3/12

sames

SA9904B

http://www.sames.co.za

Figure 2: Pin connections: Package: PDIP20, SOIC20

Part Number

SA9904BPA

SA9904BSA

Package

PDIP20

SOIC20

ORDERING INFORMATION

PIN DESCRIPTION

Analog Ground. The supply voltage to this pin should be mid-way between

V

and V .

DD

SS

Positive Supply voltage. The voltage to this pin is typically +2.5V if a shunt

resistor is used for current sensing or in the case of a current transformer a

+5V supply can be applied.

GND

Designation

Description

PIN

16

6

Negative Supply Voltage. The voltage to this pin is typically -2.5V if a shunt

resistor is used for current sensing or in the case of a current transformer a

0V supply can be applied.

14

Analog Input for Voltage Phase 1, Phase 2 and Phase 3. The current into the

A/D converter should be set at 14µA

at nominal mains voltage. The voltage

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

RMS

17, 20, 3

IVP1, IVP2,

IVP3

Inputs for current sensors. The shunt resistor voltage from each channel is

converted to a current of 16µA

at rated conditions. The current sense input

saturates at an input current of ±25µA peak.

RMS

18, 19, 1, 2, 4, 5

IIP1, IIN1, IIP2, IIN2,

IIP3, IIN3

This pin provides the connection for the reference current setting resistor.

A 47k

resistor connected to sets the optimum operating condition.

W

15

VREF

Connections for a crystal or ceramic resonator. (OSC1 = input; OSC2 = Output)

10, 11

OSC1, OSC2

Serial clock in. This pin is used to strobe data in and out of the SA9904B

8

SCK

Serial data out. Data from the SA9904B is strobed out on this pin. DO is

only driven when CS is active.

9

DO

Voltage zero crossover. The F50 output generates a pulse, on every

rising edge of the mains voltage for any one phase.

7

F50

Serial data in. Data is only accepted during an active chip select (CS).

12

DI

Chip select. The CS pin is active high.

13

CS

1

IIP2

IVP2

IIN2

IIN1

VREF

IIP1

VSS

IVP3

IIP3

IIN3

VDD

F50

SCK

IVP1

GND

CS

DI

DO

OSC1

OSC2

2

3

4

5

615

14

13

12

11

10

9

8

7

16

17

18

19

20

Dr-01642