Diodes Incorporated ZR285N802TA

Overview

ZR285N802TA from Zetex Semiconductors (now Diodes Incorporated) is a precision 2.5 V bandgap voltage reference IC in SO8 package, rated for ±2% initial tolerance, 30 ppm/°C typical temperature coefficient, and stable operation from 20 µA to 20 mA. It requires no external capacitor, achieves microsecond-scale settling, and supports industrial temperature range (−40°C to +85°C), making it suitable for battery-powered data acquisition front-ends.

For engineers reviewing the ZR285N802TA datasheet, ZR285N802TA pinout, ZR285N802TA application, or ZR285N802TA equivalent, key selection criteria include low knee current (15 µA typ), slope resistance (0.4 Ω typ), wide operating current range, capacitive load stability, and SO8 thermal/power dissipation capability (625 mW at 25°C).

Technical Context

The ZR285N802TA implements a two-terminal shunt reference topology with internal bandgap core, delivering fixed 2.5 V reverse breakdown voltage across −40°C to +85°C. Its low dynamic impedance (0.3–0.8 Ω at 100 Hz) and flat slope resistance vs. frequency up to 100 kHz ensure minimal AC error in precision ADC biasing and DAC reference paths.

Designed for high transient immunity, it withstands surge currents up to 200 mA and operates reliably without external stabilization-enabling direct use in low-noise, space-constrained analog signal chains where layout simplicity and power budget control are critical.

Key Specifications

Pinout & Package

SO8 package (suffix "N8"), 8-pin small outline integrated circuit with standard dual-in-line pinout. Pin 1 is floating or connected to pin 2 per datasheet; device functions as a two-terminal shunt reference - anode and cathode only - with remaining pins unused or internally tied.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar shunt voltage reference applications.

Compared with TL431ACDR and REF3025AIDBVR, the ZR285N802TA uniquely combines fixed 2.5 V output, sub-20 µA knee current, SO8 thermal robustness, and capacitor-free stability-making it optimal for space- and power-constrained shunt reference roles where supply headroom is limited and layout simplicity is mandatory.

Availability

ZR285N802TA is available at Aetrix Electronics and suitable for battery-powered data loggers, portable test equipment, and industrial analog input modules requiring stable component supply, long-term calibration integrity, and consistent SO8 package sourcing.

Supply support for ZR285N802TA 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

Zetex Semiconductors, acquired by Diodes Incorporated in 2008, specialized in high-performance analog and discrete semiconductors for industrial, automotive, and portable electronics.

The ZR285 series was developed specifically for precision shunt reference applications demanding micropower operation, low thermal drift, and ruggedness in harsh or space-limited environments.

FAQ

Is ZR285N802TA a two-terminal or three-terminal device?

ZR285N802TA is a two-terminal shunt voltage reference: anode and cathode only. Though packaged in an SO8, pins 3–7 are internally unconnected or tied; only pins 1/2 (anode) and pin 8 (cathode) are functional. This matches its schematic symbol and absolute maximum ratings table.

Can ZR285N802TA drive a 10 nF capacitive load directly?

Yes - the ZR285N802TA is explicitly characterized as stable with capacitive loads and requires no external compensation. Typical application curves show clean transient response even with 10 nF, supporting direct use with ADC sample-and-hold inputs or op-amp buffers without added series resistance.

What is the maximum safe reverse current before damage occurs?

The absolute maximum reverse current is 30 mA per datasheet. However, the device is ruggedized to survive transient surges up to 200 mA (non-repetitive), and is rated for continuous operation up to 20 mA. Sustained operation above 30 mA risks permanent parametric shift or thermal failure.

Does ZR285N802TA require a heatsink in SO8 package at 15 mA load?

No - at 15 mA and 2.5 V output, power dissipation is 37.5 mW, well below the SO8's 625 mW rating at 25°C. Even at 85°C ambient, junction temperature remains within limits without heatsinking, assuming standard 2 oz copper PCB layout with moderate thermal relief.