AD7840KNZ

Overview

The AD7840KNZ is a complete 14-bit voltage output digital-to-analog converter (DAC) fabricated in LC2MOS technology. It integrates a 14-bit DAC, a 3 V buried Zener reference, an output amplifier, and high-speed control logic. The device supports both parallel and serial interfaces, enabling direct connection to high-speed DSPs like the ADSP-2100 and TMS32010. Key electrical specifications include a minimum signal-to-noise ratio of 80 dB, a typical power dissipation of 70 mW, and operation from ±5 V supplies. The analog output provides a bipolar range of ±3 V with a settling time of typically 2 μs.

Feature Summary

• Complete 14-bit voltage output DAC with integrated 3 V reference and output buffer
• Dual interface capability: Parallel mode with 21 ns setup time and Serial mode up to 6 MHz clock
• High dynamic performance: 80 dB SNR and -80 dB THD at 1 kHz
• Low power consumption: Typically 70 mW at ±5 V supplies

Applications

• Direct interfacing with high-speed DSP processors such as ADSP-2100 and TMS320 series
• Speech synthesis systems requiring fast data update rates
• Servo control applications needing precise bipolar voltage generation
• High-speed modem signal generation

Procurement Notes

Verify the ordering suffix 'KNZ' against the manufacturer's current documentation. The provided datasheet lists 'AD7840KN' in the plastic DIP package but does not explicitly define the 'Z' suffix or confirm its RoHS compliance status within the text. Ensure the specific variant matches the required environmental standards and package type before procurement.

Selection Notes

Select the AD7840KNZ for applications requiring 14-bit resolution with a guaranteed 80 dB SNR and ±1 LSB maximum integral nonlinearity. Choose this part over lower grades if strict dynamic performance limits are necessary. Verify that the system can accommodate the ±5 V supply requirement and the ±3 V output swing relative to the available reference voltage.

Part Context

The AD7840 belongs to Analog Devices' family of complete 14-bit DACs utilizing LC2MOS technology. This process combines precision bipolar circuits with low-power CMOS logic. The device is designed to replace older microprocessor-compatible DACs by offering integrated buffering and reference capabilities, reducing external component count in signal processing designs.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided source material.