AM452 – Voltage-to-current transducer IC

with a differential input

Analog Microelectronics GmbH

An der Fahrt 13, D – 55124 Mainz

February 2008 - Rev 1.2 - Page 9/21

Phone: +49 (0)6131/91 073-0

Fax:

+49 (0)6131/91 073-30

Email: info@analogmicro.de

SET stage

external voltage divider as shown in Figure 2, for example.

Voltage-to-current converter (V/I converter)

The voltage-to-current converter (V/I converter) compares the voltage drop across the

the power dissipation of the output stage.

SET

VI

OP

OUT

I

R

G

V

I

+

⋅

=

0

=

SET

OP

I

R

V

+

0

8

with

0

R

G

V

I

SET

SET

SET

⋅

=

=

0

2R

V

SET

(3)/(4)

Reference voltage source

The reference voltage source (bandgap voltage source) enables voltage to be supplied to

external components (such as sensors, microprocessors, etc.). The reference voltage value

are used (inserted between pin 15 (VREF) and pin 12 (VSET) and between pin 12 (VSET)

and GND).

reference is not in use. It may not undershoot the given minimum value.

Additional operational amplifier OP2

The additional operational amplifier OP2 can be used as a current or voltage source to

supply external components. OP2's positive input must be connected internally to bandgap

range using external resistors.

The individual modules are described separately in the specifications. The reference voltage

source and the operational amplifier OP2 can be operated as independent circuit elements or

modules. Instrumentation amplifier IA, operational amplifier OP1 and the V/I converter form

a unit within the circuit and have the task of converting the voltage input signal into the

required output current.