MAX14502AETL+ Maxim Integrated Products, MAX14502AETL+ Datasheet - Page 26

• 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

Hi-Speed USB-to-SD Card
Readers with Bypass
Drive RST low to reset all the registers to the default
value and minimize the supply current.
The MAX14500–MAX14503 can be put to sleep by pro-
gramming the WAKEUP bit to 0 in the control register
with I
simple control. This turns off the internal microcontroller
to minimize current. Reads and writes to the I
functional, and registers can be updated with new val-
ues. Most register actions do not take effect until the
internal microcontroller wakes up or when Card Reader
mode is enabled. The SD port analog switches can
26
Figure 12. Typical Interrupt Servicing Flowchart
______________________________________________________________________________________
2
C control, or by driving the MODE input low in
NOTE: THIS IS VALID FOR I
NO
NO
2
C CONTROL ONLY
INTACTHI FIELD SETTINGS
• INTERRUPT STATUS
• INTERRUPT REQUEST
REGISTER BIT UPDATED
REGISTER BIT SET
INT ENABLED-BASED
INTERRUPT ACTIVITY
INTERRUPT STATUS
ON INTPULSE AND
IS INTERRUPT
Reset ( RST )
CHANGED?
ENABLED?
MASK BIT
OCCURS
HAS
YES
YES
2
C are still
Sleep
RUNTIME
change states while the internal microcontroller is in
Sleep mode. The Register Map section shows which
registers are enabled in Sleep mode, at power-up, and
upon entering Card Reader mode.
The MAX14500–MAX14503 come preprogrammed to
accept a 12MHz, 13MHz, 19.2MHz, or 26MHz default
clock input with the clock squarer enabled for low-
amplitude TCXO signals (see the Ordering
Information/Selector Guide ). This clock is used for the
USB and SD subsystems and is not required for opera-
tion of the I
to be changed in the system. The PLL subsystem con-
REQUEST REGISTERS
INT ENABLED?
INTERRUPT
CLEAR INT
READ?
YES
YES
IS
2
C interface. This allows the clock frequency
NO
Clock Configuration
NO