SBASB22 December 2025 ADS9324
PRODUCTION DATA
Each analog input channel in the device presents an input resistance of 1MΩ on both AINnP and AINnM pins. The input resistance for each channel is independent of either the input signal frequency, the configured range of the ADC, or the oversampling mode. The primary advantage of such high-impedance inputs is the ease of driving the ADC inputs without requiring driving amplifiers with low output impedance. Bipolar, high-voltage power supplies are not required in the system because this ADC does not require any high-voltage, front-end drivers. In most applications, the signal sources or sensor outputs can be directly connected to the ADC input, thus significantly simplifying the design of the signal chain.
To maintain the dc accuracy of the system, matching the external source impedance on the AINnP input pin with an equivalent resistance on the AINnM pin is recommended (see Figure 7-3). This matching helps to cancel any additional offset error contributed by the external resistance.