SA9102F/SA9102H

sames

5/14

1.

Power calculation

In the Application Circuit (Figure 1), the voltage drop across the shunt will be

between 0 and 16mV (0 to 80A through a shunt resistor of 200µ

Ω). This voltage is

converted to a current of between 0 and 16µA, by means of resistors R

The current sense input saturates at an input current of ±25µA peak.

For the voltage sensor input, the mains voltage (230VAC) is divided down through

a divider to 14V. The current into the A/D converter input is set at 14µA at nominal

mains voltage, via resistor R4 (1M

Ω).

In this configuration, with a mains voltage of 230V and a current of 80A, the output

frequency of the SA9102F and SA9102H power meter chips at FOUT (Pin 12) is

64Hz. In this case 1 pulse will correspond to an energy consumption of 18.4kW/

64Hz = 287.5Ws.

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 duplications of the input currents are generated

for the analog signal processing circuitry.

VOLTAGE

SENSOR

INPUT

DR-00908

IVP

SS

V

CURRENT

SENSOR

INPUTS

IIP

IIN

DD

SS

V

V

SS

V

DD

V

DD

V

GND