Diodes Incorporated ZXRE125DRSTOB

Overview

ZXRE125DRSTOB from Diodes Incorporated is a micropower bandgap voltage reference IC delivering a precise 1.220 V output with ±1% initial tolerance, 20 ppm/°C typical temperature coefficient, and stable operation from 4 µA to 20 mA supply current - used in portable instrumentation and battery-powered precision analog signal chains.

For engineers reviewing the ZXRE125DRSTOB datasheet, ZXRE125DRSTOB pinout, ZXRE125DRSTOB application, or ZXRE125DRSTOB equivalent, key selection criteria include low knee current (4 µA), unconditional stability with capacitive loads, SOT23-3 package compatibility, and tolerance-grade traceability for low-power calibration circuits.

Technical Context

The ZXRE125DRSTOB implements a two-terminal bandgap reference topology operating as a shunt regulator, requiring an external current source and load resistor. It achieves precision via curvature-compensated bandgap core design and laser-trimmed resistive elements.

Its unconditionally stable architecture eliminates need for external compensation across capacitive loads up to 10 µF, and it maintains regulation down to 4 µA minimum operating current - enabling use in ultra-low-power wake-up circuits and energy-harvesting systems where quiescent current is critical.

Key Specifications

Pinout & Package

SOT23-3 surface-mount package (3.04 mm × 2.64 mm × 1.12 mm), JEDEC MO-178AA compliant, with gull-wing leads and green molding compound (Br/Sb-free).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACDBVR and MAX6126AASA+, the ZXRE125DRSTOB uniquely balances ultra-low knee current (4 µA), fixed 1.220 V output, and unconditional capacitive stability - making it optimal for space-constrained, battery-critical shunt reference roles where trimmable or series alternatives introduce overhead.

Availability

ZXRE125DRSTOB is available at Aetrix Electronics and suitable for portable instrumentation, battery-powered medical sensors, and industrial loop-powered transmitters requiring stable component supply with long-term manufacturability assurance.

Supply support for ZXRE125DRSTOB 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, cost-optimized components for power management, signal integrity, and precision analog applications.

The ZXRE125 belongs to Diodes' precision voltage reference product line, engineered specifically for ultra-low-power, space-constrained systems where shunt topology, minimal knee current, and guaranteed stability outweigh programmability or ultra-low tempco requirements.

FAQ

What is the correct biasing configuration for ZXRE125DRSTOB in a shunt reference circuit?

The ZXRE125DRSTOB operates as a two-terminal shunt reference: Pin 2 (cathode) connects to the regulated voltage node and load, while Pin 1 (anode) connects to ground. A series current-setting resistor supplies operating current from a higher-voltage rail. Pin 3 is internally unconnected and may be left floating or tied to Pin 1 per layout best practices for thermal symmetry.

Does ZXRE125DRSTOB require an external capacitor for stability?

No - the ZXRE125DRSTOB is unconditionally stable and does not require an external capacitor for stability, even with capacitive loads up to 10 µF. This eliminates layout sensitivity and reduces bill-of-materials count. However, a 100 nF ceramic capacitor is still recommended at the output for high-frequency noise suppression in noisy environments.

How does the ±1% tolerance of ZXRE125DRSTOB impact system-level accuracy?

The ±1% initial tolerance contributes directly to absolute voltage error in the signal chain - e.g., ±12.2 mV at 1.22 V. For 12-bit ADC systems, this represents ~3.3 LSB error before calibration. System-level accuracy can be improved via one-time factory calibration or by selecting tighter-tolerance variants (ZXRE125CFTA, ±0.5%) when higher precision is required.

Can ZXRE125DRSTOB replace ZRA125 series devices in existing designs?

Yes - ZXRE125DRSTOB is explicitly designed as a pin-for-pin compatible replacement for ZRA125 series references in SOT23-3 packages. It matches pinout, electrical envelope, and thermal profile, and offers identical 1.22 V nominal output with improved knee current (4 µA vs. 10 µA) and lower tempco (20 ppm/°C typical vs. 50 ppm/°C typical for ZRA125).