9

FN6143.2

July 23, 2009

Applications Information

Product Description

The EL5211A voltage feedback amplifier is fabricated using

a high voltage CMOS process. It exhibits rail-to-rail input and

output capability, is unity gain stable, and has low power

consumption (2.5mA per amplifier). These features make

the EL5211A ideal for a wide range of general-purpose

applications. Connected in voltage follower mode and driving

a load of 1k

Ω, the EL5211A has a -3dB bandwidth of 60MHz

while maintaining a 75V/µs slew rate.

Operating Voltage, Input, and Output

The EL5211A is specified with a single nominal supply

voltage from 5V to 15V or a split supply with its total range

from 5V to 15V. Correct operation is guaranteed for a supply

range of 4.5V to 16.5V. Most EL5211A specifications are

stable over both the full supply range and operating

temperatures of -40°C to +85°C. Parameter variations with

operating voltage and/or temperature are shown in the

“Typical Performance Curves” on page 4.

The input common-mode voltage range of the EL5211A

extends 500mV beyond the supply rails. The output swings

of the EL5211A typically extend to within 100mV of positive

and negative supply rails with load currents of 5mA.

Decreasing load currents will extend the output voltage

range even closer to the supply rails. Figure 27 shows the

input and output waveforms for the device in the unity-gain

configuration. Operation is from ±5V supply with a 1k

Ω load

Short Circuit Current Limit

The EL5211A will limit the short circuit current to ±110mA if the

output is directly shorted to the positive or the negative supply.

If an output is shorted indefinitely, the power dissipation could

easily increase such that the device may be damaged.

Maximum reliability is maintained if the output continuous

current never exceeds ±65mA. This limit is set by the design of

the internal metal interconnects.

Pin Descriptions

PIN NUMBER

PIN NAME

FUNCTION

EQUIVALENT CIRCUIT

1

VOUTA

Amplifier A output

2

VINA-

Amplifier A inverting input

3

VINA+

Amplifier A non-inverting input

(Reference Circuit 2)

4

VS-

Negative power supply

5

VINB+

Amplifier B non-inverting input

(Reference Circuit 2)

6

VINB-

Amplifier B inverting input

(Reference Circuit 2)

7

VOUTB

Amplifier B output

(Reference Circuit 1)

8

VS+

Positive power supply

GND

CIRCUIT 1

CIRCUIT 2

5V

5V

10µs

FIGURE 27. OPERATION WITH RAIL-TO-RAIL INPUT AND

OUTPUT

EL5211A