- Voltage output settling time (from 1/4 scale to 3/4 scale to within 0.5 LSB, 14-bit) is 18us
- I2C maximum clock speed is 400kHz
The maximum I2C clock rate is 400kHz, and it takes 20 bits of I2C transmissions (4 bytes +4 ACK/NACK bits) to program a new DAC value. Thus, the I2C interface limits the update speed to 400kHz/20 = 20kHz. This is more of a limiting factor.
Based on these constraints, the analog circuitry should settle faster than the digital interface circuitry can update it, and the guaranteed sampling rate is limited by the digital communication speed placed on the host and the MAX5217.