EC5601

High Slew Rate Rail-to-Rail Single

Operational Amplifiers with OTP

2010/11/29

Page 5 of 11

JA

Amax

Jmax

Θ

T

-

T

Figure 2. Operation with Beyond-the Rails Input

Power Dissipation

The EC5601 is designed for maximum output

current capability. Even though momentary output

shorted to ground causes little damage to device.

For the high drive amplifier EC5601, 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:

Where:

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:

When sourcing, and

When sinking.

Where:

i = 1 to 1

VS = Total Supply Voltage

VO = Maximum Output Voltage of the Application

overheat can be easily solved by setting the two

Driving Capacitive Loads

The EC5601 is designed to drive a wide range of

capacitive loads. In addition, the output current

handling capability of the device allows for good

slewing characteristics even with large capacitive

loads. The combination of these features make the

EC5601 ideally for applications such as TFT LCD

panel grayscale reference voltage buffers, ADC input

amplifiers, etc.

As load capacitance increases, however, the -3dB

bandwidth of the device will decrease and the

peaking increase. Depending on the application, it

must be necessary to reduce peaking and to improve

device stability. To improve device stability, a small

v al u e of series resistor (usually between 5Ωand

50Ω) must be placed in series with the output.

The advantage is that it improves the settling and

overshooting performance with very large capacitive

loads. Figure 3. shows the typical

application

configuration.

Figure 3. Typical Application Configuration.

Power Supply Bypassing and Printed Circuit

Board Layout

With high phase margin, the EC5601 performs

stable gain at high frequency. Like any high-

frequency device, good layout of the printed circuit

board usually comes with optimum performance.

Ground plane construction is highly recommended,

lead lengths should be as short as possible and the

power supply pins must be well bypassed to reduce

the risk of oscillation. For normal single supply

a 0.1 µF ceramic capacitor should be placed from

tantalum capacitor should then be connected in

parallel, placed in the region of the amplifier. One

4.7µF capacitor may be used for multiple devices.

This same capacitor combination should be placed at

each supply pin to ground if split supplies are to be

used.