EC5579 datasheet(8/12 Pages) E-CMOS

8 / 12 page

EC5579

18+1 Channel Voltage Buffers for TFT LCD

E-CMOS Corp. (www.ecmos.com.tw)

Page 8 of 12

2007/06/29

Output Phase Reversal

The EC5579 is designed to prevent its output from being phase reversal as long as the input voltage is limited from

VS-－0.5V to VS+ ＋0.5V. Figure 2 shows a photo of the device output with its input voltage driven beyond the supply

rails. Although the phase of the device's output will not be reversed, the input's over-voltage should be avoided. An

improper input voltage exceeds supply range by more than 0.6V may result in an over stress damage.

Figure11. Operation with Beyond-the Rails Input

Power Dissipation

The EC5579 is designed for maximum output current capability. Even though momentary output shorted to ground

causes little damage to the device.

For the high drive amplifier EC5579, it is possible to exceed the 'absolute-maximum junction temperature' under

certain load current conditions. Therefore, it is important to calculate the maximum junction temperature for the

application to determine if load conditions need to be modified for the amplifier to remain in the safe operating area.

The maximum power dissipation allowed in a package is determined according to:

Amax

Jmax

Dmax

Where:

TJmax = Maximum Junction Temperature

TAmax= Maximum Ambient Temperature

JA = Thermal Resistance of the Package

PDmax = Maximum Power Dissipation in the Package.

The maximum power dissipation actually produced by an IC is the total quiescent supply current times the total

power supply voltage, plus the power in the IC due to the loads, or:

PDmax =∑i[VS * ISmax + (VS+ – VO) * IL]

When sourcing, and

PDmax = ∑i[VS * ISmax + (VO – VS-) * IL]

When sinking.

EC5579 Datasheet(PDF) 8 Page - E-CMOS Corporation