AD8605ARZ - Precision CMOS Rail-to-Rail Op Amp | ADI
N.º da peça: AD8605ARZ ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $3.25 | $3,25 |
| 10 | $2.88 | $28,80 |
| 100 | $2.35 | $235,00 |
| 500 | $2.02 | $1.010,00 |
| 1.000 | $1.79 | $1.790,00 |
AD8605ARZ Visão geral
An operational amplifier (op amp) is a high-gain voltage amplifier with differential inputs and a single-ended output. It is a fundamental building block in analog electronics, used in signal conditioning, filtering, and amplification. The AD8605ARZ belongs to the precision op amp category, which emphasizes low offset, low noise, and high accuracy, distinguishing it from general-purpose amplifiers. As a rail-to-rail input/output CMOS amplifier, it maintains high input impedance and maximizes dynamic range in single-supply systems.
Key features of the AD8605ARZ include a maximum input offset voltage of 65 µV, an input bias current of 1 pA, and a gain-bandwidth product of 10 MHz. The rail-to-rail input and output capability allows the amplifier to operate with the full supply voltage range, maximizing dynamic range in 3 V and 5 V systems. The low input voltage noise density of 7 nV/√Hz and low distortion make it suitable for audio, medical, and precision instrumentation applications. The device uses Analog Devices' patented DigiTrim® trimming technique, which achieves superior precision without laser trimming, resulting in excellent offset voltage and drift performance.
The CMOS input stage provides very high input impedance, minimizing loading on high-impedance sources such as sensors and photodiodes. Typical applications include photodiode amplifiers, high-impedance sensor interfaces, active filters, audio signal conditioning, and portable medical devices. The 10 MHz gain-bandwidth product enables adequate bandwidth for data acquisition systems while preserving low-power operation.
When designing with the AD8605ARZ, ensure proper power supply decoupling with 0.1 µF capacitors placed close to the supply pins. The rail-to-rail output can swing within a few millivolts of the rails, but avoid driving loads that require current beyond the specified output current capability. The 2.7 V minimum supply makes the part ideal for Li-ion and 3.3 V regulated systems.
Alternativas drop-in para AD8605ARZ — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com AD8605ARZ (mesmo formato e footprint) — diferindo em Package, Input Bias Current, Amplifier Type, Gain Bandwidth Product, Input Voltage Noise Density.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
ADA4522-1ARZ
⚡ Mesmo encapsulamento ⚠️ Especificações não verificadas✓ Em estoque
$1.42 / unidade
Ver ficha técnica →OPA376AID
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
OPA365AID
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
MAX4475ASA
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
LMP7701MA/NOPB
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
MCP6V11-E/SN
⚡ Mesmo encapsulamento ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
AD8605ARZ Classificações máximas e características elétricas
| Amplifier Type | Precision CMOS |
| Number of Circuits | 1 |
| Tipo de saída | Rail-to-Rail |
| Input Type | Rail-to-Rail |
| Supply Voltage Range | 2.7 V to 5.5 V |
| Maximum Input Offset Voltage | 65 µV |
| Input Bias Current | 1 pA |
| Input Voltage Noise Density | 7 nV/√Hz |
| Gain Bandwidth Product | 10 MHz |
| Trim Technique | DigiTrim® |
| Encapsulamento | SOIC-8 |
| Tipo de montagem | Surface Mount |
| Status RoHS | Compliant (Pb-free Z suffix) |
Configuração de pinos do AD8605ARZ
| Pino 1 | OUT — Amplifier output |
| Pino 2 | -IN — Inverting input |
| Pino 3 | +IN — Non-inverting input |
| Pino 4 | V- — Negative supply / ground |
| Pino 5 | NC — No connect |
| Pino 6 | NC — No connect |
| Pino 7 | NC — No connect |
| Pino 8 | V+ — Positive supply 2.7 V to 5.5 V |
Aplicações típicas
AD8605ARZ é adequado para 6 aplicaçãos: Photodiode Amplifier (Transimpedance), Battery-Powered Portable Instrumentation, Active Filters in Data Acquisition, Audio Signal Conditioning, High-Impedance Sensor Interface, Portable Medical and Pulse Oximetry.
Photodiode Amplifier (Transimpedance)
The AD8605ARZ is ideal for photodiode transimpedance stages because its 1 pA input bias current reduces photodiode dark-current error, and the 7 nV/√Hz voltage noise preserves signal-to-noise ratio for small photocurrents. The 10 MHz gain-bandwidth product supports fast optical sensing and pulse oximetry. In a typical TIA, place the photodiode between the inverting input and virtual ground, with a feedback resistor RF and a small parallel capacitor CF for phase compensation. The rail-to-rail output then drives a 16-bit ADC such as the AD7685BCPZ.
Recomendado
Battery-Powered Portable Instrumentation
With a 2.7 V to 5.5 V supply range and rail-to-rail input/output, the AD8605ARZ directly operates from a single Li-ion cell or a 3.3 V regulator. Its 1 pA bias current and 65 µV max offset allow accurate conditioning of bridge sensors and thermocouples without complex auto-zero circuits. The 10 MHz bandwidth is sufficient for portable data-acquisition channels while the CMOS input keeps power consumption low. Paired with a low-power ADC such as the AD7685BCPZ, the op amp meets the accuracy and battery-life goals of handheld instruments.
