AD8655ARZ - Low Noise Precision CMOS Op Amp | Analog Devices
N.º de pieza: AD8655ARZ ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $2.94 | $2,94 |
| 10 | $2.65 | $26,50 |
| 100 | $2.36 | $236,00 |
| 500 | $2.12 | $1.060,00 |
| 1.000 | $1.91 | $1.910,00 |
AD8655ARZ Descripción general
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 buffering. The AD8655ARZ belongs to the category of precision CMOS amplifiers, which are known for their low offset voltage, low noise, and high input impedance. In the hierarchy of amplifiers, it sits under general-purpose op amps, which are widely used in instrumentation, audio, and sensor interfaces.
The AD8655 leverages Analog Devices' DigiTrim technology to achieve high DC accuracy, with a maximum offset voltage of 250 µV over the common-mode voltage range. It also features low total harmonic distortion plus noise (THD+N) of 0.0007%, ensuring high fidelity in audio and precision measurement applications. The rail-to-rail input and output capability allows the amplifier to operate with minimal headroom, maximizing dynamic range in low-voltage systems.
From a technical perspective, the AD8655 is fabricated in a CMOS process, which provides low input bias current and high input impedance. The DigiTrim technology trims the input offset voltage at the wafer level, reducing the need for external calibration. The amplifier is stable with capacitive loads up to 100 pF, and its output can swing within 10 mV of the supply rails. The device also includes internal ESD protection and is specified for operation over the industrial temperature range of -40°C to +125°C.
Typical applications include precision sensor signal conditioning, portable medical devices, audio preamplifiers, and active filters. The low noise and high precision make it ideal for amplifying small signals from sensors such as thermocouples, strain gauges, and photodiodes. In audio applications, the low THD+N ensures transparent signal reproduction.
When designing with the AD8655ARZ, it is important to provide adequate power supply decoupling with 0.1 µF ceramic capacitors placed close to the V+ and V- pins. Additionally, the input common-mode voltage should be kept within the specified range to avoid output phase reversal. The rail-to-rail output stage can drive moderate loads, but for heavy loads, a buffer or higher-current amplifier may be required.
Alternativas directas para AD8655ARZ — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con AD8655ARZ (mismo factor de forma y huella) — difiere en Slew Rate, Amplifier Type, Number of Channels, Package, Supply Voltage Range.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
AD8655ARZ-REEL
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
AD8656ARZ
⚡ Mismo encapsulado✓ En stock
$1.82 / unidad
Ver hoja de datos →AD8626ARZ
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
OPA2134UA/2K5
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$1.45 / unidad
Ver hoja de datos →AD8605ARZ-REEL7
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$0.78 / unidad
Ver hoja de datos →AD8655ARZ Valores máximos y características eléctricas
| Amplifier Type | General Purpose |
| Number of Circuits | 1 |
| Tipo de salida | Rail-to-Rail |
| Slew Rate | 11 V/µs |
| Gain Bandwidth Product | 28 MHz |
| Current - Input Bias | 1 pA |
| Voltage - Input Offset | 250 µV max |
| Current - Supply | 4.5 mA |
| Current - Output / Channel | 220 mA |
| Voltage - Supply Span (Min) | 2.7 V |
| Voltage - Supply Span (Max) | 5.5 V |
| Temperatura de funcionamiento | -40°C to +125°C |
| Encapsulado / Carcasa | 8-SOIC |
| Tipo de montaje | Surface Mount |
| Densidad de ruido | 2.7 nV/√Hz at 10 kHz |
| THD+N | 0.0007% |
Configuración de pines de AD8655ARZ
| Pin 1 | OUT — Amplifier output |
| Pin 2 | -IN — Inverting input |
| Pin 3 | +IN — Non-inverting input |
| Pin 4 | V- — Negative supply |
| Pin 5 | NC — No connect |
| Pin 6 | NC — No connect |
| Pin 7 | V+ — Positive supply |
| Pin 8 | NC — No connect |
Aplicaciones típicas
AD8655ARZ es adecuado para 6 aplicacións: Precision Sensor Signal Conditioning, Portable Medical Devices, Audio Preamplifiers, Active Filters, Battery-Powered Instrumentation, Photodiode Amplifier.
Precision Sensor Signal Conditioning
The AD8655ARZ's low offset voltage (250 µV max) and low noise (2.7 nV/√Hz) make it ideal for amplifying small signals from sensors such as thermocouples, strain gauges, and photodiodes. Its rail-to-rail input and output allow direct interfacing with ADCs and microcontrollers. The CMOS input provides high impedance, minimizing loading on the sensor. For best performance, use a low-pass filter at the output to reduce high-frequency noise. The amplifier's 28 MHz bandwidth ensures fast response for dynamic measurements.
