Overview
The AD7878LN, produced by Analog Devices Inc., is a high-performance, 12-bit analog-to-digital converter (ADC) designed with a versatile digital signal processing (DSP) interface. This component integrates a complete ADC function, including an on-chip track/hold circuit, an on-chip reference, and a 12-bit successive approximation register (SAR) ADC. The AD7878LN features an 8-word first-in, first-out (FIFO) memory and associated control logic, which significantly reduces the software overhead associated with servicing interrupts in DSP processors. Fabricated in Linear Compatible CMOS (LC2MOS) technology, this ADC combines precision bipolar circuits with low-power CMOS logic, making it suitable for a wide range of applications requiring high-speed and high-accuracy signal processing.
Key Specifications
| Parameter | Value | Units | Test Conditions/Comments |
|---|---|---|---|
| Number of Bits | 12 | ||
| Sampling Rate | 100 kHz | ||
| Number of Inputs | 1 | Single-ended input | |
| Data Interface | DSP | Compatible with DSP processors and high-speed microprocessors | |
| Configuration | S/H-ADC | Sample and Hold ADC | |
| Reference Type | Internal | ||
| Voltage - Supply, Analog | ±5 V | VDD = +5 V ± 5%, VSS = –5 V ± 5% | |
| Voltage - Supply, Digital | 5 V | VCC = +5 V ± 5% | |
| Operating Temperature | 0°C to +70°C | ||
| Package / Case | 28-pin plastic and hermetic dual-in-line package (DIP), leadless ceramic chip carrier (LCCC), or plastic leaded chip carrier (PLCC) | ||
| Signal-to-Noise Ratio (SNR) | 72 dB min | dB | VIN = 10 kHz Sine Wave, fSAMPLE = 100 kHz |
| Data Access Time | 41 ns max | ns | |
| Power Consumption | 60 mW typ | mW |
Key Features
- Complete A/D Function with DSP Interface: The AD7878LN provides a complete ADC function with an on-chip track/hold circuit, an on-chip reference, and a 12-bit SAR ADC, along with an 8-word FIFO memory to reduce software overhead.
- Dynamic Specifications for DSP Users: Fully specified and tested for AC parameters such as signal-to-noise ratio, harmonic distortion, and intermodulation distortion.
- Fast Microprocessor Interface: A fast data access time of 41 ns makes the AD7878LN compatible with modern 16-bit microprocessors and DSP processors.
- Low Power Consumption: Typical power consumption of 60 mW.
- Advanced Fabrication Technology: Fabricated in Linear Compatible CMOS (LC2MOS) technology, combining precision bipolar circuits with low-power CMOS logic.
Applications
- Digital Signal Processing: Ideal for applications requiring high-speed and high-accuracy signal processing.
- Speech Recognition and Synthesis: Suitable for speech processing applications due to its high dynamic performance.
- Spectrum Analysis: Used in spectrum analysis applications where high signal-to-noise ratio and low distortion are critical.
- High-Speed Modems: Compatible with high-speed modem applications requiring fast and accurate signal conversion.
- DSP Servo Control: Used in servo control systems where precise and rapid signal processing is necessary.
Q & A
- What is the resolution of the AD7878LN ADC?
The AD7878LN has a resolution of 12 bits.
- What is the sampling rate of the AD7878LN?
The sampling rate of the AD7878LN is up to 100 kHz.
- What type of input does the AD7878LN support?
The AD7878LN supports single-ended analog inputs.
- What is the data interface of the AD7878LN?
The AD7878LN has a DSP-compatible data interface.
- What is the operating temperature range of the AD7878LN?
The operating temperature range of the AD7878LN is from 0°C to +70°C.
- What is the signal-to-noise ratio (SNR) of the AD7878LN?
The SNR of the AD7878LN is typically 72 dB min.
- What is the data access time of the AD7878LN?
The data access time of the AD7878LN is 41 ns max.
- What is the power consumption of the AD7878LN?
The typical power consumption of the AD7878LN is 60 mW.
- In what package types is the AD7878LN available?
The AD7878LN is available in 28-pin plastic and hermetic dual-in-line package (DIP), leadless ceramic chip carrier (LCCC), or plastic leaded chip carrier (PLCC).
- What are some common applications of the AD7878LN?
The AD7878LN is commonly used in digital signal processing, speech recognition and synthesis, spectrum analysis, high-speed modems, and DSP servo control.
