INDUSTRIAL VOLTAGE AMPLIFIER IC

AM401

analog microelectronics

Mars 2006

Analog Microelectronics GmbH

Phone:

+49 (0)6131/91 073 – 0

9/21

An der Fahrt 13, D – 55124 Mainz

Fax:

+49 (0)6131/91 073 – 30

Rev. 2.3

Internet: http://www.analogmicro.de

Email:

info@analogmicro.de

()

BG

REF

BG

OFFSET

V

V

R

R

V

V

−

−

=

3

4

(3)

The following applies to the IC’s actual output voltage

VOUT (transfer function of OP1):

INOP

OP

OUT

V

G

V

⋅

=

(4)

with an adjustable gain of

GOP:

1

2

1 +

=

R

R

GOP

(5)

Setting the voltage amplification

The gain of operational amplifier stage OP1 can be set using the suitably selected external resistors

R1 and R2. If OP1 is connected up as a non-inverting amplifier (see: Figure2) output voltage VOUT at

pin VOUT is calculated as follows:

1

OP

IN

OUT

G

V

V

⋅

=

with

1

2

1

1

+

=

R

R

G

OP

where VIN is the voltage at OP1’s input pin INOP.

Selecting the supply voltage

In principle AM401 can be used across the entire supply voltage range defined herein. However,

depending on the output voltage selected and the circuitry of the remaining components certain

boundary conditions apply when selecting VCC:

• When using voltage output pin VOUT the IC’s minimum supply voltage VCC necessary for the

operation of the device depends on the maximum output voltage VOUTmax required by the

application. The following applies:

V

5

max +

≥

OUT

CC

V

V

(6)

• If the additional operational amplifier OP2 is used as a voltage reference or current source, the

minimum supply voltage selected (VCC) depends on the maximum voltage at pin CVREF. The

following applies:

V

5

max +

≥

CVREF

CC

V

V

(7)

When using pin VOUT and operational amplifier OP2 as a voltage reference or current source the

higher value of Vcc must be set.