Recomendado
Active Filters in Data Acquisition
The AD8605ARZ is well suited for active filter stages in data acquisition because its rail-to-rail output preserves signal swing and its 10 MHz gain-bandwidth product allows accurate filter responses up to several hundred kilohertz. Low offset and low noise make it appropriate for second-order Sallen-Key or multiple-feedback low-pass filters placed before an ADC. The 1 pA bias current simplifies DC coupling when using high-value resistors. The amplifier can drive the input of a 16-bit ADC like the AD7685BCPZ directly when the filter is followed by a suitable anti-aliasing stage.
Recomendado
Audio Signal Conditioning
The AD8605ARZ is a practical choice for audio line drivers and headphone buffer front-ends because of its 7 nV/√Hz voltage noise, low distortion, and 10 MHz bandwidth. The rail-to-rail input/output stage maximizes headroom in 3.3 V or 5 V audio systems, and the low 1 pA bias current avoids DC offset when AC-coupling is not used. In a 2-pole Sallen-Key low-pass filter or a differential receiver, the AD8605ARZ provides clean signal conditioning. For stereo channels, two devices are used or the dual AD8606ARZ can be selected.
Recomendado
High-Impedance Sensor Interface
The CMOS input stage of the AD8605ARZ, with only 1 pA of input bias current, is ideal for buffering high-impedance sensors such as pH probes, electrochemical sensors, and piezoelectric elements. The very high input impedance minimizes loading and preserves the sensor signal. The rail-to-rail output allows the buffered signal to use the full ADC input range. The low offset and low noise maintain measurement accuracy across temperature. It can directly drive the inputs of precision ADCs such as the AD7793BRUZ in industrial sensing systems.
Recomendado
Portable Medical and Pulse Oximetry
The AD8605ARZ is appropriate for portable medical devices including pulse oximeters and ECG front ends because of its low voltage noise, low input bias current, and wide 2.7 V to 5.5 V supply range. In a pulse oximeter, the op amp amplifies the small photodiode signal while the 1 pA bias current minimizes leakage error. Its 10 MHz bandwidth preserves the shape of fast plethysmographic pulses. The rail-to-rail output directly interfaces with low-voltage ADCs. For multichannel vital-sign monitors, the quad AD8608ARZ or dual AD8606ARZ can cover more channels.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para AD8605ARZ — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | ADA4522-1ARZ | OPA376AID | OPA365AID | MAX4475ASA | LMP7701MA/NOPB | MCP6V11-E/SN |
|---|---|---|---|---|---|---|---|
| Package | SOIC-8 | SOIC-8 | SOIC-8 | SOIC-8 | SOIC-8 | SOIC-8 | SOIC-8 |
| Brand | Analog Devices | Analog Devices | Texas Instruments | Texas Instruments | Maxim Integrated | Texas Instruments | Microchip Technology |
| Supply Voltage Range | 2.7 V to 5.5 V | 4.5 V to 55 V | 2.2 V to 5.5 V | 2.2 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 12 V | 2.2 V to 5.5 V |
| Input Bias Current | 1 pA | 50 pA | 0.2 pA | 2 pA | 1 pA | 1 pA | 20 pA |
| Gain Bandwidth Product | 10 MHz | 6 MHz | 5.5 MHz | 50 MHz | 10 MHz | 2.5 MHz | 80 kHz |
| Input Voltage Noise Density | 7 nV/√Hz | 5.8 nV/√Hz | 7.5 nV/√Hz | 4.5 nV/√Hz | 4.5 nV/√Hz | 8.5 nV/√Hz | 55 nV/√Hz |
| Rail-to-Rail Input/Output | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Principais diferenciais
- Very low 1 pA input bias current in a CMOS rail-to-rail SOIC-8 op amp (vs OPA365AID)
- 10 MHz gain-bandwidth product while drawing low supply current (vs LMP7701MA/NOPB)
- Operates down to 2.7 V for single-supply battery systems (vs ADA4522-1ARZ)
Notas de projeto
Place a 0.1 µF ceramic decoupling capacitor close to the V+ and V- pins of the AD8605ARZ. For best performance, connect a 1 µF to 10 µF bulk capacitor near the supply entry point. The device operates from 2.7 V to 5.5 V; ensure the supply voltage never exceeds 5.5 V to avoid damage. Good decoupling prevents high-frequency supply noise from coupling into the low-noise CMOS input stage.
For high-impedance sensor applications, use guard rings around the inverting and non-inverting inputs to reduce leakage current. Keep traces short and shielded from digital signals. The 1 pA input bias current can be degraded by board contamination, so clean the PCB and use low-leakage solder mask. Place the feedback resistor close to the inverting input to minimize parasitic capacitance.
Do not drive loads that exceed the output current capability, and remember that rail-to-rail output swing is not perfectly to the rails under heavy load. The AD8605ARZ is not a zero-drift amplifier, so DC offset drift may matter in very high-gain applications. For high-frequency photodiode circuits, add a feedback capacitor across the feedback resistor to prevent oscillation and ensure stability.
The 7 nV/√Hz input voltage noise of the AD8605ARZ is suitable for low-noise signal chains, but keep source resistance low enough that resistor thermal noise does not dominate. In a transimpedance or filter stage, calculate the total noise at the output and verify the signal-to-noise ratio. Use metal-film resistors and avoid carbon composition for precision stages.
Informações de conformidade
The 'Z' suffix in AD8605ARZ indicates a lead-free (Pb-free) finish. RoHS compliance is typical for ADI Z-suffix parts, but full REACH and conflict minerals data was not found in the provided source data.