Recomendado
Portable Medical Devices
The AD8655ARZ operates from 2.7 V to 5.5 V, making it suitable for battery-powered medical devices like glucose monitors and pulse oximeters. Its low power consumption (4.5 mA) extends battery life. The low noise and high precision ensure accurate measurement of physiological signals. The rail-to-rail output allows direct connection to low-voltage ADCs. For safety, ensure proper isolation and ESD protection in the design. The small 8-SOIC package saves board space in compact devices.
Recomendado
Audio Preamplifiers
With a THD+N of 0.0007% and low noise, the AD8655ARZ is excellent for audio preamplifiers and headphone amplifiers. It provides high fidelity signal amplification with minimal distortion. The rail-to-rail output maximizes dynamic range, and the 28 MHz bandwidth ensures accurate reproduction of high-frequency audio. For optimal performance, use high-quality passive components and proper grounding. The amplifier can drive headphones directly with its 220 mA output current capability.
Recomendado
Active Filters
The AD8655ARZ's 28 MHz gain-bandwidth product makes it suitable for active filters in communication and instrumentation systems. It can implement low-pass, high-pass, and band-pass filters with high accuracy. The low noise ensures minimal signal degradation. The rail-to-rail output allows wide dynamic range. For filter design, use precision resistors and capacitors to achieve desired cutoff frequencies. The amplifier's stability with capacitive loads up to 100 pF simplifies filter implementation.
Recomendado
Battery-Powered Instrumentation
The AD8655ARZ's low supply voltage (2.7 V to 5.5 V) and moderate supply current (4.5 mA) make it ideal for battery-powered instruments like multimeters and data loggers. Its precision and low noise ensure accurate measurements. The rail-to-rail input and output allow full-scale signal handling. For extended battery life, consider powering down the amplifier when not in use. The 8-SOIC package is compact and suitable for portable designs.
Recomendado
Photodiode Amplifier
The AD8655ARZ's low input bias current (1 pA) and low noise make it ideal for transimpedance amplifiers used with photodiodes. It can convert small photocurrents into usable voltage signals with high accuracy. The CMOS input minimizes leakage current, preserving signal integrity. The 28 MHz bandwidth supports high-speed optical communication. For stability, place a feedback capacitor in parallel with the feedback resistor to compensate for input capacitance. The rail-to-rail output allows direct interface with ADCs.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para AD8655ARZ — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | AD8655ARZ-REEL | AD8656ARZ | AD8626ARZ | OPA2134UA | AD8605ARZ-REEL7 |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Texas Instruments | Analog Devices |
| Number of Channels | 1 | 1 | 2 | 2 | 2 | 1 |
| Gain Bandwidth Product | 28 MHz | 28 MHz | 28 MHz | 5 MHz | 8 MHz | 10 MHz |
| Slew Rate | 11 V/µs | 11 V/µs | 11 V/µs | 2.5 V/µs | 20 V/µs | 5 V/µs |
| Voltage Noise Density | 2.7 nV/√Hz | 2.7 nV/√Hz | 2.7 nV/√Hz | 12 nV/√Hz | 8 nV/√Hz | 7 nV/√Hz |
| Input Offset Voltage (max) | 250 µV | 250 µV | 250 µV | 350 µV | 500 µV | 250 µV |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | ±2.5 V to ±18 V | 2.7 V to 5.5 V |
Diferenciadores clave
- Lowest noise in its class (frente a AD8626ARZ)
- Higher bandwidth (frente a AD8605ARZ-REEL7)
- Lower THD+N (frente a OPA2134UA)
Notas de diseño
The AD8655ARZ operates from 2.7 V to 5.5 V. Use a clean power supply with adequate decoupling. Place a 0.1 µF ceramic capacitor close to the V+ and V- pins to filter high-frequency noise. For best performance, use a low-ESR tantalum or ceramic capacitor of 10 µF in parallel for bulk decoupling.
For optimal noise performance, keep the input traces short and shielded. Use a ground plane to minimize noise pickup. Place the feedback resistor and capacitor close to the inverting input to reduce parasitic capacitance. Avoid routing high-speed digital traces near the input pins.
Do not exceed the absolute maximum supply voltage of 6 V. Ensure the input common-mode voltage stays within the specified range to avoid output phase reversal. The output can drive capacitive loads up to 100 pF; for larger loads, add a series resistor to maintain stability.
Información de cumplimiento
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.
