There are a number of advantages for utilizing an external analog to digital converter (ADC) in a project’s design. The internal ADC of the PIC18F series is limited to 10-bit resolution, while much higher resolution ADCs are available.
In addition, high-speed multi-channel conversion is possible utilizing multiple external ADCs and multi-channel ADCs. The MAX1241 is a 12-bit single-channel ADC that has a “7.5µs successive-approximation ADC, a fast track/hold (1.5µs), an on-chip clock, and a high-speed, 3-wire serial interface.” All of these contribute to a great compact analog-to-digital converter, which can be utilized in a number of situations where high-speed sampling (73ksps) is required.
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