SA9603C datasheet(12/18 Pages) SAMES

12 / 18 page

SA9603C

sames

12/18

TYPICAL APPLICATIONS

In the Application Circuits (Figures 1 and 2), the components required for power metering

applications, are shown.

In Figure 1, a shunt resistor is used for current sensing. In this application, the circuitry

requires a +2.5V, 0V, -2.5V DC supply.

In the case of Figure 2, when using a current transformer for current sensing, a +5V, 0V

DC supply is sufficient for the circuit.

1, R2 and RSH are the resistors defining the current level into the current sense input.

The values should be selected for an input current of 16µA

RMS into the SA9603C at rated

line current.

Values for RSH of less than 200µ

Ω should be avoided.

1 = R2 = (IL/16µARMS) * RSH/2

Where

= Line current

RSH

= Shunt resistor/termination resistor

3, R6 and R4 set the current for the voltage sense input. The values should be selected

so that the input current into the voltage sense input (virtual ground) is set to 14µA

RMS.

7 defines all on-chip bias and reference currents. With R7 = 24kΩ, optimum conditions

are set.

XTAL is a colour burst TV crystal (f = 3.5795MHz) for the oscillator.

The oscillator

frequency is divided down to 1.7897MHz on-chip to supply the A/D converters and digital

circuitry.

SA9603C Datasheet(PDF) 12 Page - Sames