Philips S1D13505 Computer Monitor User Manual


 
Epson Research and Development
Page 3
Vancouver Design Center
Power Consumption S1D13505
Issue Date: 01/02/05 X23A-G-006-03
1 S1D13505 Power Consumption
S1D13505 power consumption is affected by many system design variables.
Input clock frequency (CLKI): the CLKI frequency determines the LCD frame-rate, CPU perfor-
mance to memory, and other functions the higher the input clock frequency, the higher the
frame-rate, performance and power consumption.
CPU interface: the S1D13505 current consumption depends on the BUSCLK frequency, data
width, number of toggling pins, and other factors the higher the BUSCLK, the higher the CPU
performance and power consumption.
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voltage level: the voltage level affects power consumption the higher the voltage, the
higher the consumption.
Display mode: the resolution and color depth affect power consumption the higher the
resolution/color depth, the higher the consumption.
Internal CLK divide: internal registers allow the input clock to be divided before going to the
internal logic blocks the higher the divide, the lower the power consumption.
There are two power save modes in the S1D13505: Software and Hardware SUSPEND. The power
consumption of these modes is affected by various system design variables.
DRAM refresh mode (CBR or self-refresh): self-refresh capable DRAM allows the S1D13505 to
disable the internal memory clock thereby saving power.
CPU bus state during SUSPEND: the state of the CPU bus signals during SUSPEND has a
substantial effect on power consumption. An inactive bus (e.g. BUSCLK = low, Addr = low etc.)
reduces overall system power consumption.
CLKI state during SUSPEND: disabling the CLKI during SUSPEND has substantial power
savings.