Analog-to-digital converters from Texas Instruments

12th June 2008

ES Admin

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TI has introduced a pair of ±10V, 16-bit analog-to-digital converters (ADC) with excellent measurement repeatability and high resolution. Both the ADS8519 and ADS8513 combine a low-power successive approximation register (SAR) ADC with sample and hold, clock, reference and a serial data interface. The devices’ high integration enables design in industrial process control, DSP servo control, robotics, test equipment, portable data acquisition and medical instrumentation equipment.

The ADS8519 combines the standard ±10V industrial input range with new interface features and performance. The converter is specified at ±1.5 LSB maximum integral nonlinearity (INL), ±1 LSB maximum differential nonlinearity (DNL) at 16 bits and has a 250kHz sampling rate and flexible input ranges which can be configured for ±10V, ±5V, 0-4V, or 0-8V. It includes an on-chip 4.096V reference and a flexible voltage serial interface that can operate down to 1.65V I/O for glueless connectivity to any TI DSP processor. In addition, the device operates from a single 5V analog supply. The ADS8519 is able to deliver outstanding DC performance with only 0.05 percent full scale range (FSR) gain error and 2mV of bipolar zero error while still keeping power dissipation low at only 100mW for the full 250kHz sampling rate. This combination of features and performance makes it an attractive option for new ±10V industrial designs.

The ADS8513 is a drop-in upgrade to the ADS7813 and provides improved performance for current products without costly board redesigns. It offers excellent DC performance of ±2 LSB maximum INL and -1/+2 LSB maximum DNL. In addition, its exceptional AC performance, including a high signal-to-noise ratio of 89dB, low total harmonic distortion of 100dB and spurious-free dynamic range of 102dB, provides improved accuracy for high dynamic range signals. The device has full scale error drift of 0.2ppm/C and bipolar zero error drift of 2.5ppm/C. With its single 5V supply, the ADS8513 uses only 24mW at 40kSPS. It can be configured for several input voltage ranges including ±10V, ±5V, ±3.3V, 4V and 10V.

Both devices provide a SPI-compatible serial interface that allows data to be synchronized to an internal or external clock. In addition, they are specified over the industrial temperature range of -40C to 85C. The ADS8519 and ADS8513 are part of TI’s new ADS850x family of high-voltage SAR ADCs.