Microchip Technology 1N4751CP/TR12

Overview

1N4751CP/TR12 from Microsemi is a 1.0 W axial-lead silicon Zener diode with nominal zener voltage of 30 V, ±5% tolerance (A suffix), plastic DO-41 package, and rated for operation from –65 °C to +150 °C. It regulates voltage in power supply reference, overvoltage protection, and voltage-clamping circuits where stable 30 V breakdown under reverse bias is required.

For engineers reviewing the 1N4751CP/TR12 datasheet, 1N4751CP/TR12 pinout, 1N4751CP/TR12 application, or 1N4751CP/TR12 equivalent, key selection criteria include zener voltage accuracy, dynamic impedance at test current, surge current rating, thermal resistance, and RoHS-compliant tape-and-reel packaging (TR12).

Technical Context

The 1N4751CP/TR12 operates as a reverse-biased voltage reference device, maintaining a stable 30 V across its terminals when reverse current exceeds the knee region (IZK = 0.25 mA). Its regulation performance is defined by low dynamic impedance (ZZT = 40 Ω at IZT = 8.5 mA) and tight thermal coefficient behavior above 6 V.

Designed for through-hole mounting, it features tin-lead or RoHS-compliant matte-tin plating, UL94V-0 epoxy body, cathode band polarity marking, and JEDEC-standard DO-41 mechanical dimensions. It delivers 1.0 W steady-state dissipation at TL < 105 °C (3/8″ lead length) or TA < 45 °C on FR4 board.

Key Specifications

Pinout & Package

DO-41 (JEDEC DO-204AL) plastic axial-lead package with cathode indicated by color band; leads are tin-lead or RoHS-compliant matte-tin plated, void-free UL94V-0 epoxy body, weight 0.7 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4751A and MMSZ5256ET1G, the 1N4751CP/TR12 uniquely combines JEDEC-standard axial form factor, full 1 W power rating, EIA-296 tape-and-reel delivery, and verified low-impedance regulation - making it optimal for industrial power supplies requiring manual or automated through-hole assembly with long-term thermal reliability.

Availability

1N4751CP/TR12 is available at Aetrix Electronics and suitable for industrial power supplies, overvoltage protection circuits, and voltage reference designs requiring stable component supply with RoHS-compliant packaging and automated assembly support.

Supply support for 1N4751CP/TR12 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, RF, and discrete components for aerospace, defense, and industrial markets.

The 1N47xxAP series was developed to deliver JEDEC-standard, high-stability Zener regulation in ruggedized plastic packages for mission-critical power conditioning and protection functions.

FAQ

What is the zener voltage tolerance of the 1N4751CP/TR12?

The 1N4751CP/TR12 has a nominal zener voltage of 30 V with ±5% tolerance, as indicated by the "A" suffix in the part number per Microsemi's JEDEC-registered specification. This tolerance is measured at 25 °C lead temperature with 90 seconds of dc current application and applies across the full operating temperature range of –65 °C to +150 °C. The 1N4751CP/TR12 does not offer tighter tolerances such as ±1% or ±2% - those require suffixes D or C, respectively, which are not present in this variant.

Does the 1N4751CP/TR12 support automated assembly?

Yes, the 1N4751CP/TR12 is supplied in EIA-296 standard tape-and-reel packaging (denoted by "TR12" in the part number), enabling compatibility with pick-and-place equipment for high-volume through-hole assembly. Its DO-41 axial-lead configuration is supported by industry-standard axial feeders, and the RoHS-compliant matte-tin plating ensures reliable solder wetting during wave or selective solder processes. No additional packaging conversion is required to deploy the 1N4751CP/TR12 in automated production lines.

What is the maximum surge current rating for the 1N4751CP/TR12?

Per Microsemi's datasheet, the 1N4751CP/TR12 has a maximum surge current (I_SM) rating of 1000 mA, measured using a ½-sine wave pulse of 1/120 second duration at 25 °C ambient. This rating reflects short-duration transient energy absorption capability during overvoltage events. Engineers must ensure that average power dissipation remains within the 1.0 W steady-state limit and that thermal derating curves (Figure 1) are applied for sustained operation above 45 °C ambient or 105 °C lead temperature.

How does the thermal resistance of the 1N4751CP/TR12 affect PCB layout?

The 1N4751CP/TR12 specifies 45 °C/W junction-to-lead thermal resistance at 3/8″ (10 mm) lead length from the body - meaning PCB layout should maintain ≥10 mm straight lead length between the DO-41 body and solder joint to achieve rated 1.0 W dissipation. When mounted on FR4 with 1 oz copper, its junction-to-ambient resistance rises to 105 °C/W, so thermal pads or copper pours are recommended if ambient exceeds 45 °C. Layouts omitting lead-length margin will require power derating per Figure 1 in the datasheet.

Is the 1N4751CP/TR12 RoHS compliant?

Yes, the 1N4751CP/TR12 is RoHS compliant, as confirmed by the "e3" designation in Microsemi's official documentation and product family labeling. Its terminations use annealed matte-tin plating per MIL-STD-750 Method 2026, and the void-free thermosetting epoxy case meets UL94V-0 flammability requirements. The "e3" suffix explicitly denotes RoHS compliance, and no lead (Pb) is present in the finish or package materials - consistent with EU Directive 2011/65/EU Annex II maximum concentration values.