sed1355 ETC-unknow, sed1355 Datasheet - Page 377

• Manufacturer Part Number: sed1355
• Description: Sed1355 Embedded Ramdac Lcd/crt Controller
• Manufacturer: ETC-unknow

Epson Research and Development
Vancouver Design Center
1 SED1355 Power Consumption
Power Consumption
Issue Date: 98/10/30
SED1355 power consumption is affected by many system design variables.
• Input clock frequency (CLKI): the CLKI frequency determines the LCD frame-rate, CPU perfor-
• CPU interface: the SED1355 current consumption depends on the BUSCLK frequency, data
• V
• Display mode: the resolution and color depth affect power consumption – the higher the
• Internal CLK divide: internal registers allow the input clock to be divided before going to the
There are two power save modes in the SED1355: 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 SED1355 to
• CPU bus state during SUSPEND: the state of the CPU bus signals during SUSPEND has a
• CLKI state during SUSPEND: disabling the CLKI during SUSPEND has substantial power
mance to memory, and other functions – the higher the input clock frequency, the higher the
frame-rate, performance and power consumption.
width, number of toggling pins, and other factors – the higher the BUSCLK, the higher the CPU
performance and power consumption.
higher the consumption.
resolution/color depth, the higher the consumption.
internal logic blocks – the higher the divide, the lower the power consumption.
disable the internal memory clock thereby saving power.
substantial effect on power consumption. An inactive bus (e.g. BUSCLK = low, Addr = low etc.)
reduces overall system power consumption.
savings.
DD
voltage level: the voltage level affects power consumption – the higher the voltage, the
X23A-G-006-02
SED1355
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