junction temperature using the PD-Ta graph in the TB67S142FTG datasheet.

How does the TB67S142FTG implement microstepping, and which resolutions does it support?

The TB67S142FTG uses internal current DACs and PWM chopping to generate sinusoidal phase currents corresponding to selected step resolution. It natively supports full, half(a), half(b), quarter, 1/8, 1/16, and 1/32 steps - all configured via DMODE1 and DMODE2 logic inputs. Unlike some drivers, half(a) and half(b) provide distinct current waveforms for optimized torque linearity, and the 1/32 mode enables sub-degree angular resolution without external indexer hardware.

Can the TB67S142FTG drive bipolar stepper motors?

No, the TB67S142FTG is designed exclusively for unipolar stepper motors with center-tapped windings. Its output architecture consists of four independent N-channel MOSFETs (two per phase) referenced to VCOM, not complementary H-bridges. Attempting to connect a bipolar motor will result in incorrect phase excitation and potential device damage. For bipolar motors, Toshiba recommends the TB67S279FTG or similar H-bridge drivers.

What is the function of the VCOM pin on the TB67S142FTG, and how must it be connected?

The VCOM pin serves as the common reference node for unipolar motor center taps and internal current sensing. It must be connected directly to the center tap of both phase windings (A and B), and tied to the same low-impedance ground plane as RSGNDA and RSGNDB. Incorrect VCOM routing - such as daisy-chaining or routing through narrow traces - causes current imbalance, torque ripple, and inaccurate current regulation. The datasheet mandates single-point grounding of all GND-related pins on the PCB solder mask.

How do the ERR, ALM, and MO pins differ in functionality and electrical behavior on the TB67S142FTG?

All three pins are open-drain outputs requiring external 3.3 V or 5 V pull-up resistors (10–100 kΩ). ERR goes low only when TSD or ISD faults are latched and remains low until cleared by VM reset or standby mode toggle. ALM goes low upon reaching 120 °C ±15 °C and auto-recovers when temperature falls below ~90 °C. MO goes low only at electrical zero angle (e.g., after RESET assertion) and floats Hi-Z otherwise - enabling precise homing without encoder feedback. Each serves a distinct system-level monitoring purpose.