BCM4339 Preliminary Data Sheet
SDIO/gSPI Timing
SDIO Bus Timing Specifications in SDR Modes
Clock Timing
Figure 45: SDIO Clock Timing (SDR Modes)
tCLK
SDIO_CLK
tCR
tCF
tCR
Table 54: SDIO Bus Clock Timing Parameters (SDR Modes)
Parameter
Symbol
Minimum
Maximum
Unit
Comments
–
tCLK
40
20
10
4.8
–
–
ns
ns
ns
ns
ns
SDR12 mode
SDR25 mode
SDR50 mode
SDR104 mode
–
–
–
–
tCR, tCF
0.2 × tCLK
tCR, tCF < 2.00 ns (max.) @100 MHz,
CCARD = 10 pF
t
C
CR, tCF < 0.96 ns (max.) @208 MHz,
CARD = 10 pF
Clock duty
cycle
–
30
70
%
–
Broadcom®
November 17, 2014 • 4339-DS106-R
Page 162