AD7837BN

Overview

The AD7837BN is a complete, dual 12-bit multiplying digital-to-analog converter (MDAC) manufactured by Analog Devices. It utilizes LC2MOS technology and features an R-2R resistor structure with integrated output amplifiers. The device operates on dual power supplies ranging from ±14.25 V to ±15.75 V. Key static performance metrics include a relative accuracy of ±1/2 LSB maximum and a differential nonlinearity of ±1 LSB maximum. The voltage output settling time is typically 3 µs to within ±1/2 LSB. The component is housed in a 24-lead Plastic DIP (N-24) package and supports an industrial operating temperature range of –40 °C to +85 °C.

Feature Summary

• Dual 12-bit Multiplying DACs with integrated buffered voltage outputs
• High precision: ±1/2 LSB relative accuracy and ±1 LSB DNL
• Fast settling time of 3 µs typical (5 µs max)
• Parallel input loading structure for microprocessor interfacing
• LC2MOS architecture with R-2R segmented current steering

Applications

• Automatic Test Equipment
• Function Generation and Waveform Reconstruction
• Programmable Power Supplies
• Synchro Applications
• Programmable Gain Amplifiers (PGA)

Procurement Notes

Verify the specific suffix 'BN' corresponds to the B version accuracy (±1/2 LSB) and N package option (Plastic DIP). Confirm that the required relative accuracy meets the ±1/2 LSB specification, as the A version offers ±1 LSB. Ensure supply voltages are maintained within the specified ±14.25 V to ±15.75 V range for guaranteed performance. Check for ESD sensitivity precautions during handling.

Selection Notes

Select the AD7837BN when a dual-channel 12-bit MDAC with high linearity (±1/2 LSB) is required. This model is suitable for systems using 8-bit wide data buses due to its parallel loading structure involving separate MSB and LSB latches. Choose this over the AD7847 if independent chip select lines for each channel are not needed, as the AD7837 uses a common CS line. Ensure the application can accommodate the external feedback resistor connection required for the AD7837, unlike the internally connected feedback of the AD7847.

Part Context

The AD7837 is part of the AD7837/AD7847 family of LC2MOS complete dual 12-bit MDACs. It shares the same core functionality and pinout as the AD7847 but differs in interface logic; the AD7837 uses a parallel loading structure optimized for 8-bit microprocessors, while the AD7847 uses a serial-compatible parallel interface. The 'B' designation indicates tighter linearity specifications compared to the 'A' version, and 'N' denotes the plastic DIP package.

Replacement Considerations

The AD7837ANZ is a direct replacement if ±1 LSB accuracy is acceptable. The AD7837BRZ offers the same B-version accuracy in a surface-mount SOIC package. For applications requiring independent channel selection, the AD7847BN provides equivalent performance with different control logic.