mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 115

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

3.8.3.3 12-bit DAC External Reference
For this chip, VREFH and VDDA are available as the DAC reference. When the DAC
uses VREFH as its reference, the ADC uses VREFO, which limits the inputs to 1.2 V for
highest accuracy. However, when the DAC is not used or when the DAC uses VDDA as
its reference, ADC inputs support the full voltage range with no degradation of ADC
accuracy.
3.8.3.4 DAC DMA request
The DAC can generate a DMA request. The DAC generates requests in order to be
updated at the maximum speed. As soon as the DAC is ready to receive new data, it
generates a DMA request, triggering the next DAC data update.
3.8.4 Voltage Reference (VREF) Configuration
This section summarizes how the module has been configured in the chip. For a
comprehensive description of the module itself, see the module’s dedicated chapter.
Freescale Semiconductor, Inc.
System memory map
Power management
Signal multiplexing
Full description
Clocking
Topic
Other peripherals
Table 3-36. Reference links to related information
Port mux control
Related module
MCF51JF128 Reference Manual, Rev. 2, 03/2011
VREF
Figure 3-27. VREF configuration
Transfers
Preliminary
Peripheral
VREF
bridge
Register
access
System memory map
Power management
Signal multiplexing
Clock distribution
Module signals
Reference
VREF
Chapter 3 Chip Configuration
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