Microchip Technology 1N5370CE3/TR13

Overview

1N5370CE3/TR13 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 56 V, ±2% tolerance (C suffix), 20 mA test current, 35 Ω dynamic impedance at I_ZT, and maximum reverse current of 0.5 µA at 42.6 V. It operates from –65 °C to +150 °C and is used for precision voltage reference and overvoltage protection in industrial power supplies.

For engineers reviewing the 1N5370CE3/TR13 datasheet, 1N5370CE3/TR13 pinout, 1N5370CE3/TR13 application, or 1N5370CE3/TR13 equivalent, key selection criteria include Zener voltage tolerance, thermal resistance (25 °C/W junction-to-lead), surge current rating (280 A), voltage regulation (ΔV_Z = 1.00 V), and RoHS-compliant matte-tin plating per MIL-STD-750.

Technical Context

This device functions as a two-terminal voltage regulator operating in reverse-biased breakdown mode. Its 56 V nominal Zener voltage is specified at 20 mA test current with ±2% tolerance, and it maintains stable regulation across 10–50% of I_ZM (max 280 mA) with ΔV_Z ≤ 1.00 V.

Thermal design relies on low junction-to-lead thermal resistance (25 °C/W at 10 mm lead length), enabling 5 W dissipation at T_L = 25 °C. Reverse leakage is tightly controlled: ≤0.5 µA at 42.6 V (95% of V_Z), supporting high-impedance bias networks.

Key Specifications

Pinout & Package

Package: Axial-leaded T-18 plastic case (void-free UL94V-0 epoxy), cathode indicated by band; leads plated with RoHS-compliant annealed matte tin per MIL-STD-750 Method 2026.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener voltage regulation applications.

Compared with 1N5370B and MMSZ5255B-TP, the 1N5370CE3/TR13 delivers superior thermal performance (5 W vs. 0.5 W), tighter voltage control (±2% vs. ±5%), and proven surge resilience (280 A), making it the sole option for high-reliability, high-power Zener regulation in harsh environments.

Availability

1N5370CE3/TR13 is available at Aetrix Electronics and suitable for industrial power supplies, automotive load-dump protection circuits, programmable voltage monitors, and high-voltage bias networks requiring stable component supply and long-term lifecycle support.

Supply support for 1N5370CE3/TR13 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 (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal components for aerospace, defense, and industrial markets.

The 1N53xxB series was engineered for ruggedized voltage regulation in mission-critical power systems, emphasizing thermal robustness, surge immunity, and extended temperature operation without derating.

FAQ

What is the Zener voltage tolerance of the 1N5370CE3/TR13?

The 1N5370CE3/TR13 has a Zener voltage tolerance of ±2%, denoted by the "C" suffix in its part number. This means its measured V_Z falls within 54.88 V to 57.12 V at 20 mA test current and 25 °C lead temperature. This tighter tolerance supports precision reference applications where post-calibration is impractical, such as in sealed industrial controllers or automotive ECUs.

Does the 1N5370CE3/TR13 require dry packing before reflow soldering?

No, the 1N5370CE3/TR13 does not require dry packing. Its moisture sensitivity level is IPC/JEDEC J-STD-020B Level 1, meaning it can be stored indefinitely at ambient conditions (<30 °C/60% RH) without baking prior to reflow. This simplifies manufacturing logistics and eliminates risk of popcorning during standard Pb-free reflow profiles up to 260 °C for 10 seconds.

What is the maximum steady-state power dissipation of the 1N5370CE3/TR13 on a standard FR4 PCB?

When mounted on a standard FR4 PCB (1 oz Cu, 4 mm² copper pads, 1 mm track width, 25 mm length), the 1N5370CE3/TR13 has a steady-state power rating of 1.47 W at 25 °C ambient temperature. This value derives from its 85 °C/W junction-to-ambient thermal resistance under those specific board conditions, as documented in Microsemi's datasheet Figure 1 derating curve.

Can the 1N5370CE3/TR13 be used as a direct replacement for the 1N5370B in existing designs?

Yes, the 1N5370CE3/TR13 is mechanically and electrically compatible with the 1N5370B, sharing identical T-18 package, pinout, thermal characteristics, and absolute maximum ratings. The primary difference is tighter ±2% voltage tolerance versus ±5%, which improves regulation accuracy without requiring layout or thermal changes-making it a drop-in upgrade for enhanced performance.

What is the surge current rating of the 1N5370CE3/TR13 and how is it defined?

The 1N5370CE3/TR13 has a peak non-repetitive surge current rating of 280 A, defined per JEDEC standard as the maximum amplitude of a single 8.3 ms half-sine waveform. This rating reflects its ability to absorb transient energy during events like inductive switch-off or load dump, and is validated under conditions where junction temperature remains below 150 °C during the pulse.