SPRUIW9C October 2021 – March 2024 TMS320F280033 , TMS320F280034 , TMS320F280034-Q1 , TMS320F280036-Q1 , TMS320F280036C-Q1 , TMS320F280037 , TMS320F280037-Q1 , TMS320F280037C , TMS320F280037C-Q1 , TMS320F280038-Q1 , TMS320F280038C-Q1 , TMS320F280039 , TMS320F280039-Q1 , TMS320F280039C , TMS320F280039C-Q1
The opens/shorts detection circuit (OSDETECT) can be used to detect pin faults in the system. The circuit connects to the ADC input after the channel select multiplexer but before the S+H circuit as shown in Figure 16-10.
The circuit can be operated by writing a value to the DETECTCFG field in the ADCOSDETECT register. This causes the circuit to source a voltage onto the input during the S+H phase of any conversion. The voltage and drive strength of the OSDETECT circuit for different DETECTCFG settings is given in Table 16-7.
ADCOSDETECT. DETECTCFG | Source Voltage | S4 | S3 | S2 | S1 | Drive Impedance |
---|---|---|---|---|---|---|
0 | Off | Open | Open | Open | Open | Open |
1 | Zero Scale | Closed | Open | Open | Closed | 5K || 7K |
2 | Full Scale | Open | Closed | Closed | Open | 5K || 7K |
3 | 5/12 VDDA | Open | Closed | Open | Closed | 5K || 7K |
4 | 7/12 VDDA | Closed | Open | Closed | Open | 5K || 7K |
5 | Zero Scale | Open | Open | Open | Closed | 5K |
6 | Full Scale | Open | Open | Closed | Open | 5K |
7 | Zero Scale | Closed | Open | Open | Open | 7K |