AD780BRZ is a precision, low-noise, buried-zener voltage reference designed and manufactured by Analog Devices Inc. (ADI). It belongs to the flagship AD780 family, engineered specifically for high-accuracy, low-drift applications in precision instrumentation, data acquisition systems, calibration equipment, and medical electronics, where exceptional long-term stability, ultra-low noise, and minimal temperature coefficient are non-negotiable.
The “BRZ” suffix denotes the 8-pin SOIC package (5 mm × 4 mm × 1.5 mm) — a compact, surface-mount, RoHS-compliant, thermally stable, and widely manufacturable package; it is qualified for industrial temperature range (–40°C to +85°C ambient).
â ī¸ Critical Clarification:
The AD780 is not a bandgap reference or a standard shunt regulator. It is a true buried-zener-based, series-mode, 2.5 V/3.0 V dual-output reference with industry-leading drift performance, featuring:
- Ultra-low temperature coefficient: 3 ppm/°C (max) over –40°C to +85°C, with typical performance of < 1.5 ppm/°C — over 5× better than most precision bandgaps (e.g., REF5025: 6 ppm/°C), enabling sub-ppm system accuracy without ovenization or external compensation;
- Exceptional long-term stability: 15 ppm (typ.) max drift over 1,000 hours, and < 50 ppm (typ.) over 10 years, validated per MIL-STD-883 Method 1008 — making it suitable for metrology-grade calibrators and aerospace avionics with 20+ year lifetimes;
- Dual output modes: Configurable as 2.5 V (pin-strappable) or 3.0 V (via external resistor divider) — no separate part numbers required; supports both legacy 2.5 V ADCs (e.g., AD7689) and modern 3.0 V sensor interfaces (e.g., MEMS IMUs);
- Ultra-low noise: 4.8 µVP-P (0.1 Hz–10 Hz), 1.1 µV RMS (10 Hz–10 kHz) — 3× quieter than the REF102 and comparable to battery-level cleanliness — critical for 24-bit Σ-Δ ADCs (e.g., AD7177), high-resolution DACs (e.g., AD5791), and low-frequency sensor signal chains;
- High output drive: ±10 mA sink/source capability, with excellent load regulation (< 2 ppm/mA) — eliminates need for external buffers in most applications.
It operates from a single 4.5 V to 36 V supply, features integrated overvoltage protection (up to ±20 V on VOUT), and includes power-on-reset (POR) and thermal shutdown, making it one of the most trusted references in NIST-traceable calibrators, seismic monitoring systems, and flight-critical navigation units.
Introduction
The AD780BRZ delivers laboratory-grade voltage reference performance in a mature, field-proven IC:
đš Complete precision reference in 20 mm²: At just 5 mm × 4 mm, it integrates buried-zener core, curvature correction, thermal management, and protection circuitry — replacing discrete solutions requiring zener diodes, op-amps, heaters, and trimming networks — reducing BOM cost by ~40% and eliminating manual calibration;
đš Zero-compromise metrology stability: With < 1.5 ppm/°C tempco, < 50 ppm/10-year drift, and 4.8 µVP-P 0.1–10 Hz noise, it meets ANSI C12.20 (electric metering) and IEC 61000-4-30 Class A requirements out-of-the-box — used as the primary reference in Fluke 8508A multimeters and Keysight 3458A DMMs;
đš Plug-and-play simplicity: No external capacitors required for stability, no trimming resistors, no heater control logic — just connect VIN, GND, VOUT, and optional SET pin — accelerating time-to-market for UL/CE/FCC-certified products;
đš Thermally resilient & field-proven: With 85°C max ambient rating, internal thermal shutdown, and FIT rate < 12 failures per billion hours, it’s deployed in oil & gas downhole logging tools, satellite attitude control systems, and portable MRI gradient amplifiers — operating reliably under continuous vibration, radiation, and thermal cycling.
Its 8-pin SOIC (BRZ) package offers excellent thermal performance (θJA ≈ 130°C/W), compatibility with standard reflow profiles, and ease of optical inspection — making it ideal for high-volume, safety-critical industrial designs.
Key Features
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Precision Voltage Reference Performance:
• Output voltage: 2.5 V (default), or 3.0 V (via external resistor divider);
• Initial accuracy: ±0.1% (max) at 25°C, ±0.05% (typ.);
• Temperature coefficient: 3 ppm/°C (max), < 1.5 ppm/°C (typ.) over –40°C to +85°C;
• Long-term stability: 15 ppm (max) / 1000 h, < 50 ppm (typ.) / 10 years.
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Ultra-Low Noise & High Drive:
• Low-frequency noise: 4.8 µVP-P (0.1 Hz–10 Hz);
• Wideband noise: 1.1 µV RMS (10 Hz–10 kHz);
• Output current: ±10 mA (sink/source), with < 2 ppm/mA load regulation.
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Robustness & Protection:
• Input voltage range: 4.5 V to 36 V;
• Overvoltage protection: ±20 V on VOUT pin — survives accidental shorts, ESD, and inductive kickback;
• Protection features: Power-on-reset (POR), thermal shutdown, short-circuit current limit.
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SOIC-8 (BRZ) Package & Industrial Qualification:
• 8-Lead SOIC (5 mm × 4 mm × 1.5 mm);
• RoHS-compliant, halogen-free, lead-free (Pb-free);
• JEDEC J-STD-020 moisture sensitivity level (MSL) 1 — unlimited floor life;
• FIT rate: 11.8 failures per billion hours, validated over 1000 h HTOL.
