The OPA835 device provides excellent performance when driving high-performance delta-sigma (ΔΣ) and successive-approximation-register (SAR) ADCs in low-power audio and industrial applications.

To show achievable performance, the OPA835 device is tested as the drive amplifier for the ADS8326 device. The ADS8326 device is a 16-bit, micro power, SAR ADC with pseudodifferential inputs and sample rates up to
250 kSPS. The device offers excellent noise and distortion performance in a small 8-pin SOIC or VSSOP (MSOP) package. Low power and small size make the ADS8326 and OPA835 devices an ideal solution for portable and battery-operated systems, remote data-acquisition modules, simultaneous multichannel systems, and isolated data acquisition.

With the circuit shown in Figure 9-9 to test the performance, Figure 9-10 shows the spectral performance with a 10-kHz input frequency. The tabulated AC results are in Table 9-3.

Figure 9-9 OPA835 and ADS8326 Test Circuit

Figure 9-10 ADS8326 and OPA835 10-kHz FFT