Microchip Technology MS1N8170US/TR

Overview

MS1N8170US/TR from Microsemi is a voidless-hermetically-sealed unidirectional transient voltage suppressor (TVS) designed for high-reliability, high-frequency signal line protection. It delivers 150 W peak pulse power at 10/1000 µs, features 4 pF capacitance, and has a 53.0 V working standoff voltage (VWM) with 77.0 V clamping voltage (VC) at 11.7 A peak surge current - ideal for ESD/EFT protection in aerospace and telecom front-end interfaces.

For engineers reviewing the MS1N8170US/TR datasheet, MS1N8170US/TR pinout, MS1N8170US/TR application, or MS1N8170US/TR equivalent, key selection criteria include low-capacitance transient suppression, Category 1 metallurgical bond reliability, hermetic glass packaging, and compliance with IEC61000-4-2/4-4/4-5 standards for mission-critical systems.

Technical Context

This TVS employs a unique series-connected rectifier diode in anti-parallel configuration with the avalanche junction to achieve ultra-low 4 pF capacitance while maintaining unidirectional operation. Its hard-glass hermetic construction uses internal tungsten slugs and Category 1 metallurgical bonds for radiation hardness and thermal stability across –55 °C to +175 °C.

The device operates with 53.0 V working standoff voltage and clamps to 77.0 V at 11.7 A (10/1000 µs), delivering robust secondary lightning protection per IEC61000-4-5 Level 3. It exhibits 0.104 %/°C breakdown voltage temperature coefficient and <0.5 µA standby leakage at rated VWM.

Key Specifications

Pinout & Package

MS1N8170US/TR is housed in an axial-leaded, voidless-hermetically-sealed hard-glass package with cathode band marking. Leads are tin/lead or RoHS-compliant matte tin-plated copper. Dimensions: BD = 0.060–0.085 in (1.52–2.16 mm), BL = 0.106–0.175 in (2.69–4.45 mm), LL = 0.800–1.300 in (20.32–33.02 mm).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with SMCJ53A and 1N8170US, MS1N8170US/TR uniquely combines hermetic glass construction, Category 1 bonding, and 4 pF capacitance - making it the only option qualified for radiation-hardened, high-frequency, zero-failure-tolerance systems where long-term parameter stability is mandatory.

Availability

MS1N8170US/TR is available at Aetrix Electronics and suitable for RF front-end protection, aerospace avionics data buses, and industrial Ethernet PHY interfaces requiring stable component supply, long-lifecycle assurance, and guaranteed hermetic reliability.

Supply support for MS1N8170US/TR 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

Microsemi Corporation (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal ICs, RF solutions, and radiation-hardened components for defense, aerospace, and industrial markets.

The 1N8149–1N8182 family was engineered specifically for ultra-low-capacitance transient suppression in mission-critical RF and data interfaces where conventional TVS devices introduce unacceptable signal distortion or reliability risk.

FAQ

What is the clamping voltage of MS1N8170US/TR at its rated peak surge current?

The MS1N8170US/TR clamps to 77.0 V at 11.7 A peak impulse current (10/1000 µs waveform). This value is measured per standard test conditions in the Microsemi T4-LDS-xxxx datasheet and defines the maximum overvoltage imposed on protected circuitry during a full-rated transient event. The clamping performance remains stable across its full operating temperature range due to its hermetic construction and Category 1 metallurgical bond.

Is MS1N8170US/TR suitable for bidirectional transient protection?

MS1N8170US/TR is inherently unidirectional. For bidirectional protection, two MS1N8170US/TR devices must be connected in anti-parallel configuration - as documented in Figure 5 of the official datasheet. This arrangement doubles the effective capacitance to 8 pF but retains the same clamping performance in both polarities, enabling use on AC-coupled or floating signal lines such as Ethernet PHY interfaces.

Does MS1N8170US/TR meet space-level reliability standards?

Yes. MS1N8170US/TR incorporates Category 1 internal metallurgical bonds and voidless hermetic glass packaging, satisfying MIL-STD-750 Method 1020 for ESD insensitivity and Microsemi MicroNote 050 for inherent radiation hardness. These features make MS1N8170US/TR suitable for low-earth orbit (LEO) satellite payloads and avionics systems requiring TID tolerance and single-event latch-up immunity without derating.

What is the thermal resistance and steady-state power limit of MS1N8170US/TR?

MS1N8170US/TR has a junction-to-ambient thermal resistance (RθJA) of 150 °C/W and a maximum steady-state average power dissipation (PM(AV)) of 1.0 W at TA = 25 °C. This rating assumes adequate PCB copper area and thermal vias; exceeding 1.0 W continuously risks junction temperature exceedance beyond the +175 °C absolute maximum, especially in enclosed or high-ambient environments.

How does the 4 pF capacitance of MS1N8170US/TR compare to standard TVS diodes?

The 4 pF capacitance of MS1N8170US/TR is among the lowest available for a 150 W-rated TVS - achieved via a proprietary series-connected rectifier diode architecture. Standard SMC-packaged TVS devices (e.g., SMCJ53A) typically measure 4.5–12 pF. This 1–2 pF reduction enables MS1N8170US/TR to protect >3 GHz RF paths without degrading return loss or group delay, a critical advantage in 5G and satcom front ends where conventional TVS devices would require complex compensation networks.