SED1374 Datasheet, PDF (275/420 Pages) Epson Company – SED1374 Embedded Memory Color LCD Controller

Epson Research and Development
Vancouver Design Center
Page 3
1 SED1374 Power Consumption
SED1374 power consumption is affected by many system design variables.
• Input clock frequency (CLKI): the CLKI frequency and the internal clock divide register deter-
mine the operating clock (CLK) frequency of the SED1374. The higher CLK is, the higher the
frame fate, performance, and power consumption.
• CPU interface: the SED1374 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.
• V_DD voltage levels (Core and IO): the voltage level of the Core and IO sections in the SED1374
affects power consumption – the higher the voltage, the higher the consumption.
• Display mode: the resolution, panel type, and color depth affect power consumption. The higher
the resolution/color depth and number of LCD panel signals, the higher the power consumption.
Note
If the High Performance option is turned on, the power consumption increases to that of
8 bit-per-pixel mode for all color depths.
There are two power save modes in the SED1374: Software and Hardware Power Save. The power
consumption of these modes is affected by various system design variables.
• CPU bus state during Power Save: the state of the CPU bus signals during Power Save 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 Power Save: disabling the CLKI during Power Save has substantial power
savings.
Power Consumption
Issue Date: 98/10/27
SED1374
X26A-G-006-01