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Download Epson SED1278F/D Specifications
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SED1240 Series 2 Using only the voltage regulating circuit and the voltage follower. [When using no V5 voltage regulating built-in resistor] (Example of VSS2 = VSS) SED124XDXX VSS VSS2 CAP1+ CAP1– CAP2+ CAP2– VOUT SED124XDXX VSS VSS2 CAP1+ CAP1– CAP2+ CAP2– VOUT External power supply External power supply [When using a V5 voltage regulating built-in resistor] (Example of VSS2 = VSS) R3 V5 VR V5 VR R2 R1 VDD, V0 VDD, V0 C2 C2 C2 C2 C2 C2 C2 C2 C2 C2 V1 V2 V3 V4 V5 VS1 V1 V2 V3 V4 V5 VS1 C2 C2 C2 C2 C2 (Example of VSS2 = VSS) SED124XDXX VSS VSS2 CAP1+ CAP1– CAP2+ CAP2– VOUT SED124XDXX VSS VSS2 CAP1+ CAP1– CAP2+ CAP2– VOUT V5 VR VR VDD, V0 VDD, V0 V1 V2 V3 V4 V5 VS1 V1 V2 V3 V4 V5 VS1 External power supply External power supply (Example of VSS2 = VSS) Reference set values: C1: 0.47 to 4.7 µF It is recommended to set optimum values suitable for the panel size in C2: 0.1 to 4.7 µF capacitors C1 and C2 while watching the liquid crystal display and drive waveforms. *1 Because the input impedance of the VR pin is high, use a short wire and a shielding wire. *2 Determine C1 and C2 values depending on the size of the LCD panel to be driven. Set proper values that permit stabilizing the liquid crystal drive voltages. [Setting example] • Turn on the voltage regulating circuit and the voltage follower and give a voltage to VOUT from the outside. • Display a LCD heavy load pattern like horizontal stripes and determine a C2 value so that the liquid crystal drive voltages (V1 to V5) may be stabilized. However, it is necessary to set the same capacity value in C2 in every case. • Next, turn on the built-in power supply and determine a C1 value. 8–20 EPSON