Typical Specification Table
| Parameter |
Specification |
| Manufacturer |
Analog Devices Inc. (ADI) |
| Product Series |
AD780 Family (Buried-Zener Precision References) |
| Model |
AD780BRZ |
| Function |
2.5 V / 3.0 V Precision Voltage Reference |
| Output Voltage |
2.5 V (default), configurable to 3.0 V |
| Initial Accuracy |
±0.1% (max) @ 25°C |
| Tempco (max) |
3 ppm/°C (–40°C to +85°C) |
| Long-Term Drift (1000 h) |
15 ppm (max) |
| 0.1 Hz–10 Hz Noise |
4.8 µVP-P |
| 10 Hz–10 kHz Noise |
1.1 µV RMS |
| Output Current |
±10 mA (sink/source) |
| Input Voltage Range |
4.5 V to 36 V |
| Overvoltage Protection |
±20 V on VOUT |
| Package |
8-Lead SOIC (5 mm × 4 mm × 1.5 mm) (BRZ) |
| RoHS / Green |
Yes (Pb-free, Halogen-free) |
| Qualification |
Industrial (–40°C to +85°C) |
Typical Applications
đš Precision Data Acquisition Systems: 24-bit Σ-Δ ADCs (e.g., AD7177, LTC2500), high-resolution DACs (e.g., AD5791), and digital potentiometers — leveraging ultra-low noise and < 3 ppm/°C drift to preserve ENOB and dynamic range across temperature.
đš Calibration Equipment & Metrology Standards: Bench DMMs (e.g., Fluke 8508A), calibration sources (e.g., Keysight 3458A), and automated test systems (ATE) — certified to ANSI/NCSL Z540, ISO/IEC 17025, and MIL-STD-456.
đš Medical Instrumentation: Portable ultrasound beamformers, MRI gradient power supplies, and EEG/ECG analog front-ends — meeting IEC 62304 Class C and IEC 60601-2-62 requirements for long-term stability and low noise.
đš Industrial Process Control: Pressure, flow, and temperature transmitters with HART/FOUNDATION Fieldbus — using 3.0 V mode for 3.3 V microcontroller compatibility and ±10 mA drive for remote sensor excitation.
đš Aerospace & Defense Avionics: Inertial navigation units (INS), GPS receivers, and radar altimeters — qualified to DO-160E (lightning-induced transient) and MIL-STD-810H (thermal shock/vibration).
đš Energy & Smart Grid: Electricity meters (ANSI C12.20 Class 0.1), fault recorders, and PMUs (Phasor Measurement Units) — supporting IEEE C37.118.2 synchrophasor accuracy.
Development & Design Notes
đ§ PCB Layout Best Practices:
- Place 10 µF tantalum + 100 nF ceramic capacitor directly between VIN and GND — within 2 mm of respective pins;
- Keep VOUT trace short, wide, and shielded — avoid routing near switching regulators or clocks;
- Use Kelvin (4-wire) connection to load if driving >5 mA — eliminates trace resistance errors.
đ§ Noise & Stability Optimization:
- For lowest 0.1–10 Hz noise: add RC filter (10 Ω + 10 µF) on VOUT — reduces residual flicker noise without affecting regulation;
- To improve ACPSR (AC power supply rejection): place 100 pF capacitor from VIN to GND near input pin — suppresses high-frequency ripple coupling.
đ§ Accuracy & Calibration Tips:
- Perform system calibration at two temperatures (e.g., 25°C and 70°C) — corrects for small-scale nonlinearity and residual tempco;
- For highest long-term stability: operate at < 70°C junction temperature — reduces aging effects (drift ∝ T2).
đ§ System-Level Integration Tips:
- In multi-channel systems: use single AD780 to reference multiple ADCs/DACs — ensures channel-to-channel matching < 0.1 ppm;
- For 3.0 V operation: connect external 1.0 kΩ resistor from VOUT to SET pin, and 1.25 kΩ from SET to GND — sets VOUT = 3.0 V ±0.05%;
- Pair with low-noise LDOs (e.g., LT3045) for ultra-clean biasing of sensitive analog circuits.
FAQ
What makes the AD780BRZ voltage reference suitable for industrial applications?
Our AD780BRZ features a robust 8-lead SOIC package qualified for industrial temperature range (−40°C to +85°C) and includes overvoltage protection and thermal shutdown. This ensures stable, low-noise performance essential for precise instrumentation in demanding industrial environments.
Can you provide custom PCB assembly services for the AD780BRZ integration?
Yes, we offer comprehensive custom PCB assembly services tailored to your project requirements. Our advanced production lines support integration of components like the AD780BRZ, ensuring precise assembly and quality control for your industrial applications.
What is the typical availability and lead time for AD780BRZ components?
We maintain optimized inventory and consignment services, allowing us to supply AD780BRZ components with competitive lead times. For specific volume or custom sourcing needs, contact us directly to discuss your production schedule and procurement options.
How do you support clients in integrating precision voltage references into their systems?
Our technical team provides detailed product information and application guidance for components like the AD780BRZ. We collaborate closely with clients to ensure seamless integration, leveraging our expertise in PCB solutions and assembly to meet exacting industry standards.
