Overview
The AD7845KR, produced by Analog Devices Inc., is a 12-bit multiplying digital-to-analog converter (DAC) that features a full 4-quadrant multiplying capability and an integrated output amplifier. This device is fabricated using the LC2MOS process, which allows for the implementation of precision linear components and digital circuitry on the same chip. The AD7845KR is designed to provide high accuracy and flexibility, making it suitable for a variety of applications that require precise analog output control.
Key Specifications
| Parameter | Value | Unit | Comments |
|---|---|---|---|
| Resolution | 12 | Bits | |
| Relative Accuracy | ±1/2 LSB | ||
| Temperature Range | 0°C to +70°C | ||
| Output Voltage Range | ±10 V | Into a 2 kΩ load | |
| Settling Time | < 5 µs | To 0.01% FSR (1/2 LSB) | |
| Input Offset Voltage | Low due to laser trimming | ||
| Slew Rate | Typically 11 V/µs | ||
| Package Options | 24-lead DIP, 28-terminal LCC, PLCC, and 24-terminal SOIC | ||
| Digital Input Compatibility | TTL and 5 V CMOS |
Key Features
- Voltage Output Multiplying DAC: The AD7845KR features a full 4-quadrant multiplying capability with an integrated output amplifier.
- Matched Application Resistors: Three application resistors (RA, RB, RC) are provided for gain ranging and voltage offsetting.
- Space Saving: The integration of the output amplifier on-chip reduces chip count, and the device is available in compact packages such as 24-lead DIP, 28-terminal LCC, PLCC, and 24-terminal SOIC.
- Easy Microprocessor Interfacing: The 12 data inputs drive latches controlled by standard CS and WR signals, making it simple to interface with microprocessors.
- Low Power LC2MOS Process: Fabricated using the LC2MOS process, which allows for precision linear components and digital circuitry on the same chip.
Applications
- Automatic Test Equipment: The AD7845KR can be used in automated testing systems that require precise analog output control.
- Digital Attenuators: Suitable for applications where variable attenuation is necessary.
- Programmable Power Supplies: Can be used to control the output voltage in programmable power supply systems.
- Programmable Gain Amplifiers: Ideal for applications requiring adjustable gain settings.
- mA Converters: Useful in current-to-voltage conversion applications.
Q & A
- What is the resolution of the AD7845KR?
The AD7845KR has a resolution of 12 bits.
- What is the temperature range for the AD7845KR?
The AD7845KR operates over a temperature range of 0°C to +70°C.
- What is the output voltage range of the AD7845KR?
The AD7845KR can supply an output voltage range of ±10 V into a 2 kΩ load.
- How long does the AD7845KR take to settle?
The AD7845KR settles to 0.01% FSR (1/2 LSB) in less than 5 µs.
- What is the slew rate of the output amplifier in the AD7845KR?
The slew rate of the output amplifier is typically 11 V/µs.
- What types of digital inputs are compatible with the AD7845KR?
The AD7845KR is compatible with TTL and 5 V CMOS digital inputs.
- How does the AD7845KR save space in a design?
The integration of the output amplifier on-chip reduces the chip count, and the device is available in compact packages such as 24-lead DIP, 28-terminal LCC, PLCC, and 24-terminal SOIC.
- What are the application resistors used for in the AD7845KR?
The three application resistors (RA, RB, RC) are used for gain ranging and voltage offsetting.
- Can the AD7845KR be used in stand-alone operation?
Yes, the AD7845KR can be used in stand-alone operation by tying the CS and WR inputs to ground, making all latches transparent.
- What are some common applications of the AD7845KR?
The AD7845KR is commonly used in automatic test equipment, digital attenuators, programmable power supplies, programmable gain amplifiers, and mA converters.
