ALD500RA-20SEL

Analog To Digital Converters (ADC) Overview

The ALD500RA-20SEL is a precision integrating analog processor from Advanced Linear Devices, designed for high-resolution analog-to-digital conversion. It operates on ±5V power supplies and features a dual-slope architecture suitable for 17-bit resolution applications. The device accepts differential analog inputs within a wide bipolar range of ±3.5V and includes an accurate on-chip voltage reference with a temperature coefficient as low as 20 ppm/°C. Key electrical characteristics include a typical input current of 2pA, low power dissipation of 6mW, and automatic zero offset compensation. It is housed in a 20-SOIC package and supports operation within the 0°C to 70°C temperature range.

Analog To Digital Converters (ADC) Feature Summary

• Dual-slope integrating architecture providing 17-bit resolution with linearity error as low as 0.01%.
• Differential analog input with high impedance (10^12 Ω) and wide bipolar range (±3.5V).
• On-chip precision voltage reference with guaranteed temperature coefficient of 20 ppm/°C.
• Automatic zero offset compensation and internal polarity detection for enhanced accuracy.

Analog To Digital Converters (ADC) Applications

• 4 1/2 to 5 1/2 digits plus sign measurements
• Precision analog signal processing
• High accuracy DC measurement functions
• Portable battery operated instruments

Analog To Digital Converters (ADC) Procurement Notes

Verify the specific suffix 'SEL' against the manufacturer's official documentation to confirm if it denotes a distinct packaging variant or testing standard compared to the standard 'SE' designation. Confirm that the 20-SOIC package dimensions match the required PCB footprint. Ensure the external digital controller interface logic levels are compatible with CMOS families as specified in the datasheet.

Analog To Digital Converters (ADC) Selection Notes

Select this component for applications requiring high noise immunity and inherent integration of input signals. The dual-slope design ensures accuracy independent of absolute resistor and capacitor values, relying instead on their ratio stability during the conversion cycle. Consider the trade-off between conversion speed and resolution, as higher resolution requires longer integration times. Ensure the external clock frequency aligns with the recommended crystal oscillator options for optimal performance.

Analog To Digital Converters (ADC) Part Context

The ALD500RA-20SEL belongs to the ALD500R series of precision integrating analog processors. This family includes variants such as ALD500R (16-bit), ALD500RA (17-bit), and ALD500RAU (18-bit), differentiated primarily by resolution and linearity specifications. The RA variant specifically targets 17-bit applications with a 20 ppm/°C temperature coefficient for the internal reference, offering a balance between precision and cost-effectiveness for industrial instrumentation.

Analog To Digital Converters (ADC) Replacement Considerations

Direct pin-compatible replacements within the same family include ALD500RA-20SE (standard SOIC) or ALD500RA-20QE (QSOP package). For higher resolution needs, the ALD500RAU-20SE offers 18-bit performance. Lower resolution requirements may be met by the ALD500R-20SE. Verify that any substitute maintains the same ±5V supply requirement and differential input configuration.