Diodes Incorporated ZSR330GTA

Overview

ZSR330GTA from Zetex plc is a fixed-output 3.3 V positive voltage regulator in SOT223 package, designed for local regulation in space-constrained PCBs. It delivers up to 200 mA output current with ±2.5% initial output voltage tolerance (3.218–3.382 V), 350 µA typical quiescent current, and operates across –55°C to +125°C. It is used in microcontroller power rails, sensor interface supplies, and industrial control modules where thermal robustness and no-external-component stability are required.

For engineers reviewing the ZSR330GTA datasheet, ZSR330GTA pinout, ZSR330GTA application, or ZSR330GTA equivalent, key selection criteria include dropout behavior under load transients, ripple rejection at 120 Hz (50–64 dB), temperature coefficient (0.1 mV/°C), and thermal shutdown activation at junction temperatures exceeding design limits.

Technical Context

The ZSR330GTA employs an internal bandgap reference and error amplifier driving a pass transistor, with integrated thermal shutdown and short-circuit current limiting. Its architecture ensures stability without external capacitors, even under rapid line/load transients (e.g., dV_in/dt = 5 V/µs, dI_o/dt = 1 A/µs).

It achieves low output noise (50 µV_rms, 10 Hz–10 kHz) and high PSRR (64 dB typical at 120 Hz) due to high open-loop gain and optimized internal compensation. The device maintains regulation down to 5.3 V input (min 5.0 V), with dropout voltage rising to ~2.0 V at 125°C under full load.

Key Specifications

Pinout & Package

SOT223 package (suffix G): 4-pin thermally enhanced surface-mount outline with exposed thermal pad (pin 2). Pin 4 is internally connected to pin 2 or may be left floating per layout guidance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV73333PDBVR and MCP1700T-3302E/MB, the ZSR330GTA uniquely combines capacitor-free stability, –55°C to +125°C junction-rated operation, and integrated fault protection - making it the preferred choice for ruggedized embedded systems where reliability trumps minimal I_q.

Availability

ZSR330GTA is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and medical sensor hubs requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ZSR330GTA 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-reliability analog and power management ICs for industrial and automotive markets.

The ZSR Series was developed specifically for local voltage regulation in harsh-environment electronics, emphasizing thermal resilience, fault tolerance, and minimal external component count over raw efficiency.

FAQ

Does ZSR330GTA require an input or output capacitor for stability?

No. The ZSR330GTA is internally compensated and fully stable with zero external capacitors. However, a ≥1 µF ceramic input capacitor is recommended when powered from inductive sources to prevent input voltage overshoot during thermal shutdown events. An output capacitor is optional but improves transient response.

What is the maximum power dissipation of ZSR330GTA in SOT223 package?

At 25°C ambient, the SOT223 package supports 2 W maximum power dissipation, assuming mounting on a 2-inch square PCB. This derates linearly to zero at 125°C ambient. Actual usable power depends on PCB copper area, airflow, and thermal vias - typical continuous output at 200 mA requires ≤1.5 V dropout (e.g., Vin ≤ 4.8 V) at 25°C.

Can ZSR330GTA be used in automotive applications?

Yes. It is qualified for –55°C to +125°C junction operation, features internal thermal shutdown and short-circuit protection, and withstands input transients up to 20 V - meeting requirements for body electronics and infotainment power rails. It is not AEC-Q100 qualified, so system-level validation is required for safety-critical functions.

How does ZSR330GTA behave during thermal shutdown?

When junction temperature exceeds its design limit (typically ~165°C), the device ceases regulation and pulls output low. Upon cooling, it automatically recovers regulation without reset or external intervention. During shutdown, input-to-output leakage remains low (<1 µA), preventing unintended downstream power-up.