AD7943ARSZ-B

Overview

The AD7943ARSZ-B is a 12-bit multiplying digital-to-analog converter (DAC) from Analog Devices, featuring a serial interface. It operates in Normal Mode with a +5 V supply or Biased Mode with +3.3 V to +5 V supplies. The device guarantees ±0.5 LSB relative accuracy and differential nonlinearity (DNL). Key electrical parameters include a typical power dissipation of 5 mW, a settling time of 600 ns to 0.01%, and a glitch impulse of 60 nV-s. It utilizes an R-2R segmented architecture and requires an external reference voltage.

Feature Summary

• 12-bit resolution with guaranteed ±0.5 LSB INL and DNL linearity
• Serial interface with 40 ns minimum strobe pulsewidth
• Low power consumption: typically 5 μA supply current (5 mW)
• Fast settling time of 600 ns to 0.01% full-scale range

Applications

• Battery-powered instrumentation
• Laptop computers
• Upgrades for AD754x series DACs in 5 V designs

Procurement Notes

Verify the ordering suffix 'B' indicates Biased Mode operation suitable for single-supply applications. Confirm the package type corresponds to RS-20 (SSOP). Ensure the required temperature range matches the industrial grade (-40°C to +85°C). Cross-reference the specific revision level with the manufacturer's datasheet to confirm pinout and electrical specifications.

Selection Notes

Select this component when a serial interface is required for space-constrained designs. Choose the AD7943 over parallel variants (AD7945/AD7948) if minimizing digital I/O pins is critical. Ensure the application supports the Biased Mode configuration if operating from a single low-voltage supply, as this variant biases outputs to 1.23 V.

Part Context

The AD7943 is part of the AD7943/AD7945/AD7948 family of fast 12-bit multiplying DACs. While the AD7945 uses a 12-bit parallel interface and the AD7948 uses an 8-bit byte interface, the AD7943 specifically implements a serial input structure. All three share identical core DAC performance characteristics and architectural features.

Replacement Considerations

The AD7943AN-B is a direct functional replacement within the same package family but uses a Plastic DIP (N-16) instead of SSOP. For legacy system upgrades, the AD7543 serves as the industry-standard predecessor, though the AD7943 offers superior speed and lower power consumption.

FAQ

What is the difference between Normal Mode and Biased Mode?

Normal Mode operates from a single +5 V supply with outputs referenced to ground. Biased Mode (indicated by the '-B' suffix) operates from +3.3 V to +5 V supplies and biases the IOUT1/IOUT2 terminals to 1.23 V for single-supply operation.

How is the serial data clocked into the AD7943?

Data is clocked into the input shift register on the rising edge of STB1, falling edge of STB3, or rising edge of STB2/STB4, depending on the specific strobe signal enabled. Four strobe inputs allow flexible timing control.

What is the maximum differential nonlinearity specified?

The AD7943 guarantees a Differential Nonlinearity (DNL) of ±0.5 LSB maximum across the specified temperature range.