Datasheet

Evaluates: MAX4948
SD Sockets
The two on-board SD card sockets accommodate both
a standard SD memory card and a thin SD memory
card. The pinout for each SD socket is listed in Table 3.
Header J1
The 24-pin, dual-row header (J1) connects the P1 and
P2 SD sockets to the normally open (NO) and normally
closed (NC) terminals. The P1 socket is connected
through header J1 to the switches’ NO terminals
(NO1–NO6). The P2 socket is connected through head-
er J1 to the switches’ NC terminals (NC1–NC6). See
Table 4 for a pinout of header J1.
Header J2
The 16-pin, dual-row header (J2) connects the
COM1–COM6 terminals to the PCB plug (P3). In addi-
tion, the VDD supply voltage from the SD card reader/SD
card port is routed through J2 to each VCC pin of socket
P1 and P2. See Table 5 for a pin-to-pin association
between J2, the PCB plug, and the switches’
COM terminals.
SD PCB Plug
The MAX4948 EV kit was designed on a customized
PCB to allow for actual application evaluation. The SD
plug (P3) is an extension of the PCB and can be insert-
ed into a standard SD card socket. This design allows
two SD memory cards to be switched into a single SD
card socket. See Table 6 for the SD plug’s net associa-
tions. The pinout and dimensions of the SD plug are
shown in Figures 2 and 3.
MAX4948 Evaluation Kit
4 _______________________________________________________________________________________
Table 3. P1 and P2 Pinout
SD P1 PIN P2 PIN
DAT1 8 8
DAT0 7 7
GND 6 6
CLK 5 5
VCC 4* 4**
GND 3 3
CMD 2 2
DAT3 1 1
DAT2 9 9
* Shunted to VDD at header J2 (J2-7 to J2-8).
** Shunted to VDD at header J2 (J2-9 to J2-10).
Table 5. J2 Pinout
PIN
ASSOCIATION
J2 PIN
(ODD)
J2 PIN
(EVEN)
P3 PLUG
PIN
COM6 1 2 P3-8
COM5 3 4 P3-7
COM4 5 6 P3-5
P1-4 7* 8** P3-4
P2-4 9* 10** P3-4
COM3 11 12 P3-2
COM2 13 14 P3-1
COM1 15 16 P3-9
* VCC: SD memory card supply voltage.
** VDD: Host-interface supply voltage.
Table 4. J1 Pinout
NET
J1 PIN
(ODD)
J1 PIN
(EVEN)
MAX4948 (U1)
PIN
P1DAT1 1 2 NO6
P2DAT1 3 4 NC6
P1DAT0 5 6 NO5
P2DAT0 7 8 NC5
P1CLK 9 10 NO4
P2CLK 11 12 NC4
P1CMD 13 14 NO3
P2CMD 15 16 NC3
P2DAT3 17 18 NC2
P1DAT3 19 20 NO2
P2DAT2 21 22 NC1
P1DAT2 23 24 NO1
Table 6. SD Plug Pinout
NET NAME P3 PIN SD
SD8 8 DAT1
SD7 7 DAT0
GND 6 GND
SD5 5 CLK
VDD 4 VDD
GND 3 GND
SD2 2 CMD
SD1 1 DAT3
SD9 9 DAT2