The Analog Devices AD586KN is a high-precision, 5V voltage reference designed for applications requiring stable, accurate reference voltages with low noise and excellent long-term stability. Part of the AD586 series, it leverages a proprietary ion-implanted buried Zener diode and laser-trimmed high-stability thin-film resistors to deliver outstanding performance at a competitive cost. The AD586KN is a commercial-grade device housed in an 8-pin plastic dual in-line package (PDIP), offering a balance of precision, reliability, and ease of use for industrial, instrumentation, and data acquisition systems. Below is a comprehensive overview of the AD586KN, covering its features, specifications, applications, and operational characteristics in detail.

## Overview

The AD586KN is a monolithic 5V voltage reference that provides a precise, stable output voltage with minimal drift over temperature and time. It is designed to operate with a wide input voltage range and low quiescent current, making it suitable for both battery-powered and line-powered applications. The device’s advanced design, incorporating a buried Zener diode and laser-trimmed resistors, ensures low noise and high accuracy, making it ideal for precision analog circuits, such as analog-to-digital converters (ADCs), digital-to-analog converters (DACs), and calibration systems. The “KN” suffix indicates the commercial temperature range (0°C to 70°C) and a specific accuracy grade, offering tighter specifications than the baseline AD586J.

## Key Features

- High Precision: Delivers a 5V output with an initial accuracy of ±5mV, ensuring reliable performance in precision applications.
- Low Temperature Drift: Minimizes output voltage variation over temperature, with a typical temperature coefficient of 15ppm/°C.
- Low Noise: Provides a low output noise of 4µV p-p (0.1Hz to 10Hz), ideal for noise-sensitive analog circuits.
- Wide Input Voltage Range: Operates with input voltages from 7V to 36V, accommodating various power supply configurations.
- Low Quiescent Current: Consumes only 2mA (typical), enhancing efficiency in low-power applications.
- Built-In Trimming Capability: Includes pins for fine-tuning the output voltage, allowing for calibration to achieve higher accuracy.
- Robust Protection: Features internal protection against reverse polarity and overcurrent conditions.
- Compact Package: Housed in an 8-pin PDIP, suitable for through-hole PCB designs.
- RoHS Compliance: Lead-free construction aligns with environmental standards.

## Detailed Specifications

Below is a detailed list of the electrical, thermal, and physical specifications for the AD586KN:

- Output Voltage: 5.000V (nominal)
- Initial Accuracy: ±5mV (maximum) at TA = 25°C
- Temperature Coefficient: 15ppm/°C (maximum, 0°C to 70°C)
- Output Voltage Noise: 4µV p-p (typical, 0.1Hz to 10Hz)
- Line Regulation: 100µV/V (typical) at VIN = 7V to 36V
- Load Regulation: 100µV/mA (typical) at IOUT = 0mA to 10mA
- Output Current: 10mA (maximum sourcing)
- Input Voltage Range: 7V to 36V
- Quiescent Current: 2mA (typical), 3mA (maximum)
- Long-Term Stability: 15ppm/1000 hours (typical) at TA = 25°C
- Dropout Voltage: 2V (minimum, VIN - VOUT)
- Output Impedance: 0.2Ω (typical)
- Temperature Range: 0°C to 70°C (operating)
- Storage Temperature Range: -65°C to +150°C
- Power Dissipation: 500mW (maximum) at TA = 25°C
- Thermal Resistance (RθJA): 150°C/W (junction-to-ambient, PDIP)
- Package: 8-pin PDIP (N-8)
- Pin Count: 8
- Pin Configuration:
- Pin 1: NC (No Connection)
- Pin 2: VIN (Input Voltage)
- Pin 3: NC (No Connection)
- Pin 4: GND (Ground)
- Pin 5: TRIM (Output Voltage Trim)
- Pin 6: VOUT (Output Voltage)
- Pin 7: NC (No Connection)
- Pin 8: NC (No Connection)
- ESD Protection: 4kV (HBM, Human Body Model)
- Weight: Approximately 0.5g (device weight) + packing material
- RoHS Status: ROHS3 Compliant

## Functional Description

The AD586KN is a series voltage reference that uses a buried Zener diode and laser-trimmed thin-film resistors to produce a stable 5V output. The buried Zener technology provides superior noise performance and long-term stability compared to surface Zener or bandgap references. The device operates by comparing the Zener voltage to a scaled voltage derived from the input supply, using an internal amplifier to regulate the output. The TRIM pin allows for fine adjustment of the output voltage using an external potentiometer or resistor network, enabling calibration to within ±1mV for applications requiring ultra-high precision.

The AD586KN can source up to 10mA of output current, sufficient for driving small loads such as ADC reference inputs or operational amplifier circuits. Its low dropout voltage (2V minimum) ensures stable operation even when the input voltage is close to the output voltage. The device includes internal protection circuitry to guard against reverse polarity and overcurrent conditions, enhancing reliability in rugged environments.

