Diodes Incorporated ZXTR2005K-13

Overview

ZXTR2005K from Diodes Incorporated is a monolithic high-voltage linear regulator transistor integrating a Zener diode, emitter-follower transistor, and 150kΩ current-limiting resistor in a single TO252 (DPAK) package. It delivers a nominal 5V ±10% regulated output at up to 50mA continuous load with input voltage range of 10–100V, designed specifically for startup supply regulation in PoE-powered DC-DC converters.

For engineers reviewing the ZXTR2005K datasheet, ZXTR2005K pinout, ZXTR2005K application, or ZXTR2005K equivalent, key selection criteria include its 100V absolute maximum input rating, integrated 150kΩ bias resistor, 4.5–5.5V output tolerance at 15mA, junction-to-lead thermal resistance of 8.4°C/W, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

The ZXTR2005K implements a series linear regulator topology using an emitter-follower configuration, where the integrated Zener sets the base reference and the transistor provides low-dropout pass capability. Regulation is achieved without external feedback components due to monolithic integration of all biasing elements.

It operates as a fixed-output, high-input-voltage regulator with no enable or shutdown control-output remains active whenever VIN ≥ 10V and sufficient load (>10µA) is present. Thermal performance is defined by RθJL = 8.4°C/W when mounted on 50mm × 50mm 1oz copper, enabling 2.3W power dissipation at TA = 25°C.

Key Specifications

Pinout & Package

Package: TO252 (DPAK), surface-mount, with exposed VIN pad for thermal conduction and mechanical anchoring. Molded green compound, matte tin-plated leads, RoHS and halogen-free compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage linear regulator applications.

Compared with ALD110800S and LT3080MP, the ZXTR2005K uniquely combines 100V input capability, monolithic integration, AEC-Q101 qualification, and TO252 thermal performance-making it the only drop-in solution for space-constrained, high-reliability PoE and telecom startup supplies.

Availability

ZXTR2005K-13 is available at Aetrix Electronics and suitable for Power over Ethernet (PoE) interface design, telecom line card biasing, and industrial sensor transmitter supply requiring stable component supply across extended temperature and voltage ranges.

Supply support for ZXTR2005K-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability, application-optimized components for automotive, industrial, and communications markets.

The ZXTR series targets high-voltage linear regulation applications where traditional IC regulators fail-designed specifically to simplify auxiliary supply design in PoE, telecom, and industrial systems with minimal external components.

FAQ

What is the minimum load current required for regulation?

The ZXTR2005K requires a minimum load of 10µA on VOUT to maintain regulation. Below this threshold, output voltage may rise above 5.5V due to insufficient current through the internal Zener reference. This is critical in low-power sleep modes-designers should ensure either a permanent bleeder resistor or active load engagement.

Can ZXTR2005K operate with negative input voltage?

No. The absolute maximum rating specifies VIN ≥ –0.3V relative to GND. Applying negative voltage risks reverse-biasing internal junctions and damaging the monolithic structure. It is not rated for dual-supply or bipolar rail applications-only unidirectional 0–100V input operation is supported.

How does thermal performance change with smaller PCB copper areas?

When mounted on 15mm × 15mm 1oz copper instead of 50mm × 50mm, RθJA increases from 44°C/W to 90°C/W. This reduces maximum continuous power dissipation from 2.3W to 1.1W at TA = 25°C, limiting usable output current at high VIN-derating curves in DS36328 Rev. 3–2 must be consulted for safe operating area validation.

Is the ZXTR2005K pin-compatible with other TO252 regulators?

No. While the TO252 package has standard mechanical dimensions, the ZXTR2005K's pin assignment (VIN–GND–VOUT) differs from conventional three-terminal regulators like LM7805 (IN–GND–OUT). Substituting without verifying pin mapping risks catastrophic short-circuit or reverse bias damage to the device or downstream circuitry.