DS8007A Datasheet, PDF (9/41 Pages) Maxim Integrated Products – Multiprotocol Dual Smart Card Interface

Multiprotocol Dual Smart Card Interface
AC ELECTRICAL SPECIFICATIONS—TIMING PARAMETERS FOR CONSECUTIVE
READ/WRITE TO URR/UTR/TOC
(V_DD = 3.3V, V_DDA = 3.3V, T_A = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP MAX UNITS
SEE FIGURE 3
RD Pulse Width
t_W(RD)
10
ns
RD Low to Bit CRED = 1
t_RD(URR)
t_W(RD) +
2t_CY(CLK)
t_W(RD) +
3t_CY(CLK)
ns
Set Time Bit FE
t_SB(FE)
10.5
ETU
Set Time Bit RBF
t_SB(RBF)
10.5
ETU
SEE FIGURE 4
WR/CS Pulse Width
t_W(WR) (Note 4)
10
ns
WR/CS Low to I/O Low
t_WR(UTR)
t_W(WR) +
2t_CY(CLK)
t_W(WR) +
ns
3t_CY(CLK)
SEE FIGURE 5
WR/CS Pulse Width
WR/CS High to Bit CRED = 1
t_W(WR)
t_W(TOC)
(Notes 4 and 5)
10
1 / PSC
ns
2 / PSC ETU
Note 4: Depends on the leading edge of WR or CS (whichever is deasserted first). Reference this specification to the rising edge
of CS/WR instead of the falling edge.
Note 5: PSC is the programmed prescaler value (31 or 32).
I/Ox
RBF BIT
FE BIT
t_SB(FE)
t_SB(RBF)
INT
RD
CRED BIT
t_W(RD)
t_RD(URR)
Figure 3. Timing Between Two Read Operations in Register URR
_______________________________________________________________________________________ 9