Analog Devices Inc. AD823ANZ

Overview

AD823ANZ from Analog Devices is a dual, precision, rail-to-rail output, JFET-input operational amplifier optimized for single-supply operation from 3 V to 36 V (or ±1.5 V to ±18 V). It delivers 16 MHz −3 dB bandwidth (G = +1), 22 V/µs slew rate, and 800 µV max input offset voltage, enabling high-fidelity signal conditioning in battery-powered instrumentation and photodiode preamplifiers.

For engineers reviewing the AD823ANZ datasheet, AD823ANZ pinout, AD823ANZ application, or AD823ANZ equivalent, key selection criteria include its 25 pA max input bias current, 500 pF capacitive load drive capability, rail-to-rail output swing within 25 mV of supplies at light load, and −108 dBc harmonic distortion at 20 kHz - all verified across −40°C to +85°C.

Technical Context

The AD823ANZ employs a complementary bipolar (CB) process with N-channel JFET input stage, delivering picoamp-level input bias current and 16 nV/√Hz input voltage noise at 10 kHz. Its nested integrator topology features Miller compensation (C1, C5) and dual-stage gain architecture, achieving 109 dB open-loop gain and 23 MHz unity-gain bandwidth in the output stage.

This architecture enables simultaneous high dc precision (2 µV/°C offset drift) and ac performance (350 ns settling to 0.01% for 2 V step), while maintaining stability driving up to 500 pF directly - without external isolation resistors - due to controlled output impedance rise and inherent phase margin preservation.

Key Specifications

Pinout & Package

AD823ANZ is housed in an 8-lead PDIP (Plastic Dual In-line Package) with standard dual op amp pinout. The package is through-hole mounted, RoHS-compliant, and rated for industrial temperature operation (−40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual JFET-input op amp applications.

Compared with OPA2134PA and TL072CP, AD823ANZ uniquely combines 16 MHz bandwidth, rail-to-rail output, guaranteed no-phase-inversion to the positive rail, and 25 pA max input bias - making it the only option among the three qualified for precision, high-speed, single-supply photodiode and ADC driver roles.

Availability

AD823ANZ is available at Aetrix Electronics and suitable for battery-powered instrumentation, photodiode preamplifiers, and 12-bit to 16-bit data acquisition systems requiring stable component supply, long-term industrial temperature support (−40°C to +85°C), and RoHS-compliant through-hole packaging.

Supply support for AD823ANZ 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD823 product line delivers dual JFET-input op amps engineered for precision, speed, and single-supply versatility - targeting applications demanding low input bias, rail-to-rail output, and robust capacitive load drive in medical, test equipment, and portable instrumentation.

FAQ

What is the maximum capacitive load the AD823ANZ can drive stably in unity-gain configuration?

The AD823ANZ is specified to drive up to 500 pF capacitively in G = +1 configuration while maintaining stability, as confirmed in Figure 34 and Table 1 of the Rev. E datasheet. This capability eliminates the need for series isolation resistors in typical ADC input buffering applications, though adding a small resistor (e.g., 10–50 Ω) improves phase margin if driving >500 pF or operating at higher gains.

Does the AD823ANZ exhibit phase inversion when input voltages approach the positive supply rail?

No - the AD823ANZ does not exhibit phase inversion for input voltages up to and including +VS, as explicitly stated in the General Description and verified in Figure 38 of the datasheet. This behavior is enabled by its JFET input stage and distinguishes it from many bipolar-input op amps that invert when inputs exceed the supply by even small margins.

What is the input common-mode voltage range of the AD823ANZ when operated on a +5 V single supply?

When operated on a +5 V single supply (with −VS = GND), the AD823ANZ input common-mode voltage range extends from −0.2 V to +3.8 V, per Table 1 in the Rev. E datasheet. This allows inputs to go 200 mV below ground and up to 1.2 V below +VS - supporting true single-supply interfacing with ground-referenced sensors.

Can the AD823ANZ operate from a 3 V single supply, and what performance is guaranteed at that voltage?

Yes - the AD823ANZ is fully specified for 3 V single-supply operation. At +VS = +3.3 V, it delivers 15 MHz −3 dB bandwidth (typ), 20 V/µs slew rate (typ), 300 ns settling to 0.01%, and rail-to-rail output swing from 0.025 V to 3.275 V at ±100 µA load, as detailed in Table 2 of the Rev. E datasheet.

What is the maximum output current the AD823ANZ can deliver while maintaining rail-to-rail swing?

The AD823ANZ delivers 15 mA output current while staying within 0.5 V of the supply rails (e.g., 0.5 V to 4.5 V on +5 V supply), per Table 1. At ±10 mA load, output swing degrades to 0.25 V to 4.75 V - confirming usable rail-to-rail performance up to moderate loads without external boost circuitry.