MCIMX286CVM4B Freescale Semiconductor, MCIMX286CVM4B Datasheet - Page 1477

• Manufacturer Part Number: MCIMX286CVM4B
• Description: IC MPU I.MX286 289MAPBGA
• Manufacturer: Freescale Semiconductor
• Series: i.MX28r

Specifications of MCIMX286CVM4B

• Core Processor: ARM9
• Core Size: 32-Bit
• Speed: 454MHz
• Connectivity: CAN, EBI/EMI, Ethernet, I²C, MMC, SmartCard, SPI, SSI, UART/USART, USB OTG
• Peripherals: DMA, I²S, LCD, POR, PWM, WDT
• Program Memory Size: 128KB (32K x 32)
• Program Memory Type: Mask ROM
• Ram Size: 32K x 32
• Voltage - Supply (vcc/vdd): 1.25 V ~ 5.25 V
• Data Converters: A/D 17x12b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 289-LFBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Number Of I /o: -
• Eeprom Size: -
• Lead Free Status / Rohs Status: Compliant

Chapter 22
Real-Time Clock Alarm Watchdog Persistent Bits
22.1 RTC Overview
The real-time clock (RTC) and alarm share a one-second pulse time domain. The watchdog
reset and millisecond counter run on a one-millisecond time domain. The RTC, alarm, and
persistent bits use persistent storage and reside in a special power domain (crystal domain)
that remains powered up even when the rest of the chip is in its powered-down state.
22-1
Upon battery insertion, the crystals (32-KHz and 24-MHz) are in a quiescent state. The
activation of these crystals is under software control through the RTC persistent bits, as
described later in this chapter.
The one-second time base is derived either from the 24.0-MHz crystal oscillator or a 32-KHz
crystal oscillator (which can be either exactly 32.0 KHz or 32.768 KHz), as controlled by
bits in Persistent Register 0. The time base thus generated is used to increment the value of
Freescale Semiconductor, Inc.
• The XTAL32KHZ_PWRUP bit in the Persistent Register 0 controls the activity of the
• The XTAL24MHZ_PWRUP bit in the Persistent Register 0 controls the behavior of
32-KHz crystal at all times (chip power on or off).
the 24-MHz crystal during the power-off state. (The 24-MHz crystal is always on when
the chip is powered up.)
illustrates this block.
The term power-down, as used here, refers to a state in which the
DC-DC converter and various parts of the crystal power domain
are still powered up, but the rest of the chip is powered down. If
the battery is removed, then the persistent bits, the alarm value,
and the second counter value will be lost. The crystal power
domain powers both the 32-KHz and 24-MHz crystals.
i.MX28 Applications Processor Reference Manual, Rev. 1, 2010
Note
Figure
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