Analog Devices Inc. AD825AR

Overview

AD825AR from Analog Devices is a high-speed JFET-input operational amplifier optimized for signal conditioning and data acquisition. It delivers 44 MHz −3 dB bandwidth, 125 V/µs slew rate, and 12 nV/√Hz input voltage noise at ±15 V supply, enabling precision buffering in ADC input stages and photo detector interfaces.

For engineers reviewing the AD825AR datasheet, AD825AR pinout, AD825AR application, or AD825AR equivalent, key selection criteria include rail-to-rail input tolerance without phase reversal, 50 mA output drive into capacitive loads, and stable ac performance across ±5 V to ±15 V supplies.

Technical Context

The AD825AR uses a common-drain/common-base FET input stage followed by a cascoded NPN gain stage and Class AB emitter-follower output buffer with internal compensation capacitor (CF) for capacitive load stability. Its input stage prevents phase reversal even when inputs exceed supply rails.

It maintains stable unity-gain bandwidth (23–26 MHz), slew rate (125–140 V/µs), and open-loop gain (70–76 dB) over temperature (−40°C to +85°C) and supply range (±5 V to ±15 V), with low distortion (−76 dB THD at 1 MHz) and high CMRR (71–80 dB).

Key Specifications

Pinout & Package

AD825AR is packaged in an 8-lead SOIC_N (R-8) with 1.27 mm lead pitch per JEDEC MS-012-AA. Pin 1 is NC (no connect); pins 2 and 3 are inverting and non-inverting inputs; pin 4 is negative supply; pins 5 and 8 are NC; pin 6 is output; pin 7 is positive supply.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD825AR, AD825ARZ offers identical performance with RoHS compliance, while OPA656U trades supply flexibility and quiescent current for higher speed and lower noise-making AD825AR optimal for general-purpose high-speed buffering where ±5 V to ±15 V operation and 6.5 mA supply current are critical.

Availability

AD825AR is available at Aetrix Electronics and suitable for CCD signal conditioning, ADC input buffering, and photo detector interfaces requiring stable component supply across industrial temperature ranges (−40°C to +85°C).

Supply support for AD825AR 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 AD825AR belongs to Analog Devices' precision high-speed op-amp product line, designed specifically for demanding signal conditioning in data acquisition, instrumentation, and imaging systems where speed, low noise, and rail-to-rail input integrity are essential.

FAQ

What is the operating temperature range for the AD825AR?

The AD825AR is specified for continuous operation from −40°C to +85°C ambient temperature. This range is validated across all key parameters including bandwidth, slew rate, and input offset voltage, making it suitable for industrial and automotive under-hood environments where thermal stability is critical. The AD825AR datasheet Rev. G confirms this rating in the Absolute Maximum Ratings table.

Does the AD825AR support dual-supply operation at ±5 V?

Yes, the AD825AR is fully specified for dual-supply operation at ±5 V, delivering 34–37 MHz −3 dB bandwidth, 115–130 V/µs slew rate, and −76 dB THD at 1 MHz. Its quiescent current drops to 6.2–6.8 mA at ±5 V, enabling low-power portable instrumentation without sacrificing ac performance. These values are explicitly tabulated in Table 2 of the AD825 datasheet Rev. G.

Can the AD825AR drive a 150 Ω video load without gain degradation?

Yes, the AD825AR maintains stable closed-loop gain and ≤0.1 dB flatness up to 10 MHz into a 150 Ω load, as verified in Figure 21 of the AD825 datasheet Rev. G. Its 50 mA minimum output current and robust output stage ensure full ±3.2 V swing at ±5 V supply into 150 Ω, meeting NTSC differential gain (1.2%) and phase (1.4°) specifications.

Is the AD825AR pin-compatible with the AD825ARZ variant?

Yes, the AD825AR and AD825ARZ share identical pinout, package dimensions (8-lead SOIC_N, R-8), and electrical specifications. The sole difference is RoHS compliance: AD825ARZ features lead-free terminations per JEDEC J-STD-609, while AD825AR is non-RoHS. Both are mechanically and electrically interchangeable in existing PCB layouts.

What is the maximum capacitive load the AD825AR can drive stably?

The AD825AR drives ≥400 pF capacitive loads stably without external compensation, as demonstrated in Figure 31 of the AD825 datasheet Rev. G. Its internal CF capacitor and Class AB output stage maintain phase margin above 60° even under heavy capacitive loading, enabling direct connection to anti-aliasing filters or long cables without series isolation resistors.