Diodes Incorporated ZXTR2012FF-7

Overview

ZXTR2012FF from Diodes Incorporated is a monolithic high-voltage linear regulator transistor in SOT23F, integrating an NPN transistor, Zener diode, and bias resistor to deliver 12V ±10% output at up to 30mA from 15–100V input. It functions as an emitter-follower series regulator for PoE-powered devices, networking infrastructure, and telecom power rails where standard LDOs fail due to input voltage limits.

For engineers reviewing the ZXTR2012FF datasheet, ZXTR2012FF pinout, ZXTR2012FF application, or ZXTR2012FF equivalent, key selection criteria include its 100V absolute max input rating, 12V regulated output with ±10% tolerance, 36mA continuous output current at 48V input, thermal resistance of 95°C/W (25mm² copper), and SOT23F package compatibility with space-constrained PoE endpoints.

Technical Context

The ZXTR2012FF implements a fixed-output, series linear regulation architecture using an internal emitter-follower stage with integrated Zener reference and base-bias resistor. Its regulation relies on external capacitor stabilization (10µF recommended at VOUT) and requires ≥10µA minimum load to maintain regulation.

It operates across -65°C to +150°C junction temperature, supports transient pulses up to 880mA (100µs) at VIN = 48V, and exhibits 8.0mV/°C output voltage temperature coefficient. Line regulation is specified at 240–750mV over 15–72V input range, and load regulation spans -450 to -750mV from 0.1mA to 100mA output.

Key Specifications

Pinout & Package

Package: SOT23F - 3-pin surface-mount plastic package with exposed VIN pad for enhanced thermal conduction; dimensions 2.90 × 2.40 × 0.90 mm (L × W × H); RoHS-compliant matte tin-plated leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTR2012FF, ZXTR2008F offers lower output voltage and slightly better efficiency at light loads, while LT3080MPMS8E provides wide adjustability and higher current but demands more board space and design effort-making ZXTR2012FF optimal for cost-sensitive, space-constrained 12V PoE and telecom applications.

Availability

ZXTR2012FF is available at Aetrix Electronics and suitable for Power over Ethernet (PoE) powered devices, telecom line card bias supplies, and industrial remote sensor node power requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for ZXTR2012FF 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 needs in infrastructure equipment, with design focus on simplifying power architecture in PoE, telecom, and industrial control systems through monolithic integration and robust thermal performance.

FAQ

What is the minimum load required for ZXTR2012FF to maintain regulation?

The ZXTR2012FF requires a minimum load of 10µA drawn from the VOUT pin to sustain proper regulation. This is due to the internal Zener reference and bias network design; operation below this threshold may cause output voltage drift or instability. A 100kΩ pull-down resistor to GND satisfies this requirement in no-load or ultra-low-power states.

Can ZXTR2012FF be used with input voltages below 15V?

No-ZXTR2012FF is not guaranteed to regulate below 15V input. Its internal Zener reference and transistor biasing require ≥15V to establish stable base-emitter drive and maintain 12V output within specification. At 13V input, output drops to ~10.8V and regulation degrades significantly; use only within the 15–100V specified range.

Is an input capacitor required for stable operation?

Yes-a 1µF ceramic capacitor between VIN and GND is recommended per the datasheet to suppress high-frequency noise and prevent oscillation caused by source impedance. This capacitor should be placed within 5mm of the VIN and GND pins; absence may result in audible ringing or output voltage overshoot during load transients.

How does thermal performance change when mounted on 15mm² versus 25mm² copper?

Thermal resistance increases from 95°C/W (25mm² copper) to 126°C/W (15mm² copper), reducing maximum continuous power dissipation from 1.3W to 0.95W at TA = 25°C. For a 48V input delivering 30mA (1.44W dissipated), the smaller pad would exceed safe junction temperature-thus 25mm² minimum copper is mandatory for full-rated operation.