MAX14502AETL+T Maxim Integrated Products, MAX14502AETL+T Datasheet - Page 20

• Manufacturer Part Number: MAX14502AETL+T
• Description: IC CARD READER USB-SD 40-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX14502AETL+T

• Applications: USB
• Interface: I²C
• Voltage - Supply: 1.8 V ~ 3.3 V
• Package / Case: 40-TQFN Exposed Pad
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Hi-Speed USB-to-SD Card
Readers with Bypass
Figure 7. Default Startup (Pass Thru Mode)
In the default Pass Thru mode, the MAX14500–
MAX14503 are transparent and the existing host func-
tions (access to SD cards and USB) are preserved
(Figure 7). The host µP reads and writes data to the SD
card from the SD port, and can communicate to a PC
through its existing full-speed USB port. All of the fea-
tures of the original chipset are intact. The MAX14500–
MAX14503 sleep when in Pass Thru mode (WAKEUP =
0), when the MODE input is low, or when the MODE bits
[2:1] in control register (0x00) are set to Card Reader
mode, not active. In Sleep mode, the internal microcon-
troller is turned off and current consumption is mini-
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CONNECTOR
USB
SLOT2
SLOT1
Default Power-Up (Pass Thru Mode)
SD
SD
D+
D-
4
4
CCLK2
CCMD2
CDAT2_[3:0]
CCRD_PRST
CCLK1
CCMD1
CDAT1_[3:0]
CD+
CD-
TRANSCEIVER
SD CARD INTERFACE
USB
CARD READER
USB HS
USB SWITCHES
SD PORT 2 SWITCHES
MAX14500–
MAX14503
mized. The settings for SD port switches for card 1 and
card 2 are controlled by SD port switch bits [4:3] in the
control register.
In Card Reader mode, the PC communicates with the
SD card through USB with an internal Hi-Speed SD
card reader, bypassing the host µP. Figure 8 shows
card reader mode with SD card 1 connected to the PC
with the internal card reader. The 40-pin TQFN can
connect to a single SD card in Card Reader mode. With
the 56-bump WLP operating under I
SD card can be selected for Card Reader mode.
SD PORT 1 SWITCHES
HDAT2_[3:0]
HCRD_PRST
HDAT1_[3:0]
HCMD2
HCMD1
HCLK2
HCLK1
HD+
HD-
4
4
Card Reader Mode
PORT2
PORT1
HOST
USB
SD
SD
I/O
HOST PROCESSOR
2
C control, either