## Applications

The AD586KN is well-suited for a wide range of precision analog applications, including:
- Data Acquisition Systems: Providing a stable reference voltage for ADCs and DACs in industrial and laboratory equipment.
- Instrumentation: Ensuring accurate measurements in multimeters, oscilloscopes, and other test equipment.
- Power Supply Regulation: Serving as a reference for feedback loops in linear and switching power supplies.
- Automotive Electronics: Supporting sensor interfaces and control modules requiring stable voltages in commercial temperature ranges.
- Medical Devices: Powering precision analog circuits in diagnostic and monitoring equipment.
- Calibration Systems: Used as a primary or secondary reference in calibration standards for voltage and current measurements.

## Occupation Characteristics

- High Accuracy: The ±5mV initial accuracy ensures precise voltage output, critical for high-precision applications.
- Low Noise: The 4µV p-p noise performance minimizes interference in sensitive analog circuits, such as those in ADCs and DACs.
- Low Temperature Drift: The 15ppm/°C temperature coefficient ensures stable output across the 0°C to 70°C range, suitable for commercial-grade applications.
- Wide Input Range: The 7V to 36V input range supports a variety of power supply configurations, including battery-powered systems.
- Trim Capability: The TRIM pin allows for fine-tuning to achieve near-perfect 5V output, ideal for calibration applications.
- Low Quiescent Current: The 2mA typical quiescent current enhances efficiency in low-power designs.
- Robust Design: Internal protection features ensure reliability under fault conditions, such as reverse polarity or short circuits.

## Design Considerations

When designing with the AD586KN, engineers should consider the following:
- Input Capacitor: A 0.1µF to 1µF ceramic capacitor should be placed close to the VIN pin to reduce input impedance and improve transient response.
- Output Capacitor: A 1µF to 10µF capacitor on the VOUT pin is recommended to improve stability and reduce noise. Low-ESR ceramic capacitors are preferred.
- Trimming Circuit: For applications requiring higher accuracy, a 10kΩ to 100kΩ potentiometer can be connected to the TRIM pin (Pin 5) to adjust the output voltage by ±15mV. The trim circuit should be designed to minimize noise injection.
- Thermal Management: The PDIP package’s thermal resistance of 150°C/W requires adequate PCB copper area or heatsinking for applications with high ambient temperatures or sustained 10mA output current.
- Bypass Capacitor: In noise-critical applications, a 10nF to 100nF bypass capacitor across VOUT to GND can further reduce high-frequency noise.
- Load Regulation: Ensure load currents remain within 0mA to 10mA to maintain specified regulation performance.
- ESD Precautions: The device is ESD-sensitive (4kV HBM), so proper handling and grounding procedures are necessary during assembly.

## Packaging and Availability

The AD586KN is supplied in tubes for through-hole assembly, with the 8-pin PDIP package measuring approximately 9.8mm x 6.4mm x 3.3mm. The device is RoHS3-compliant and lead-free, meeting modern environmental standards. It is available through major electronics distributors, with pricing and availability varying based on order volume and market demand. The “KN” grade is part of the commercial product line, but the AD586 series also includes other grades (e.g., AD586L, AD586M) with tighter specifications for more demanding applications.

## Advantages

- High Precision: The ±5mV initial accuracy and 15ppm/°C temperature coefficient make it ideal for precision analog systems.
- Low Noise: The 4µV p-p noise performance ensures clean reference voltages for sensitive applications.
- Flexible Input Range: The 7V to 36V input range supports diverse power supply configurations.
- Trim Capability: Allows calibration for ultra-high accuracy, critical for instrumentation and calibration systems.
- Reliable Operation: Internal protection and robust design ensure long-term reliability in commercial environments.

## Limitations

- Fixed Output Voltage: The 5V output is fixed, limiting flexibility compared to adjustable references like the AD584.
- Temperature Range: The 0°C to 70°C range is suitable for commercial applications but less robust than the AD586S/T grades (-55°C to +125°C).
- Output Current: The 10mA maximum output current restricts its use to low-current applications.
- Through-Hole Package: The PDIP package is less suitable for modern surface-mount designs compared to SOIC or cerdip variants.

## Comparison with Related Devices

The AD586KN can be compared to other Analog Devices voltage references, such as the AD584 (pin-programmable 2.5V, 5V, 7.5V, 10V outputs) or the AD780 (2.5V/3V ultra-high precision reference). The AD586KN offers better noise performance (4µV p-p vs. 10µV p-p for AD584) but is less flexible due to its fixed 5V output. Compared to the AD780, the AD586KN is less precise (15ppm/°C vs. 3ppm/°C) but more cost-effective for commercial applications. Against competitors like the Texas Instruments REF5050 or Maxim’s MAX6250, the AD586KN provides comparable performance but benefits from Analog Devices’ proprietary Zener technology for superior noise and stability.

## Conclusion

The Analog Devices AD586KN is a high-precision 5V voltage reference tailored for commercial applications requiring stable, low-noise reference voltages. Its buried Zener diode technology, laser-trimmed resistors, and low temperature drift make it an excellent choice for data acquisition systems, instrumentation, and power supply regulation. The ±5mV initial accuracy, 4µV p-p noise, and trimming capability ensure high performance, while the wide input voltage range and low quiescent current enhance versatility. Although limited by its fixed output and commercial temperature range, the AD586KN’s combination of precision, reliability, and cost-effectiveness makes it a robust solution for a wide range of analog and mixed-signal applications.