K20P120M100SF2 Datasheet, PDF (56/66 Pages) Freescale Semiconductor, Inc – K20 Data Sheet

Peripheral operating requirements and behaviors
6.8.9 SDHC specifications
The following timing specs are defined at the chip I/O pin and must be translated
appropriately to arrive at timing specs/constraints for the physical interface.
Table 44. SDHC switching specifications
Num
SD1
SD2
SD3
SD4
SD5
SD6
SD7
SD8
Symbol
fpp
fpp
fpp
f_OD
t_WL
t_WH
t_TLH
t_THL
t_OD
t_ISU
t_IH
Description
Min.
Max.
Card input clock
Clock frequency (low speed)
0
400
Clock frequency (SD\SDIO full speed)
0
25
Clock frequency (MMC full speed)
0
20
Clock frequency (identification mode)
0
400
Clock low time
7
—
Clock high time
7
—
Clock rise time
Refer Table 3
Clock fall time
SDHC output / card inputs SDHC_CMD, SDHC_DAT (reference to SDHC_CLK)
SDHC output delay (output valid)
-5
6.5
SDHC input / card inputs SDHC_CMD, SDHC_DAT (reference to SDHC_CLK)
SDHC input setup time
5
—
SDHC input hold time
0
—
Unit
kHz
MHz
MHz
kHz
ns
ns
ns
ns
ns
ns
ns
SDHC_CLK
Output SDHC_CMD
Output SDHC_DAT[3:0]
Input SDHC_CMD
Input SDHC_DAT[3:0]
SD3
SD2
SD1
SD6
SD7
SD8
Figure 23. SDHC timing
K20 Data Sheet Data Sheet, Rev. 6.1, 08/2012.
56
Freescale Semiconductor, Inc.