Diodes Incorporated ZRC400A01STOB

Overview

ZRC400A01STOB from Diodes Incorporated is a precision 4.096 V bandgap voltage reference IC with ±1% initial tolerance, 30 ppm/°C typical temperature coefficient, and 0.4 Ω typical slope resistance. It operates from 23 µA to 5 mA, requires no external capacitor, and achieves stable output in <10 µs-ideal for low-power battery-operated instrumentation and portable metering systems.

For engineers reviewing the ZRC400A01STOB datasheet, ZRC400A01STOB pinout, ZRC400A01STOB application, or ZRC400A01STOB equivalent, key selection criteria include knee current (18 µA typ), load stability without capacitance, transient response under 10 µs, TC performance across –40°C to +85°C, and SOT23-3 package compatibility with space-constrained PCB layouts.

Technical Context

The ZRC400A01STOB implements a two-terminal shunt topology, functioning as a precision reverse-biased reference with programmable current sink capability. Its bandgap core delivers 4.096 V nominal output with minimal drift over temperature and load variations.

It exhibits low dynamic impedance (0.3–0.8 Ω at 100 Hz) and wideband noise of 90 µV_rms (10 Hz–10 kHz), enabling high-accuracy ADC/DAC biasing and sensor excitation where reference stability directly impacts measurement fidelity.

Key Specifications

Pinout & Package

Package: SOT23-3 (suffix 'F' per ordering table; STOB denotes tape-and-reel packaging). Pin configuration matches standard SOT23-3 outline with anode (pin 1), cathode (pin 2), and floating/connected pin 3 (as per E-Line variant documentation).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL431CDBZR and REF3040AIDBZR, the ZRC400A01STOB uniquely combines fixed 4.096 V output, sub-20 µA knee current, and true two-terminal operation-enabling direct replacement of Zener diodes in legacy designs while delivering superior TC and noise performance.

Availability

ZRC400A01STOB is available at Aetrix Electronics and suitable for battery-powered instrumentation, portable test equipment, smart metering systems, and field calibration tools requiring stable component supply with tight initial tolerance and low-temperature drift.

Supply support for ZRC400A01STOB 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 semiconductor company specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and protection applications.

The ZRC400 series belongs to Diodes' precision voltage reference product line, engineered specifically for space-constrained, low-power measurement systems where shunt topology, capacitor-free operation, and fast settling are essential design requirements.

FAQ

What is the maximum capacitive load the ZRC400A01STOB can drive without instability?

The ZRC400A01STOB is specified as stable with capacitive loads up to 100 nF without external compensation. This is verified in the datasheet's "Stable with Capacitive Loads" section and confirmed by transient response plots showing monotonic settling under 10 µs even with 47 nF ceramic output capacitance. No series resistance or isolation is required for typical ADC input networks.

Can the ZRC400A01STOB be used in a series (three-terminal) configuration?

No-the ZRC400A01STOB is strictly a two-terminal shunt reference and lacks an independent ground or adjust pin. It cannot function as a series regulator or adjustable reference. Any attempt to insert it in series with a load will prevent proper current sinking and cause output collapse. It must be connected between supply and ground with load referenced to its cathode.

Does the ±1% tolerance apply over temperature or only at 25°C?

The ±1% tolerance is the initial accuracy at 25°C, as stated in the ordering table and electrical characteristics table. Total error over –40°C to +85°C includes both initial tolerance and temperature drift (30 ppm/°C typ), resulting in a worst-case deviation of approximately ±1.3% across the full industrial temperature range, assuming typical TC behavior.

Is pin 3 of the SOT23-3 package electrically connected internally?

No-pin 3 is internally unconnected (NC) in the SOT23-3 variant (suffix 'F'). The datasheet's connection diagrams clarify that pin 3 is either floating or optionally tied to pin 1 for thermal symmetry; it carries no functional signal or current path. PCB layout should treat it as non-functional unless explicitly bonded per custom thermal design requirements.