AD7945ARSZ-B

Overview

The AD7945ARSZ-B is a 12-bit multiplying digital-to-analog converter (DAC) from Analog Devices, featuring a parallel interface and housed in a 20-lead SSOP package. It operates on a single supply voltage ranging from +3.0 V to +5.5 V. The device guarantees a relative accuracy of ±1 LSB maximum and differential nonlinearity of ±0.9 LSB maximum. Key electrical parameters include a typical power dissipation of 5 mW, an output leakage current of 10 nA max at +25°C, and a settling time of 5 µs to 0.01% in biased mode. It supports an industrial temperature range of -40°C to +85°C.

Feature Summary

• 12-bit resolution with guaranteed linearity specifications for single-supply operation
• Parallel data interface with active low Chip Select (CS) and Write (WR) inputs
• Low power consumption: typically 5 µA supply current and 5 mW power dissipation
• Current-output architecture with external reference input capability

Applications

• Battery-powered instrumentation systems
• Laptop computer peripheral interfaces
• Direct upgrades for legacy 754x series DAC designs in 5 V applications

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and temperature grade. The 'ARSZ' designation indicates a shrink small outline package (SSOP) with lead-free solder plating. Confirm availability status through authorized distributors as supply levels may vary by region.

Selection Notes

Select this component when a 12-bit parallel interface is required for single-supply applications. Ensure the system design accommodates the current-output nature of the DAC by including an appropriate operational amplifier for voltage conversion. Verify that the external reference voltage and load conditions align with the specified gain error and linearity performance metrics.

Part Context

This part belongs to the AD7943/AD7945/AD7948 family of fast 12-bit multiplying DACs. While the AD7943 utilizes a serial interface and the AD7948 uses an 8-bit byte interface, the AD7945 specifically provides a full 12-bit parallel data path. All variants share similar internal architectures and performance characteristics but differ in data loading mechanisms.

Replacement Considerations

The datasheet identifies the AD7945 as a direct replacement for industry-standard AD7545 devices in many applications, offering improved speed and lower power consumption. Designers upgrading from older parallel DACs should verify pin compatibility and timing requirements.