MCIMX281AVM4B Freescale Semiconductor, MCIMX281AVM4B Datasheet - Page 1775

• Manufacturer Part Number: MCIMX281AVM4B
• Description: IC MPU I.MX28 1.2 289MAPBGA
• Manufacturer: Freescale Semiconductor
• Series: i.MX28r

Specifications of MCIMX281AVM4B

• 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: Supplier Unconfirmed

Chapter 28
Pulse-Width Modulator (PWM) Controller
28.1 Pulse Width Modulator (PWM) Overview
The device has eight PWM output controllers that can be used in place of GPIO pins.
Applications include HSADC driving signals and LED & backlight brightness control.
Independent output control of each phase allows 0, 1, or high-impedance to be independently
selected for the active and inactive phases. Individual outputs can be run in lock step with
guaranteed non-overlapping portions for differential drive applications.
Figure 28-1
DMA. Initial values of Period, Active, and Inactive widths are set for each desired channel.
The outputs are selected by phase and then the desired PWM channels are simultaneously
enabled. This effectively launches the PWM outputs to autonomously drive their loads
without further intervention.
28.2 Operation
Each PWM channel has two control registers that are used to specify the channel output:
HW_PWM_ACTIVEn and HW_PWM_PERIODn.
When programming a channel, it is important to remember that there is an order dependence
for register writes.
The hardware waits for a HW_PWM_PERIODn register write to update the hardware with
the values in both registers. This register write order dependence allows smooth on-the-fly
reprogramming of the channel. Also, when the user reprograms the channel in this manner,
Freescale Semiconductor, Inc.
• The HW_PWM_ACTIVEn register must be written first, followed by
• If the order is reversed, the parameters written to the HW_PWM_ACTIVEn register
HW_PWM_PERIODn.
will not take effect in the hardware.
shows the block diagram of the PWM controller. The controller does not use
i.MX28 Applications Processor Reference Manual, Rev. 1, 2010
1775