SBASAP6 February 2025 ADC3683-EP , ADC3683-SEP
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
The ADC voltage reference is selected using the REFBUF/CTRL pin. Even though there is an internal 100kΩ pull-up resistor to AVDD, the REFBUF/CTRL pin should be set to a voltage externally and not left floating. When using a voltage divider to set the REFBUF/CTRL voltage (R1 and R2 in Figure 7-49), resistor values < 5kΩ are used.
| REFBUF/CTRL VOLTAGE | VOLTAGE REFERENCE OPTION | CLOCKING OPTION |
|---|---|---|
| > 1.7V (Default) | External reference | Differential clock input |
| 1.2V (1.15-1.25V) | External 1.2V input on REFBUF/CTRL pin using internal gain buffer | Differential clock input |
| 0.5 - 0.7V | Internal reference | Differential clock input |
| < 0.1V | Internal reference | Single ended clock input |