STMicroelectronics TD351IN

Overview

TD351IN from STMicroelectronics is an advanced high-side IGBT and power MOSFET gate driver in SO-8 package, featuring 1.7 A sink / 1.3 A source peak output current, active Miller clamp, two-level turn-off with adjustable delay, UVLO protection, and 2 kV HBM ESD rating. It enables robust 1200 V three-phase inverter designs using bootstrap supply without negative rail.

For engineers reviewing the TD351IN datasheet, TD351IN pinout, TD351IN application, or TD351IN equivalent, this page delivers verified functional architecture, timing-critical design values (e.g., 100 ns rise/fall, 100–220 ns min input pulse), and real-world implementation guidance for motor control and UPS systems.

Technical Context

The TD351IN integrates a dedicated Miller clamp circuit that activates when gate voltage falls below 2.0 V (relative to VL), clamping at ≤ VL + 4 V for up to 500 mA Miller current-eliminating need for negative gate drive. Its two-level turn-off uses external Rd/Cd network to set programmable delay (Ta ≈ 0.7 × Rd × Cd) and adjustable off-level via LVOFF pin.

Input stage accepts optocoupler or pulse transformer signals with edge-triggered, active-low logic; internal 5.0 V reference (±1.5% over temp) supports precise timing generation. UVLO thresholds are 9–12 V with 1 V hysteresis, and output stage maintains ≥1.0 A sink / ≥0.75 A source across –40°C to +125°C.

Key Specifications

Pinout & Package

TD351IN is housed in a standard SO-8 surface-mount package (ECOPACK® compliant), with 1.27 mm pitch, 5.0 mm × 4.0 mm body, and thermal resistance R_thJA = 150 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar IGBT gate driver applications.

Compared with IR2110PbF and UCC27531DR, TD351IN uniquely combines Miller clamping, two-level turn-off, and bootstrap-compatible operation-making it the only option among the three qualified for ruggedized 1200 V inverter designs without auxiliary negative supplies.

Availability

TD351IN is available at Aetrix Electronics and suitable for industrial motor drives, uninterruptible power supplies, renewable energy inverters, and electric vehicle onboard chargers requiring stable component supply and long-term lifecycle support.

Supply support for TD351IN 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power ICs, sensors, and analog devices for industrial, automotive, and consumer markets.

TD351IN belongs to ST's high-voltage gate driver product line, engineered specifically for reliable, high-efficiency IGBT control in 1200 V industrial power conversion systems with emphasis on fault resilience and supply simplicity.

FAQ

What is the recommended external timing capacitor (Cd) value for 2 µs two-level turn-off delay?

For a 2 µs turn-off delay (Ta), use Cd = 2000 ns / (0.7 × Rd). With Rd = 10 kΩ, Cd = 286 pF-standard value 270 pF or 330 pF is acceptable. ST recommends Cd between 100 pF and 2.2 nF; values outside this range degrade timing accuracy and noise immunity.

Can TD351IN drive SiC MOSFETs effectively?

TD351IN can drive 1200 V SiC MOSFETs in limited cases, but its 100 ns rise/fall time and 1.7 A sink current are suboptimal for SiC's fast switching demands. It lacks dedicated SiC features like desaturation detection or active miller clamping tuned for SiC's lower Q_gd; ST recommends the STGAP2SIC series for SiC-specific designs.

How does the active Miller clamp interact with the output stage during normal switching?

The Miller clamp (CLAMP pin) activates only when the gate voltage drops below 2.0 V relative to VL and remains active until the next rising edge on IN. It does not interfere with turn-on or steady-state conduction-it only engages during the OFF interval to shunt Miller current away from the gate driver output stage.

Is TD351IN pin-compatible with newer ST gate drivers like the STGAP2SIC?

No-TD351IN uses an SO-8 footprint with unique pin functions (e.g., VREF, CD, LVOFF, CLAMP), while STGAP2SIC employs SO-8 or DSO-8 packages with different pinouts (e.g., DESAT, FLT, VCC, HO). Direct replacement requires PCB redesign and firmware adaptation for new feature sets.