Special Purpose Analog-to-Digital Converters (ADCs) and Digital-to-Analog Converters (DACs) are integrated circuits designed for specific data acquisition tasks requiring tailored performance characteristics. These ICs enable precise signal conversion in specialized applications where standard converters cannot meet unique requirements such as ultra-high speed, extreme accuracy, isolation, or environmental robustness. They are critical in advanced industrial control systems, medical instrumentation, aerospace electronics, and high-frequency communication systems.
| Type | Functional Characteristics | Application Examples |
|---|---|---|
| High-Speed ADCs | Sampling rates >1 GSPS, low latency, wide bandwidth | Radar systems, 5G transceivers |
| High-Precision ADCs | 24-bit resolution, 2ppm linearity, low noise | Medical imaging, precision test equipment |
| Isolated ADCs | Galvanic isolation up to 5kVRMS, CMTI >100kV/ s | Industrial motor drives, grid-tied inverters |
| Multi-Channel DACs | Synchronized channels, crosstalk < -100dB | Automotive LiDAR beam steering |
| Radiation-Hardened ADCs | Latch-up immunity, TID tolerance >100krad | Satellite payloads, nuclear instrumentation |
Typical architecture includes:
| Parameter | Description | Importance |
|---|---|---|
| Effective Number of Bits (ENOB) | Actual resolution considering noise/distortion | System accuracy benchmark |
| Signal-to-Noise and Distortion (SINAD) | Dynamic range measurement | Determines minimum detectable signal |
| Integral Nonlinearity (INL) | Deviation from ideal transfer function | Essential for precision measurements |
| Power Supply Rejection Ratio (PSRR) | Noise immunity from power rails | System stability in varying conditions |
| Operating Temperature Range | -55 C to +150 C for automotive/military grades | Environmental reliability |
| Manufacturer | Product Series | Key Specifications |
|---|---|---|
| Analog Devices | AD7124-8 | 24-bit - ADC, 0.001% linearity, TUE <0.1% |
| TI Semiconductor | ADS54J60 | 16-bit, 1GSPS ADC with 74dB SNR |
| Maxim Integrated | MAX11156 | 16-channel, 18-bit SAR ADC, 0.1LSB INL |
| STMicroelectronics | LTC2380-24 | 24-bit, 2Msps ADC with 2ppm INL |
| NXP Semiconductors | MC12DX1080 | 8-channel DAC with 12.5ps jitter for LiDAR |
Key selection criteria:
Emerging trends include: