49.5.1 SERCOM in SPI Mode Timing Characteristics
| Symbol | Parameter | Conditions | Min. | Typ. | Max. | Units | |
|---|---|---|---|---|---|---|---|
| tSCK | SCK period | Host | Reception | 2*(tMIS+tCLIENT_OUT) (3) | - | - | ns |
| Host | Transmission | 2*(tMOV+tCLIENT_IN) (4) | - | - | |||
| tSCKW | SCK high/low width | Host | - | 0.5*tSCK | - | ||
| tSCKR | SCK rise time (2) | Host | - | 0.25*tSCK | - | ||
| tSCKF | SCK fall time (2) | Host | - | 0.25*tSCK | - | ||
| tMIS | MISO setup to SCK | Host. VDD>4.5V | 62.19 | - | - | ||
| Host. VDD>2.7V | 72.09 | - | - | ||||
| tMIH | MISO hold after SCK | Host. VDD>4.5V | 0 | - | - | ||
| Host. VDD>2.7V | 0 | - | - | ||||
| tMOV | MOSI output valid SCK | Host. VDD>4.5V | - | - | 18.1 | ||
| Host. VDD>2.7V | - | - | 24.6 | ||||
| tMOH | MOSI hold after SCK | Host. VDD>4.5V | 5.78 | - | - | ||
| Host. VDD>2.7V | 5.78 | - | - | ||||
| tSSCK | Client SCK Period | Client | Reception | 2*(tSIS+tHOST_OUT) (5) | - | - | |
| Client | Transmission | 2*(tSOV+tHOST_IN) (6) | - | - | |||
| tSSCKW | SCK high/low width | Client | - | 0.5*tSSCK | - | ||
| tSSCKR | SCK rise time (2) | Client | - | 0.25*tSSCK | - | ||
| tSSCKF | SCK fall time (2) | Client | - | 0.25*tSSCK | - | ns | |
| tSIS | MOSI setup to SCK | Client. VDD>4.5V | 14.77 | - | - | ||
| Client. VDD>2.7V | 15.27 | - | - | ||||
| tSIH | MOSI hold after SCK | Client. VDD>4.5V | 0 | - | - | ||
| Client. VDD>2.7V | 0 | - | - | ||||
| tSSS | SS setup to SCK | Client | PRELOADEN=1 | tSOSS+tEXT_MIS+2*tAPBC (8) (9) | - | - | |
| PRELOADEN=0 | tSOSS+tEXT_MIS (8) | - | - | ||||
| tSSH | SS hold after SCK | Client | 0.5*tSSCK | - | - | ||
| tSOV | MISO output valid SCK | Client. VDD>4.5V | - | - | 51.56 | ||
| Client. VDD>2.7V | - | - | 61.66 | ||||
| tSOH | MISO hold after SCK | Client. VDD>4.5V | 14.66 | - | - | ||
| Client. VDD>2.7V | 14.66 | - | - | ||||
| tSOSS | MISO setup after SS low | Client. VDD>4.5V | - | - | 47.25 | ||
| Client. VDD>2.7V | - | - | 56.95 | ||||
| tSOSH | MISO hold after SS high | Client. VDD>4.5V | 8.57 | - | - | ||
| Client. VDD>2.7V | 8.57 | - | - | ||||
Note:
- These values are based on simulation and are not covered by test limits in production.
- Refer to the section “I/O pin characteristics”.
- Where tCLIENT_OUT is the Client external device output response time, generally tEXT_SOV+tLINE_DELAY (7).
- Where tCLIENT_IN is the Client external device input constraint, generally tEXT_SIS+tLINE_DELAY (7).
- Where tHOST_OUT is the Host external device output response time, generally tEXT_MOV+tLINE_DELAY (7).
- Where tHOST_IN is the Host external device input constraint, generally tEXT_MIS+tLINE_DELAY (7).
- tLINE_DELAY is the transmission line time delay.
- tEXT_MIS is the input constraint for the Host external device.
- tAPBC is the APB period for SERCOM.
- When the integrity of
communication is required to maintain both transmission and reception, the
maximum SPI clock frequency must be the lower value of the reception or
transmission mode maximum frequency as shown in the following equations:
- Reception: tSCK = 2*(tMIS+tCLIENT_OUT)
- Transmission: tSCK = 2*(tMOV+tCLIENT_IN)