pc87591l National Semiconductor Corporation, pc87591l Datasheet - Page 192

• Manufacturer Part Number: pc87591l
• Description: Lpc Mobile Embedded Controllers
• Manufacturer: National Semiconductor Corporation

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Embedded Controller Modules
4.12.4 Operation
Initializing the DAC
The PC87591x wakes up after power-up with all the D/A channels disabled (DACEN0-3 bits in DACCTRL register are
cleared to 0). In this state, all DAC activities are halted, and its current consumption is reduced to zero.
DACDATn registers (n=0 to 3) must be initialized to 00
in DACCTRL register to 1.
Enabling and Disabling the DAC
Enabling the DAC. Each channel of the DAC is enabled independently by setting its DACEN bit. After enabling, it settles to
the value stored in DACDATn register after the specified settling time.
Disabling the DAC. The DAC channels may be independently disabled in order to reduce current consumption by clearing
the corresponding DACENn (n=0 to 3) bit in DACCTRL register. In this case, the output pin drives 0V, even if the respective
DACDATn register does not contain 00
PC87591x
AV
IDLE
16
CC
.
Figure 67. DAC Functional Diagram
AV
(Continued)
CC
VREF
VREF
VREF
VREF
16
, or according to the required output level, before setting DACEN0-3
DACDAT0
DACDAT1
DACDAT2
DACDAT3
Peripheral Bus
Register
AV
to other
modules
Control
192
DAC0
DAC1
DAC2
DAC3
DAC
CC
Analog
Power
3.3V
DAC
AGND
DA0
DA1
DA2
DA3
Revision 1.07