Linear Technology: Micropower Op Amp Drives 8-Channel 18-Bit Simultaneous Sampling ADC

June 01, 2016 // By Guy Hoover
The op amps used to drive 18-bit analog-to-digital converters (ADCs) typically draw as much supply current as the ADC itself, often with a maximum offset spec that is well above that of the ADC. If multiple ADC channels are required, the power dissipation from these drivers quickly rises to unacceptable levels. If 18-bit precision is required (SNR, THD, VOS), but not high sampling rates, and the input signals are low frequency or DC, the simple buffer presented is capable of driving the LTC®2348-18 8-channel simultaneous sampling ADC. It also achieves performance equivalent to typical specs for SNR, THD and offset performance with very low power dissipation.
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