MCIMX251AVM4 Freescale Semiconductor, MCIMX251AVM4 Datasheet - Page 16

• Manufacturer Part Number: MCIMX251AVM4
• Description: IC MPU I.MX25 AUTO 400MAPBGA
• Manufacturer: Freescale Semiconductor
• Series: i.MX25r

Specifications of MCIMX251AVM4

• Core Processor: ARM9
• Core Size: 32-Bit
• Speed: 400MHz
• Connectivity: 1-Wire, CAN, EBI/EMI, Ethernet, I²C, MMC, SmartCard, SPI, SSI, UART/USART, USB OTG
• Peripherals: DMA, I²S, POR, PWM, WDT
• Number Of I /o: 128
• Program Memory Type: External Program Memory
• Ram Size: 144K x 8
• Voltage - Supply (vcc/vdd): 1.15 V ~ 1.52 V
• Data Converters: A/D 3x12b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 400-LFBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

3.2
Any i.MX25 board design must comply with the power-up and power-down sequence guidelines given in
this section to ensure reliable operation of the device. Recommended power-up and power-down
sequences are given in the following subsections.
3.2.1
The following power-up sequence is recommended:
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1. Assert power on reset (POR).
2. Turn on digital logic domain and I/O power supplies VDDn and NVCCx.
3. Turn on all other analog power supplies, including USBPHY1_VDDA_BIAS,
4. Negate the POR signal.
USBPHY1_UPLL_VDD, USBPHY1_VDDA, USBPHY2_VDD, OSC24M_VDD,
MPPLL_VDD, UPLL_VDD, NVCC_ADC, and FUSEVDD (FUSEVDD is tied to GND if fuses
are not being programmed). The minimum time between turning on each power supply is the time
it takes for the previous supply to be stable.
Supply Power-Up/Power-Down Requirements and Restrictions
Power-Up Sequence
Deviations from the guidelines in this section may result in the following
situations:
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•
•
For security applications, the coin battery must be connected during both
power-up and power-down sequences to ensure that security keys are not
unintentionally erased.
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•
•
Excessive current during power-up phase
Prevention of the device from booting
Irreversible damage to the i.MX25 (worst-case scenario)
The user is advised to connect FUSEVDD to GND except when fuses
are being programmed, in order to prevent unintentional blowing of
fuses.
Other power-up sequences may be possible; however, the above
sequence has been verified and is recommended.
There is a 1-ms minimum time between supplies coming up, and a 1-ms
minimum time between POR_B assert and deassert.
i.MX25 Applications Processor for Automotive Products, Rev. 8
CAUTION
NOTE
NOTE
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