AD7834BR

Overview

The AD7834BR is a monolithic quad 14-bit digital-to-analog converter (DAC) from Analog Devices, utilizing LC2MOS technology. It integrates four independent voltage-output DACs within a single 28-lead SOIC package. The device features serial data loading via DIN, SCLK, and FSYNC pins, supporting up to 32 individually addressable units through dedicated PA0–PA4 pins. It provides a maximum output voltage span of 14 V with a range of ±8.192 V. Key specifications include a typical settling time of 10 µs, relative accuracy of ±1 LSB for the B grade, and power-on reset functionality that holds outputs near the Device Sense Ground (DSG) potential during supply stabilization.

Feature Summary

• Quad 14-bit resolution with R-2R architecture in a 28-lead SOIC package
• Serial interface with user-assigned addressing for multi-device daisy-chaining
• Asynchronous CLR input allows forcing all outputs to a user-defined DSG voltage
• Power-on reset circuitry maintains outputs within ±2 V of DSG until supplies stabilize

Applications

• Process control systems requiring multi-channel analog generation
• Automatic test equipment needing precise voltage references
• General-purpose instrumentation with serial bus integration

Procurement Notes

Verify component authenticity as the AD7834 series has reached end-of-life status. Confirm the 'B' suffix indicates the specific accuracy grade (±1 LSB relative accuracy) required for the design. Check for RoHS compliance if applicable to current manufacturing batches, noting that original production may have been Pb-free while later stock or substitutes vary. Ensure the 28-SOIC footprint matches the PCB layout constraints.

Selection Notes

Select the AD7834BR when serial communication is preferred over parallel interfaces to reduce pin count. The B grade offers tighter relative accuracy (±1 LSB) compared to the A grade (±2 LSB). Ensure the application can support the required dual analog supplies (±15 V or ±12 V) and 5 V logic supply. Verify that the 10 µs settling time meets the system's update rate requirements.

Part Context

The AD7834 belongs to the AD7834/AD7835 family of LC2MOS DACs. While the AD7835 utilizes parallel loading, the AD7834 specifically implements serial input logic. The 'BR' designation identifies the B-grade accuracy version housed in the 28-lead Small Outline Integrated Circuit (SOIC) package. This part is distinct from the AD7837 (12-bit) and AD7840 (single channel) variants.

Replacement Considerations

Public documentation confirms the AD7834ARZ as a direct substitute. Verify that the replacement matches the B-grade accuracy specifications if tight linearity is critical. Check for package compatibility between the original SOIC and any alternative packaging options provided by distributors.