Texas Instruments REF35125YBHR

Overview

REF35125YBHR from Texas Instruments is a nanopower, high-precision series voltage reference delivering 1.25V output with ±0.05% initial accuracy, 10ppm/°C max temperature coefficient (−40°C to +85°C), and 650nA typical quiescent current in a 4-pin WCSP package. It supports precision sensor biasing and 12–16-bit data converter power supply in portable industrial instrumentation.

For engineers reviewing the REF35125YBHR datasheet, REF35125YBHR pinout, REF35125YBHR application, or REF35125YBHR equivalent, key selection criteria include ultra-low IQ, low thermal hysteresis (70ppm), 3.3ppm_P-P 0.1Hz–10Hz noise, EN/NR pin control, and WCSP footprint suitability for space-constrained PCBs.

Technical Context

The REF35125YBHR implements a bandgap-based series reference architecture with integrated enable (EN) and noise reduction (NR) terminals. Its 10ppm/°C tempco is specified over −40°C to +85°C - tighter than the SOT-23 variant's 12ppm/°C - and it achieves 40ppm long-term stability at 1k hour under 35°C bias.

It operates from V_IN = V_REF + V_DO (min 1.7V for 1.25V output) up to 6V, delivers ±5mA sink/source capability, and maintains 20ppm/mA load regulation while supporting 0.1µF–10µF output capacitance with ESR ≤400mΩ.

Key Specifications

Pinout & Package

REF35125YBHR uses a 4-pin Wafer Chip Scale Package (WCSP) with nominal body size 1.05mm × 0.84mm. The package has no exposed pad and requires standard reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF35125YBHR, REF34125RTER offers superior temperature stability at higher current cost, while ADR3412ARJZ-R7 trades output voltage flexibility and control features for minimal IQ - making REF35125YBHR optimal for compact, battery-operated 1.25V-referenced systems requiring dynamic power management.

Availability

REF35125YBHR is available at Aetrix Electronics and suitable for flow transmitter design, blood glucose monitoring, servo drive control modules, and power quality analyzers requiring stable component supply across industrial temperature ranges and long product lifecycles.

Supply support for REF35125YBHR 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision analog ICs and voltage references.

The REF35 family was designed specifically for ultra-low-power, high-accuracy applications in portable instrumentation and industrial sensing - prioritizing nanopower operation, low thermal hysteresis, and miniature WCSP packaging without sacrificing precision.

FAQ

What is the maximum operating temperature range for REF35125YBHR?

The REF35125YBHR is functional from −55°C to +125°C and fully specified for operation from −40°C to +85°C. Its 10ppm/°C temperature coefficient applies within the −40°C to +85°C range, making it suitable for industrial environments where ambient extremes are constrained but reliability is critical. REF35125YBHR maintains performance across this range without derating.

Does REF35125YBHR require an external capacitor on the NR pin?

No, the NR pin of REF35125YBHR may be left floating. However, connecting a capacitor (typically 1µF to 10µF) between NR and GND reduces 0.1Hz–10Hz output noise - e.g., lowering 3.3ppm_P-P to sub-2ppm_P-P - which is beneficial in high-resolution sensor biasing. REF35125YBHR remains fully operational with NR open.

What is the dropout voltage specification for REF35125YBHR at 10mA load?

The dropout voltage for REF35125YBHR is 250mV maximum at 10mA output current. This means VIN must be ≥1.5V (1.25V + 0.25V) to maintain regulation. At 5mA, dropout is 120mV max. These values ensure compatibility with low-voltage rails like 1.8V or 2.5V supplies while delivering full 10mA sourcing capability.

Can REF35125YBHR sink current, and what is its maximum sink capability?

Yes, REF35125YBHR can sink up to 5mA. This bidirectional output capability allows it to serve as a precision reference in circuits requiring both sourcing (e.g., ADC reference) and sinking (e.g., current-source DAC biasing). Load regulation is specified at 40–350ppm/mA for sinking, ensuring predictable behavior under reverse-current conditions.

How does the WCSP package of REF35125YBHR impact PCB layout and thermal performance?

The 4-pin WCSP package (1.05mm × 0.84mm) of REF35125YBHR minimizes board area but requires careful stencil design and reflow profiling due to its small pitch and lack of leads. Thermal resistance R_θJA is 178.9°C/W - higher than SOT-23 - so layout should maximize copper area under the die for heat spreading. REF35125YBHR does not require a thermal pad, simplifying assembly.