Overview
The AD678KD is a 12-bit monolithic analog-to-digital converter (ADC) produced by Analog Devices Inc. This device is a complete, multipurpose ADC that integrates a sample-hold amplifier (SHA), a microprocessor-compatible bus interface, a voltage reference, and clock generation circuitry on a single chip. It is designed to minimize external component requirements, providing a fully specified sampling A/D function that is not achievable with discrete designs.
The AD678KD is fabricated using Analog Devices' BiMOS process, which combines low power CMOS logic with high precision, low noise bipolar circuits. This process includes laser-trimmed thin-film resistors to ensure high accuracy. The converter uses a recursive subranging algorithm with error correction and flash converter circuitry to achieve high speed and resolution.
Key Specifications
| Specification | Value |
|---|---|
| Resolution | 12 bits |
| Conversion Rate | 200 kSPS |
| Full Power Bandwidth | 1 MHz |
| Full Linear Bandwidth | 500 kHz |
| S/N+D Ratio | 72 dB (K, B, T Grades) |
| Input Range | 10 V (Unipolar or Bipolar) |
| Input Impedance | 10 MΩ |
| Supply Voltage | +5 V and ±12 V |
| Power Dissipation | 560 mW (typ) |
| Package | 28-lead Side-Brazed CerDIP |
| Temperature Range | 0°C to +70°C |
Key Features
- Complete integration of SHA, ADC, voltage reference, clock, and digital interface on a single chip.
- AC and DC characterized and specified (K, B, T Grades).
- Choice of digital interface formats: 16-bit bus in a single read operation or 8-bit bus in two read operations (8+4), with right or left justification.
- Data format is straight binary for unipolar mode and twos complement binary for bipolar mode.
- High input impedance allows direct connection to unbuffered sources without signal degradation.
- MIL-STD-883C Class B compliant versions available.
Applications
- Signal processing applications due to specified ac parameters such as S/N+D ratio, THD, and IMD.
- Measurement applications due to specified dc parameters.
- Military and industrial environments where high reliability and precision are required.
- Systems requiring high-speed and high-resolution analog-to-digital conversion.
Q & A
- What is the resolution of the AD678KD ADC?
The AD678KD has a resolution of 12 bits.
- What is the conversion rate of the AD678KD?
The AD678KD has a conversion rate of 200 kSPS.
- What is the full power bandwidth of the AD678KD?
The full power bandwidth of the AD678KD is 1 MHz.
- What is the input range of the AD678KD?
The input range of the AD678KD is 10 V, available in both unipolar and bipolar modes.
- What is the input impedance of the AD678KD?
The input impedance of the AD678KD is 10 MΩ.
- What are the supply voltages for the AD678KD?
The AD678KD operates from +5 V and ±12 V supplies.
- What is the typical power dissipation of the AD678KD?
The typical power dissipation of the AD678KD is 560 mW.
- In what package is the AD678KD available?
The AD678KD is available in a 28-lead Side-Brazed CerDIP package.
- What is the temperature range for the AD678KD?
The temperature range for the AD678KD is 0°C to +70°C.
- Is the AD678KD compliant with any military standards?
Yes, the AD678KD has versions that are compliant with MIL-STD-883C Class B.
