優勢和特點

• Fully specified dual power mode operation
  • 4 mA full power mode (200 MHz)
  • 1.4 mA low power mode (80 MHz)
• Full power mode
  • Low harmonic distortion
  • ?140 dB THD at 1 kHz
  • ?120 dB THD at 100 kHz
• Fast settling time
  • 18-bit: 100 ns
  • 16-bit: 50 ns

• Input voltage noise: 1.6 nV/√Hz, f = 100 kHz
• ±50 μV maximum offset voltage from ?40°C to +125°C
• Rail-to-rail output
• Wide input common-mode voltage range: ?V_S to +V_S ? 1.3 V
• Flexible power supplies: 3 V to 10 V

產品詳情

The ADA4945-1 is a low noise, low distortion, fully differential amplifier with a selectable power mode. It is an ideal choice for driving high resolution, high performance SAR and Σ-Δ analog-to-digital converters (ADCs) on 4 mA of quiescent current (full power mode) and can be selected to operate on 1.4 mA of quiescent current (low power mode) to scale the power consumption to the desired operation performance necessary for the ADC drive application. The adjustable level of theoutput common-mode voltage allows the ADA4945-1 to match the input common-mode voltage of multiple ADCs. The internal common-mode feedback loop provides exceptional output balance, as well as suppression of even order harmonic distortion products.

With the ADA4945-1, differential gain configurations are realized with a simple external feedback network of four resistors determining the closed-loop gain of the amplifier.The ADA4945-1 is fabricated using Analog Devices, Inc., proprietary, silicon germanium (SiGe), complementary bipolar process, enabling the device to achieve low levels of distortion with an input voltage noise of only 1.6 nV/√Hz (full power mode).

The low dc offset, dc offset drift, and excellent dynamic performance of the ADA4945-1 makes it well suited for a variety of data acquisition and signal processing applications.

The ADA4945-1 is available in a RoHS-complaint, 3 mm × 3 mm, 16-lead LFCSP. The ADA4945-1 is specified to operate over the?40°C to +125°C temperature range.

Applications

• Low power Σ-Δ, PulSAR^?/SAR ADC drivers
• Single-ended to differential conversion
• Differential buffers
• Medical imaging
• Industrial process controls
• Portable electronics

方框圖