AD7845KP

Overview

The AD7845KP is a 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 guaranteed monotonicity across its operating temperature range of 0°C to +70°C. The device achieves a relative accuracy of -1/2 LSB at +25°C and includes three on-chip application resistors for gain ranging and offset adjustment. It utilizes parallel data inputs compatible with TTL and 5V CMOS logic, housed in a 28-terminal Plastic Leaded Chip Carrier (PLCC) package.

Feature Summary

• Integrated Output Amplifier: Provides voltage output capability with internal compensation and laser-trimmed low input offset voltage.
• On-Chip Application Resistors: Includes RA, RB, and RC for simplified gain ranging and offset adjustments without external components.
• 4-Quadrant Multiplication: Supports AC or DC reference signals for precise multiplying DAC applications.
• Guaranteed Monotonicity: Ensures stable operation over the full commercial temperature range (TMIN to TMAX).

Applications

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

Procurement Notes

Verify the specific suffix 'KP' corresponds to the 28-lead PLCC package and commercial temperature grade during sourcing. Confirm RoHS compliance status as older manufacturing runs may vary. Ensure ESD precautions are observed due to the sensitivity of the CMOS input structure. Cross-reference the ordering guide to confirm availability of the P-28A package option.

Selection Notes

Select the AD7845KP when a compact surface-mount solution is required for 12-bit multiplying DAC functions. The PLCC package offers space savings compared to DIP options while maintaining pin compatibility with other variants. Consider the on-chip resistors if gain scaling is needed to reduce external component count. Verify that the 0°C to +70°C temperature range meets system environmental requirements.

Part Context

The AD7845 series represents Analog Devices' first 4-quadrant multiplying DAC with an on-chip amplifier. The 'K' suffix denotes a tighter relative accuracy specification (-1/2 LSB max at +25°C) compared to the standard 'J' version (-1 LSB). The 'P' suffix identifies the 28-terminal Plastic Leaded Chip Carrier package. This variant belongs to the commercial temperature grade family alongside the KN and JP models.

Replacement Considerations

The AD7845JP serves as a direct functional substitute within the same package type but offers lower accuracy specifications (-1 LSB vs -1/2 LSB). For through-hole implementations, the AD7845KN provides equivalent electrical performance in a 24-lead DIP package.