Overview
The ADA4945-1ACPZ-R2, produced by Analog Devices Inc., is a high-performance, low-noise, and low-distortion fully differential amplifier. This device is designed to operate in two selectable power modes, making it versatile for various data acquisition and signal processing applications. It is particularly well-suited for driving high-resolution successive approximation register (SAR) and Σ-Δ analog-to-digital converters (ADCs). The ADA4945-1 features a broad power supply range of 3 V to 10 V, adjustable common-mode voltage, and exceptional output balance due to its internal common-mode feedback loop.
Key Specifications
| Parameter | Test Conditions | Full Power Mode | Low Power Mode |
|---|---|---|---|
| Power Supply Range | 3 V to 10 V | 3 V to 10 V | |
| Quiescent Current | 4 mA | 1.4 mA | |
| Input Voltage Noise | 2.0 nV/√Hz | ||
| Offset Drift | ±0.1 µV/˚C | ±0.1 µV/˚C | |
| Second Harmonic Distortion (HD2) | fC = 1 kHz | -133 dBc | -133 dBc |
| Third Harmonic Distortion (HD3) | fC = 1 kHz | -140 dBc | -140 dBc |
| Settling Time (18-bit) | 100 ns | ||
| Settling Time (16-bit) | 50 ns | ||
| Operating Temperature Range | −40°C to +125°C | −40°C to +125°C | |
| Package | RoHS-compliant, 3 mm × 3 mm, 16-lead LFCSP | RoHS-compliant, 3 mm × 3 mm, 16-lead LFCSP |
Key Features
- Broad power supply range: 3 V to 10 V.
- Wide input common-mode voltage range: −VS to +VS − 1.3 V.
- Rail-to-rail output.
- Two selectable power modes: full power mode (4 mA) and low power mode (1.4 mA).
- Low harmonic distortion: −133 dBc HD2 and −140 dBc HD3 at 1 kHz.
- Fast settling time: 100 ns for 18-bit and 50 ns for 16-bit.
- Input voltage noise: 2.0 nV/√Hz in full power mode.
- Adjustable common-mode voltage to match the input common-mode voltage of multiple ADCs.
- Internal common-mode feedback loop for exceptional output balance and suppression of even order harmonic distortion products.
- Differential gain configurations achieved with a simple external feedback network of four resistors.
- Fabricated using Analog Devices' proprietary silicon germanium (SiGe) complementary bipolar process.
Applications
The ADA4945-1ACPZ-R2 is ideal for driving high-resolution, high-performance successive approximation register (SAR) and Σ-Δ analog-to-digital converters (ADCs). It is also suitable for various data acquisition and signal processing applications where low noise, low distortion, and high accuracy are critical. The adjustable common-mode voltage and internal common-mode feedback loop make it versatile for matching the input common-mode voltage of multiple ADCs.
Q & A
- What is the power supply range of the ADA4945-1?
The ADA4945-1 operates over a broad power supply range of 3 V to 10 V.
- What are the two selectable power modes of the ADA4945-1?
The device can operate in either full power mode (4 mA) or low power mode (1.4 mA).
- What is the input voltage noise of the ADA4945-1 in full power mode?
The input voltage noise is 2.0 nV/√Hz in full power mode.
- How does the ADA4945-1 achieve differential gain configurations?
Differential gain configurations are achieved with a simple external feedback network of four resistors.
- What is the operating temperature range of the ADA4945-1?
The device is specified to operate from −40°C to +125°C.
- What type of package is the ADA4945-1 available in?
The ADA4945-1 is available in a RoHS-compliant, 3 mm × 3 mm, 16-lead LFCSP package.
- What are the key applications of the ADA4945-1?
The device is ideal for driving high-resolution SAR and Σ-Δ ADCs and various data acquisition and signal processing applications.
- How does the ADA4945-1 suppress harmonic distortion?
The internal common-mode feedback loop provides exceptional output balance and suppression of even order harmonic distortion products.
- What is the settling time for 18-bit and 16-bit resolutions?
The settling time is 100 ns for 18-bit and 50 ns for 16-bit resolutions.
- What process is the ADA4945-1 fabricated with?
The device is fabricated using Analog Devices' proprietary silicon germanium (SiGe) complementary bipolar process.
