Diodes Incorporated ZRT050GC1TA

Overview

ZRT050GC1TA from Diodes Incorporated is a monolithic 4.9 V precision voltage reference IC with 1% initial tolerance, 150 μA knee current, and ±5% trim capability via external resistor. It delivers stable output at 500 μA load across –40°C to +85°C, features 1.25 Ω slope resistance, and operates without external stabilization capacitors in most applications - used in high-accuracy ADC/DAC biasing and sensor excitation circuits.

For engineers reviewing the ZRT050GC1TA datasheet, ZRT050GC1TA pinout, ZRT050GC1TA application, or ZRT050GC1TA equivalent, key selection criteria include its 50 µV_P-P (0.1–10 Hz) noise, 15–50 ppm/°C temperature coefficient, trim-adjustable output, SOT223 thermal performance, and absence of low-temperature derating requirements.

Technical Context

The ZRT050GC1TA implements a bandgap-based reference core with integrated trim node, enabling precise post-manufacture calibration. Its low 1.25 Ω slope resistance ensures minimal load regulation error, while the 150 μA knee current allows stable operation down to ultra-low quiescent current systems.

It achieves 5.4–17.2 mV total output variation over –40°C to +85°C and supports adjustable output via a single external resistor between TRIM and GND. The device's 50 µV_P-P low-frequency noise and no-external-capacitor design simplify layout in noise-sensitive analog signal chains.

Key Specifications

Pinout & Package

SOT223 surface-mount package with exposed thermal pad (pin 4 internally floating or tied to pin 2 for enhanced thermal conduction). Compact 6.3–6.7 mm × 3.3–3.7 mm footprint, 1.8 mm max height, optimized for automated assembly and thermal dissipation up to 2 W at 25°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF5045AIDR and ADR4540BRZ, the ZRT050GC1TA trades ultimate stability for on-board adjustability, smaller SOT223 footprint, and ultra-low knee current - making it optimal for cost-constrained, field-calibratable industrial sensors rather than lab-grade instruments.

Availability

ZRT050GC1TA is available at Aetrix Electronics and suitable for industrial sensor conditioning, high-resolution data acquisition, portable medical instrumentation, and PLC analog I/O requiring stable component supply with consistent parametric performance across production lots.

Supply support for ZRT050GC1TA 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 industrial, computing, and consumer markets.

The ZRT series targets precision analog subsystems requiring low-cost, trimmable references with robust thermal behavior - designed specifically for sensor excitation, data converter biasing, and closed-loop calibration in space- and power-constrained environments.

FAQ

Can the TRIM pin be left unconnected without affecting basic operation?

Yes. The TRIM pin is fully optional: leaving it open-circuit configures the device for nominal 4.9 V output with 1% initial tolerance. No pull-up, pull-down, or termination is required. Internal circuitry ensures stable regulation regardless of TRIM pin state, and the datasheet explicitly states "when the trim facility is not used, the pin should be left open circuit."

What is the maximum capacitive load the ZRT050GC1TA can drive without oscillation?

The ZRT050GC1TA is stable with capacitive loads up to 10 nF without external compensation, per Diodes' characterization in DS33259. For loads >10 nF (e.g., long traces or multiple bypass caps), a series resistor (1–10 Ω) between VR and the capacitor restores phase margin. No external capacitor is required for stability in typical applications.

Does the SOT223 thermal pad require electrical connection to ground?

No. Pin 4 is an exposed thermal pad with no internal electrical connection. It may be left floating or soldered to a PCB ground plane solely for thermal conduction. Diodes' package drawing confirms it is "not electrically connected," and tying it to GND is permissible only for thermal enhancement - not for functional grounding.

How does the 150 μA knee current impact low-power system design?

The 150 μA knee current defines the minimum current at which regulation begins - enabling reliable startup and stable output even when driven by high-impedance sources like microcontroller DACs or leakage-limited bias networks. This allows direct interface with ultra-low-power MCUs (e.g., MSP430, STM32L0) without additional current-boosting circuitry.