Overview
The AD7849AR is a 14-bit/16-bit serial input multiplying digital-to-analog converter (DAC) produced by Analog Devices Inc. This component is designed to ensure excellent differential linearity performance and monotonicity, making it suitable for a variety of precision control applications. The AD7849AR features a robust architecture that includes an input serial-to-parallel shift register, a DAC latch, and an output stage capable of driving a 2 kΩ load in parallel with 200 pF. Despite being marked as obsolete, it remains a significant component in legacy systems and specific industrial applications.
Key Specifications
| Parameter | Value | Unit | Test Conditions/Comments |
|---|---|---|---|
| Number of Bits | 14/16 | - | - |
| Resolution | 14-bit/16-bit | - | - |
| Input High Voltage (VINH) | 2.4 | V | Min |
| Input Low Voltage (VINL) | 0.8 | V | Max |
| Input Current (IINH) | ±10 | μA | Max |
| Input Capacitance (CIN) | 10 | pF | Max |
| Output Low Voltage (VOL) | 0.4 | V | Max at ISINK = 1.6 mA |
| Output High Voltage (VOH) | 4.0 | V | Min at ISOURCE = 400 μA |
| Supply Voltage (VDD) | 14.25/15.75 | V | Min/Max |
| Operating Temperature | -40°C to 85°C | - | - |
| Settling Time | 10 μs | - | Typical |
| Data Interface | SPI | - | - |
| Package/Case | 20-SOIC | - | - |
Key Features
- High Resolution: The AD7849AR offers 14-bit or 16-bit resolution, ensuring high precision in digital-to-analog conversion.
- Serial Input: It features a serial input interface, compatible with SPI protocols, allowing for easy integration into microcontroller-based systems.
- Output Stage: The output stage can drive a 2 kΩ load in parallel with 200 pF and includes feedback and offset resistors for gain and offset adjustments.
- Power-Up/Down Stability: The component has a special feature to clamp the output to 0 V during power-up and power-down sequences, ensuring stability in control applications.
- External Reference: It supports an external voltage reference, allowing for flexible voltage output ranges.
- Low INL/DNL: The component has low integral nonlinearity (INL) and differential nonlinearity (DNL), ensuring accurate conversions.
Applications
The AD7849AR is suitable for various applications requiring precise digital-to-analog conversion, including:
- Industrial Control Systems: For controlling actuators and other devices in industrial environments.
- Medical Devices: In medical equipment where precise analog outputs are necessary.
- Aerospace and Defense: For applications requiring high reliability and precision.
- Automotive Systems: In automotive control systems where accurate analog signals are crucial.
- Test and Measurement Equipment: For generating precise analog signals in test and measurement applications.
Q & A
- What is the resolution of the AD7849AR?
The AD7849AR has a resolution of 14 bits or 16 bits.
- What type of interface does the AD7849AR use?
The AD7849AR uses a serial input interface compatible with SPI protocols.
- What is the typical settling time of the AD7849AR?
The typical settling time is 10 μs.
- What is the operating temperature range of the AD7849AR?
The operating temperature range is -40°C to 85°C.
- Can the AD7849AR drive a load directly?
Yes, it can drive a 2 kΩ load in parallel with 200 pF.
- How does the AD7849AR handle power-up and power-down sequences?
The component clamps the output to 0 V during power-up and power-down sequences to ensure stability.
- Is the AD7849AR still in production?
No, the AD7849AR is marked as obsolete and is no longer manufactured.
- What package type is the AD7849AR available in?
The AD7849AR is available in a 20-SOIC package.
- What are the supply voltage requirements for the AD7849AR?
The supply voltage requirements are 14.25V to 15.75V for the analog supply and 5V for the digital supply.
- Does the AD7849AR support external voltage references?
Yes, it supports external voltage references.
