SA9604A

sames

5/20

1.

Power calulation

In the Application Circuit (Figure 1), the voltages from Line 1, Line 2 and Line 3, are

converted to currents and applied to the voltage sense inputs IVN1, IVN2 and IVN3.

The current levels on the voltage sense inputs are derived from the mains voltage

(3 x 230 V

input currents into the A/D converters are 14µA

R

For the current sense inputs, the voltages across the current transformers terminating

resistors are converted to currents of 16µA

resistors R

The signals providing the current information are applied to the current sensor

inputs: IIN1; IIP1; IIN2; IIP2; IIN3; and IIP3.

2.

Analog Input Configuration

The input circuitry of the current and voltage sensor inputs are illustrated below.

These inputs are protected against electrostatic discharge through clamping

diodes.

The feedback loops from the outputs of the amplifiers A

shorts on the signal inputs. Exact copies of the input currents are generated for the

following analog signal processing circuitry.

IV P

DR -0 130 8

VOL T AGE

SE NS OR

IN PU T

SS

V

II N

II P

CU RR EN T

SE NS OR

IN PUT S

DD

V

SS

V

SS

V

DD

V

DD

V

GN D

3.

Electrostatic Discharge (ESD), Protection

The SA9604A Integrated Circuits inputs/outputs are protected against ESD.