Overview
The AD797ANZ, produced by Analog Devices Inc., is a very low noise, low distortion operational amplifier. It is ideal for use as a preamplifier, particularly in applications requiring high dynamic range and low distortion. The AD797 features an exceptionally low input voltage noise of 0.9 nV/√Hz and a total harmonic distortion of −120 dB at audio frequencies, making it suitable for critical applications such as professional audio equipment, infrared (IR) and sonar imaging, and ultrasound preamplifiers.
Key Specifications
| Parameter | Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Input Voltage Noise | 1 kHz | - | 0.9 | 1.2 | nV/√Hz |
| Total Harmonic Distortion | f = 20 kHz, 3 V rms, RLOAD = 1 kΩ | -120 | - | - | dB |
| Slew Rate | - | - | 20 | - | V/μs |
| Gain Bandwidth | G = 1000 | - | 110 | - | MHz |
| Input Offset Voltage | ±5 V, ±15 V | 10 | 80 | 125/180 | μV |
| Input Bias Current | ±5 V, ±15 V | 0.25 | 1.5 | 3.0 | μA |
| Supply Voltage | - | ±5 | - | ±18 | V |
| Quiescent Current | ±5 V, ±15 V | 8.2 | 10.5 | - | mA |
| Settling Time (16-bit) | 10 V step | - | 800 | - | ns |
Key Features
- Ultralow noise: 0.9 nV/√Hz at 1 kHz and 50 nV p-p in the 0.1 Hz to 10 Hz bandwidth.
- Low total harmonic distortion: −120 dB at 20 kHz.
- High slew rate: 20 V/μs.
- High gain bandwidth: 110 MHz (G = 1000).
- Excellent settling time: 800 ns to 16 bits for a 10 V step.
- High output current drive: up to 50 mA.
- Wide power supply voltage range: ±5 V to ±18 V.
- Distortion cancellation through a single capacitor (CN).
Applications
- Professional audio preamplifiers and mixing consoles.
- Infrared (IR) and sonar imaging systems.
- Ultrasound preamplifiers.
- Spectrum analyzers and seismic detectors.
- Buffering inputs to Σ-Δ ADCs or outputs of high resolution DACs.
Q & A
- What is the typical input voltage noise of the AD797?
The AD797 has a typical input voltage noise of 0.9 nV/√Hz at 1 kHz. - What is the total harmonic distortion of the AD797 at 20 kHz?
The total harmonic distortion of the AD797 is −120 dB at 20 kHz with a 3 V rms output and a 1 kΩ load. - What is the slew rate of the AD797?
The slew rate of the AD797 is 20 V/μs. - What is the gain bandwidth of the AD797?
The gain bandwidth of the AD797 is 110 MHz for a gain of 1000. - What is the input offset voltage of the AD797?
The input offset voltage of the AD797 is typically 80 μV with a range of 10 μV to 125/180 μV over temperature. - What is the quiescent current of the AD797?
The quiescent current of the AD797 is typically 10.5 mA for ±5 V to ±15 V supply voltages. - What is the settling time of the AD797 to 16 bits?
The settling time of the AD797 to 16 bits is 800 ns for a 10 V step. - What is the maximum output current drive of the AD797?
The AD797 can drive up to 50 mA of output current. - What are the typical applications of the AD797?
The AD797 is typically used in professional audio preamplifiers, IR and sonar imaging, ultrasound preamplifiers, spectrum analyzers, and seismic detectors. - How does the AD797 achieve distortion cancellation?
The AD797 achieves distortion cancellation through the addition of a single capacitor (CN) which cancels distortion due to the output stage.
