Toshiba Semiconductor and Storage TB62261FTAG,EL

Overview

TB62261FTAG from Toshiba Electronic Devices & Storage Corporation is a two-phase bipolar stepping motor driver IC using PWM chopper control with PHASE-in interface logic. It delivers 1.2 A typical output current per phase at up to 35 V VM supply, features integrated thermal shutdown (TSD) and over-current detection (ISD), and supports full/half/quarter-step resolution for precision motion control in compact industrial actuators.

For engineers reviewing the TB62261FTAG datasheet, TB62261FTAG pinout, TB62261FTAG application, or TB62261FTAG equivalent, key selection considerations include its 0.8 Ω (typ.) high-side + low-side MOSFET on-resistance, external OSCM frequency tuning via R/C network, VREF-based current threshold setting, and QFN36 package thermal management requirements.

Technical Context

The TB62261FTAG implements a mixed-decay PWM chopper architecture with three-mode transistor control (CHARGE/SLOW/FAST) per H-bridge leg, enabling precise constant-current regulation across step resolutions. Its dual-channel design includes independent VREF_A/VREF_B pins for asymmetric current tuning and dedicated RS_A/RS_B sense inputs with 27 µA max bias current.

Motor phase sequencing is determined by PHASE_A/PHASE_B and IN_A1/IN_A2/IN_B1/IN_B2 logic states, with real-time zero-current detection triggering Hi-Z output during decay transitions. The internal oscillator (fOSCM = 1.2–2.0 MHz, configurable via OSCM pin) feeds a 1/16 divider to set chopper frequency between 40–150 kHz, balancing ripple suppression and thermal efficiency.

Key Specifications

Pinout & Package

P-WQFN36-0606-0.50-002: 6 mm × 6 mm, 0.5 mm pitch, exposed thermal pad - requires PCB GND connection on all four corners and center pad for effective heat dissipation (R_θJA = 96 °C/W on 4-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bipolar stepper motor driver applications.

Compared with STSPIN220TR and MP6500GQZ-P, the TB62261FTAG offers unique per-channel VREF tuning and external chopper frequency control-critical for optimizing torque consistency across varying motor inductances and thermal environments-while maintaining pin compatibility within Toshiba's QFN36 stepper driver family.

Availability

TB62261FTAG is available at Aetrix Electronics and suitable for industrial CNC positioning, medical infusion pump actuation, automated retail vending mechanisms, and lab automation sample carousels requiring stable component supply and long-term production continuity.

Supply support for TB62261FTAG 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 semiconductor solutions for industrial, automotive, and consumer applications, with expertise in BiCD process technology and motor control IP.

The TB62261FTAG belongs to Toshiba's bipolar stepper driver product line, engineered specifically for compact, thermally constrained motion systems requiring precise current regulation, integrated protection, and flexible step resolution without external controllers.

FAQ

What is the maximum continuous output current supported by the TB62261FTAG?

The TB62261FTAG supports 1.2 A typical continuous output current per phase under standard operating conditions (Ta = 25°C, VM = 24 V, 4-layer PCB). Absolute maximum rating is 1.5 A, but sustained operation above 1.2 A requires careful thermal design-including exposed pad soldering to GND and copper pour-to prevent TSD activation at junction temperatures exceeding 145°C.

How does the TB62261FTAG implement current regulation without external current-sense amplifiers?

The TB62261FTAG uses an internal current-comparison architecture that monitors voltage drop across external low-value shunt resistors (RS_A1/RS_A2 and RS_B1/RS_B2) connected to its dedicated sense pins. With a fixed 1/5.0 VREF gain, it compares this sensed voltage against the VREF_A/VREF_B reference to generate PWM duty cycle adjustments-eliminating need for external op-amps or comparators while maintaining ±5% current accuracy.

Can the TB62261FTAG drive unipolar stepper motors?

No, the TB62261FTAG is designed exclusively for two-phase bipolar stepper motors. Its H-bridge output stage (OUT_A+/OUT_A− and OUT_B+/OUT_B−) requires center-tap–free windings and cannot interface with unipolar motors' five- or six-wire configurations. Attempting unipolar operation would result in incorrect current paths and potential device damage due to improper biasing of internal transistors.

What is the purpose of the OSCM pin on the TB62261FTAG, and how is it configured?

OSCM pin sets the internal oscillator frequency that determines chopper timing. It is configured with an external resistor (e.g., 3.6 kΩ) and capacitor (e.g., 270 pF) to ground, yielding fOSCM ≈ 1.6 MHz and fchop ≈ 100 kHz. This tuning allows designers to optimize trade-offs: higher frequencies reduce current ripple but increase switching losses; lower frequencies improve thermal efficiency at the cost of increased ripple amplitude.

Does the TB62261FTAG require external flyback diodes for back-EMF protection?

No, the TB62261FTAG integrates body diodes within its MOSFET H-bridge outputs, eliminating need for external flyback diodes. However, system-level back-EMF management remains critical: the power supply must provide adequate sink capability during motor deceleration, and PCB layout must minimize inductance in VM/GND paths to prevent voltage overshoot beyond the 40 V absolute maximum rating.