Diodes Incorporated ZSR330N8TA

Overview

ZSR330N8TA from Zetex plc is a fixed-output 3.3 V positive voltage regulator in SO8 package, delivering up to 200 mA output current with ±2.5% initial output voltage tolerance (3.218–3.382 V), 350 µA typical quiescent current, and internal thermal shutdown and short-circuit protection. It operates across –55°C to +125°C and requires no external components for stability-used in local regulation for microcontroller power rails, sensor interfaces, and industrial control modules.

For engineers reviewing the ZSR330N8TA datasheet, ZSR330N8TA pinout, ZSR330N8TA application, or ZSR330N8TA equivalent, key selection criteria include dropout behavior at 5.3 V minimum input, 50 µV_rms output noise (10 Hz–10 kHz), 64 dB ripple rejection at 120 Hz, and SO8 thermal performance (780 mW @ 25°C).

Technical Context

The ZSR330N8TA employs a monolithic bipolar linear regulator architecture with internal current limiting and thermal foldback. Its output voltage is trimmed during production to maintain 3.3 V ±2.5% over load (1–200 mA), line (5.3–20 V), and temperature (–55°C to +125°C) variations.

It achieves stable regulation without external capacitors due to integrated compensation and exhibits low temperature coefficient (0.1 mV/°C) and minimal load/line regulation (7.5 mV line, 5 mV load). Input transient response is characterized by <50 µs recovery from ±0.2 V output deviation under 5 V/µs dV_in/dt.

Key Specifications

Pinout & Package

SO8 package (suffix N8), surface-mount, 8-pin plastic DIP outline with exposed thermal pad (pin 4 internally connected to GND or electrically isolated per layout). Pin 1 = Input, Pin 2 = Ground, Pin 3 = Output, Pin 4 = GND (thermal pad), Pins 5–8 = NC or unused.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output linear regulator applications.

Compared with TLV73333PDBVR and MCP1703T-3302E/MB, the ZSR330N8TA offers superior thermal robustness (–55°C to +125°C full-spec), higher PSRR (64 dB), and proven reliability in high-temperature industrial deployments-but requires larger SO8 footprint and higher minimum input voltage.

Availability

ZSR330N8TA is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and medical sensor signal conditioning requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for ZSR330N8TA 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 plc (now part of Diodes Incorporated) is a UK-based semiconductor company specializing in high-performance analog and discrete devices for industrial, automotive, and power management applications.

The ZSR Series was designed specifically for rugged local voltage regulation-emphasizing fault resilience, wide temperature operation, and zero-external-component simplicity in space-constrained embedded systems.

FAQ

What is the minimum input voltage required for regulation at full load?

The ZSR330N8TA requires a minimum input voltage of 5.3 V to maintain 3.3 V output at 200 mA load, per datasheet test conditions. Below this, output voltage drops linearly with input; the 5.0 V typical value applies only at lighter loads (≤100 mA). This 2.0 V headroom requirement reflects its bipolar process dropout characteristics.

Can the ZSR330N8TA be used without input or output capacitors?

Yes-the ZSR330N8TA is internally compensated and stable with no external capacitors. However, a 1 µF minimum ceramic capacitor on the input is recommended to limit voltage overshoot during thermal shutdown events, especially when driven from inductive sources. No output capacitor is required for stability.

How does thermal performance differ between SO8 and SOT-223 packages?

The SO8 package (ZSR330N8TA) has a rated power dissipation of 780 mW at 25°C ambient, derated linearly to zero at 125°C. The SOT-223 variant (ZSR330G) supports 2 W under identical PCB conditions (2-inch² copper), offering ~2.6× higher thermal capacity-critical for continuous 200 mA operation in enclosed enclosures.

Is the ZSR330N8TA RoHS compliant and lead-free?

Yes-Zetex issued RoHS-compliant versions of the ZSR Series prior to Diodes Incorporated's acquisition. The ZSR330N8TA carries lead-free finish and meets EU RoHS Directive 2011/65/EU requirements, with full material declarations available upon request through Aetrix Electronics' compliance portal.