MAX14502AETL+ Maxim Integrated Products, MAX14502AETL+ Datasheet - Page 24

• Manufacturer Part Number: MAX14502AETL+
• Description: IC CARD READER USB-SD 40-TQFN
• Manufacturer: Maxim Integrated Products
• Type: Smart Card Interface ICr

Specifications of MAX14502AETL+

• Applications: USB
• Interface: I²C
• Voltage - Supply: 1.8 V ~ 3.3 V
• Package / Case: 40-TQFN Exposed Pad
• Mounting Type: Surface Mount
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

grammed to stay asserted until the status register is
read, or stay asserted for 10ms. If INT is programmed to
stay asserted, a read to the status register is required to
clear INT. INT can be programmed to be active-high or
active-low when I2C_SEL is high (I
high impedance in Sleep mode (WAKEUP = 0), regard-
less of the INT polarity programmed in the I
Use a pullup or pulldown resistor for the desired inactive
INT polarity state during Sleep mode.
All interrupts are masked at power-up. While masked
interrupts do not assert the INT output, they do register
as changes in the interrupt request registers (IRQ1 and
IRQ2). The status register (STATUS1 = 0x12) indicates
the current state of the interrupt bits. If interrupts are
masked, polling IRQ1 and IRQ2 indicate the fields with
changes, and STATUS1 gives the current state.
Reading the IRQ registers resets the interrupt request
bits. If polling is used to read the device status, it is
required to read both the status register and the inter-
rupt request registers to check for state changes.
Hi-Speed USB-to-SD Card
Readers with Bypass
Table 2. Control Register (0x00)
24
[7:5]
[2:1]
BIT
4
3
0
______________________________________________________________________________________
RESERVED
SD PORT 2 ANALOG SWITCHES
SD Port 2 is a set of six analog switches connecting the SD port to the
SD card. This set contains: clock (CCLK2), command (CCMD2), and
four data lines (CDAT2_[3:0]). The card-present line is not available
for this port. This setting is ignored when Card Reader mode is
enabled for this port.
SD PORT 1 ANALOG SWITCHES
SD Port 1 is a set of seven analog switches connecting the SD port to
the SD card. This set contains: card-present (CCRD_PRST), clock
(CCLK1), command (CCMD1), and four data lines (CDAT1_[3:0]). The
difference between Port 1 and Port 2 is the card-present line. This
setting is ignored when Card Reader mode is enabled for this port.
CARD READER MODE
Changing these bits in Sleep mode does not execute the action until
the host µP wakes up the MAX14500–MAX14503.
WAKEUP
In Sleep mode, the MAX14500–MAX14503 are in Pass Thru mode. SD
port switches are controlled by their respective bits. Entering Sleep
mode reduces the supply current by turning off the internal logic.
Request to shut down may be delayed due to USB and de-
enumeration.
DESCRIPTION
2
Interrupt Masking
C control). INT is
2
C registers.
When enabled, the INT output asserts an interrupt for
changes in the USB connection and if the operating
system suspends the USB connection. VBUS is detect-
ed at the KVBUS input and changes in VBUS voltage
can assert an interrupt when enabled.
The MAX14500–MAX14503 feature many advanced
power-saving modes. V
be applied for I
V
ferent power-saving modes (see the Power-Supply
Modes section).
When enabled, changes in the BSY bit can assert an
interrupt (see the Busy Indication (BSY) section).
When enabled, the SDSTAT bit asserts an interrupt for
card detection and removal upon entering Card Reader
mode for the SD card socket configured as the card
reader. The SDSTAT bit is not active during Pass Thru
mode and does not change states in the IRQ registers
upon card insertion and removal during Pass Thru mode.
TM
can assert an interrupt when enabled to indicate dif-
VALUE
00, 11
000
01
10
0
1
0
1
0
1
2
C communication. Changes in V
Set these bits to 0.
Analog switches are open,
disconnecting the SD port
from the SD card.
Analog switches are
closed, connecting the SD
port to the SD card.
Analog switches are open,
disconnecting the SD port
from the SD card.
Analog switches are
closed, connecting the SD
port to the SD card.
Card Reader mode not
active.
Card Reader mode active:
Connects to SD card 1.
Card Reader mode active:
Connects to SD card 2.
Request internal logic to
shut down.
Wake up internal logic.
CC
, V
FUNCTION
SD
Power-Supply Interrupts
, and V
SD Status Interrupt
TM
USB Interrupts
Busy Interrupt
do not need to
DEFAULT
SD
000
00
1
1
0
and