| Pin Group | Pins | Exclusive Note | | :--- | :--- | :--- | | Analog Inputs | AIN0–AIN3 | Differential pairs are (AIN0, AIN1) and (AIN2, AIN3). Do cross-pair them. | | Reference | REFP, REFN | Requires a 10µF low-ESR cap within 2mm of REFP. Common mistake: using 1µF causes 15% gain error. | | Digital I/O | GPIO0–GPIO5 | GPIO2 is open-drain only in the E revision. Check your date code. | | Power | VDD, AVDD, VSS | Exclusive: Power AVDD 50ms before VDD to avoid latch-up. Not in the public summary. |
| Register | Bit | Function | Exclusive Note | | :--- | :--- | :--- | :--- | | 0x0A | 4 | ADC dither enable | Increases ENOB from 20.1 to 21.3 bits at the cost of 5% more current. | | 0x0F | 7 | Fast settling mode | Reduces settling time to 40 µs but increases noise floor. Use only for DC measurements. | | 0x12 | 0:2 | Output driver strength | Default is '000' (weak). Set to '101' for driving long traces >10 cm. | | 0x1C | 3 | Internal reference bypass | Use only if you supply external REF. Prevents contention. | my 9892 datasheet exclusive