SPRSP45C March 2020 – April 2024 TMS320F280021 , TMS320F280021-Q1 , TMS320F280023 , TMS320F280023-Q1 , TMS320F280023C , TMS320F280025 , TMS320F280025-Q1 , TMS320F280025C , TMS320F280025C-Q1
PRODUCTION DATA
The ADC input characteristics are given by Table 6-11 and Figure 6-42.
| DESCRIPTION | REFERENCE MODE | VALUE | |
|---|---|---|---|
| Cp | Parasitic input capacitance | All | See Table 6-12 |
| Ron | Sampling switch resistance | External Reference, 2.5-V Internal Reference | 500 Ω |
| 3.3-V Internal Reference | 860 Ω | ||
| Ch | Sampling capacitor | External Reference, 2.5-V Internal Reference | 12.5 pF |
| 3.3-V Internal Reference | 7.5 pF | ||
| Rs | Nominal source impedance | All | 50 Ω |
Figure 6-42 Input ModelThis input model should be used with actual signal source impedance to determine the acquisition window duration. For more information, see the following:
Table 6-12 lists the parasitic capacitance on each channel.
| ADC CHANNEL | Cp (pF) | |
|---|---|---|
| COMPARATOR DISABLED | COMPARATOR ENABLED | |
| ADCINA0/ADCINC15 | 3.3 | 15.8 |
| ADCINA1 | 2.4 | 4.9 |
| ADCINA2/ADCINC9 | 2.9 | 5.4 |
| ADCINA3/ADCINC5(1) | 71.4 | 73.9 |
| ADCINA4/ADCINC14 | 4.5 | 7 |
| ADCINA5/ADCINC2 | 2.7 | 5.2 |
| ADCINA6 | 2.6 | 5.1 |
| ADCINA7/ADCINC3 | 4.2 | 6.7 |
| ADCINA8/ADCINC11 | 4.5 | 7 |
| ADCINA9/ADCINC8 | 3.4 | 5.9 |
| ADCINA10/ADCINC10 | 2.9 | 5.4 |
| ADCINA11/ADCINC0 | 2.9 | 5.4 |
| ADCINA12/ADCINC1 | 4.7 | 7.2 |
| ADCINA14/ADCINC4 | 2.5 | 5 |
| ADCINA15/ADCINC7 | 3.3 | 5.8 |
| ADCINC6 | 2.9 | 5.4 |