AD7845KNZ

Overview

The AD7845KNZ is a complete 12-bit CMOS multiplying digital-to-analog converter (MDAC) featuring an integrated output amplifier. Fabricated on the LC2MOS process, it supports full 4-quadrant multiplication with TTL and 5 V CMOS compatible digital inputs. The device includes three internal application resistors for gain ranging and offset adjustment. It operates within a temperature range of 0°C to +70°C and requires dual power supplies between ±14.25 V and ±15.75 V. Key electrical specifications include a maximum relative accuracy of -1/2 LSB at +25°C, a settling time of 5 µs to 0.01%, and a unity gain small signal bandwidth of 600 kHz.

Feature Summary

• Integrated 4-quadrant multiplying DAC with on-chip voltage output amplifier
• Three internal application resistors (RA, RB, RC) for gain scaling and offsetting
• TTL and 5 V CMOS compatible digital interface with latched inputs
• Guaranteed monotonic operation across the specified temperature range

Applications

• Automatic Test Equipment
• Programmable Gain Amplifiers
• Digital Attenuators
• Programmable Power Supplies
• Digital-to-4–20 mA Converters

Procurement Notes

Verify that the ordering suffix KNZ corresponds to the N-24 package variant with commercial temperature ratings. Confirm supply chain authenticity through authorized Analog Devices distributors or verified manufacturers. Check for RoHS compliance status as indicated in current product documentation. Ensure proper ESD handling procedures are followed during storage and assembly due to device sensitivity.

Selection Notes

Select the AD7845KNZ when a 12-bit resolution with integrated buffering is required for space-constrained designs. The K version offers improved relative accuracy (-1/2 LSB) compared to the J version. Ensure the system can provide the necessary ±15 V power rails. Consider the N-24 DIP package constraints if surface mount alternatives like SOIC or PLCC are preferred for automated assembly.

Part Context

The AD7845 series represents Analog Devices' first industry-standard 4-quadrant multiplying DAC with an on-chip amplifier. The KNZ designation identifies the specific accuracy grade and plastic DIP packaging within this family. This component bridges the gap between high-speed converters and precision instrumentation applications by combining digital control simplicity with analog performance.

Replacement Considerations

Direct pin-compatible replacements within the same package include the AD7845JN for standard accuracy or AD7845JPZ for surface mount LCC packages. Verify that substitute components maintain the required 12-bit resolution and 4-quadrant multiplication capabilities. Cross-reference thermal specifications to ensure compatibility with the intended operating environment.