STMicroelectronics TN805-600B

Overview

TN805-600B from STMicroelectronics is a standard-sensitivity 8 A, 600 V silicon-controlled rectifier (SCR) in DPAK package, with gate trigger current IGT of 0.5–5 mA (max), on-state rms current IT(RMS) = 8 A at TC = 110 °C, and critical dV/dt immunity ≥50 V/µs at Tj = 125 °C. It serves as a main switching element in overvoltage crowbar protection circuits for DC power supplies and motor control circuits in portable power tools.

For engineers reviewing the TN805-600B datasheet, TN805-600B pinout, TN805-600B application, or TN805-600B equivalent, this part supports robust phase-angle control, high-noise immunity triggering, and thermal-stable conduction in compact surface-mount designs requiring ≤8 A RMS switching at ≤600 V blocking voltage.

Technical Context

This SCR operates in forward-blocking mode until gate-triggered into conduction, sustaining up to 600 V repetitive peak off-state voltage (VDRM/VRRM) and holding current IH ≤25 mA at Tj = 25 °C. Its dynamic resistance Rd ≤46 mΩ and threshold voltage Vt0 ≤0.85 V at Tj = 125 °C ensure low conduction loss during sustained on-state operation.

The device features a minimum dV/dt immunity of 50 V/µs with gate open at Tj = 125 °C, enabling reliable operation in noisy AC line environments. Thermal resistance Rth(j-c) = 1.3 °C/W (DPAK) allows efficient heat transfer to PCB copper when mounted per recommended footprint (6.7 × 3.0 mm pad).

Key Specifications

Pinout & Package

DPAK (TO-252) package: surface-mount, 3-terminal, single-die SCR with exposed cathode tab for thermal and electrical connection. Dimensions: 6.22 mm × 6.73 mm × 2.40 mm (L × W × H); recommended copper pad: 6.7 mm × 3.0 mm under tab.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SCR switching applications.

Compared with TN805-600B, TN815-600B offers superior noise immunity at the cost of higher gate drive demand, while TS820-600B reduces gate drive burden but sacrifices ruggedness in noisy line applications-making TN805-600B the balanced choice for general-purpose 8 A, 600 V switching.

Availability

TN805-600B is available at Aetrix Electronics and suitable for overvoltage crowbar protection, power tool motor control, and inrush current limiting applications requiring stable component supply across production lifecycles.

Supply support for TN805-600B 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 analog, power, MCU, and sensor solutions for industrial, automotive, and consumer markets.

TN805 belongs to ST's standard-sensitivity 8 A SCR product line, engineered for cost-effective, thermally efficient AC/DC power control in space-constrained surface-mount applications.

FAQ

What is the maximum junction temperature for continuous operation of TN805-600B?

The specified operating junction temperature range is –40 °C to +125 °C. Continuous operation must maintain Tj ≤125 °C, enforced by thermal design using the DPAK package's Rth(j-c) = 1.3 °C/W and recommended 6.7 mm × 3.0 mm copper pad area per DS2118 Figure 16.

Can TN805-600B replace TS820-600B in an existing design?

No direct replacement: TN805-600B requires up to 5 mA gate current versus TS820-600B's 0.2 mA maximum. Substituting without upgrading the gate driver risks unreliable turn-on. Also, TN805's dV/dt immunity (50 V/µs) is lower than TS820's (≥5 V/µs at sensitive level), increasing susceptibility to false triggering in low-noise circuits.

Is TN805-600B compliant with RoHS and halogen-free standards?

Yes. Per DS2118 Rev 9 Section 2.1, the DPAK package uses halogen-free molding compound meeting UL94 V0 and lead-free plating, fully compliant with RoHS Directive 2011/65/EU and ST's ECOPACK2 environmental standard.

What is the recommended gate resistor value for reliable triggering?

Based on IGT(max) = 5 mA and typical VGT(max) = 1.3 V, a 220 Ω gate resistor limits peak gate current to ~11 mA when driven from a 12 V source (per Table 3 test condition), ensuring safe triggering while providing noise filtering. Lower values (e.g., 100 Ω) may be used for faster turn-on in low-EMI environments.