ALFAT-OM-337 GHI Electronics, ALFAT-OM-337 Datasheet - Page 43

• Manufacturer Part Number: ALFAT-OM-337
• Description: Memory IC Development Tools ALFAT USB / SD to UART / SPI OEM BOARD
• Manufacturer: GHI Electronics

Specifications of ALFAT-OM-337

• Rohs: yes
• Product: SD OEM Board
• Tool Is For Evaluation Of: SD, SDHC, MMC Cards, USB drives
• Memory Type: Flash
• Operating Supply Voltage: 3.3 V
• Description/function: OEM board offers a seamless way to access files on SD & MMC cards and on USB memory drives
• Interface Type: I2C, SPI, UART, USB
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Part # Aliases: GHI-ALFAT-OM-337

This PHY requires 19.2Mhz clock source. To save the cost of an additional crystal, ALFAT
generates a 19.2Mhz clock at pin 21 that can be used with the PHY.
Important note 1: If ULPI PHY is implemented in the design, the two 22ohm resisters are
still needed to be connected in serial with the data+(DP) and data- (DM) signals.
Important note 2: f ULPI PHY is implemented in the design (like in ALFAT OEM board),
then the USB mass storage device connected to USB1 MUST be initialized in High-Speed
mode (even if the USB device does not support High-Speed mode). Initializing it in Full-
Speed might cause an undesirable performance.
ALFAT tags the modified or created file with the current time and date. To keep track of
time, ALFAT uses the internal real time clock. ALFAT provides two options to the user to
drive the RTC.
The first option is the shared mode, where the RTC runs off the same processor's clock
and power. With this option, the user does not need any external components, and VBAT
should be connected to VCC. But with this option, the hosting system must set the correct
time and date with every power recycle.
The second option is the Backup Mode, where The RTC clocks using the external
32.768Khz crystal and runs off VBAT power through (1.65 to 3.6 V) backup coin battery.
This ensures that the RTC keeps clocking even if the system is powered off. RTC
consumes about 1uA. The system should always keep power available on VBAT pins.
7.5. Real Time Clock
GHI Electronics
Rev. 1.13
Page 43 of 51
Hardware integration guide
ALFAT SoC Processor
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