CS5466

4

DS659F1

2.

PIN DESCRIPTION

Clock Generator

Crystal Out

Crystal In

1, 24

XOUT, XIN - A single stage amplifier inside the chip is connected to these pins and can be used

with a crystal to provide the system clock for the device. Alternatively, an external clock can be

supplied to the XIN pin to provide the system clock for the device.

CPU Clock Output

2

CPUCLK - Output of on-chip oscillator which can drive one standard CMOS load.

Control Pins

Gain Select

5, 7

IGAIN1, IGAIN0 - Used to select the current channel input gain range.

Frequency Select

High Pass Filter Enable

8

HPF - High disables the HPF. Low activates HPF on Voltage channel. Connecting HPF pin to

FOUT pin activates HPF on Current channel.

Reset

19

RESET - Low activates Reset.

Energy Pulse Outputs

Energy Output

22, 21

E1, E2 - Active low alternating pulses with an output frequency that is proportional to the active

(real) power.

High Freq Output

18

FOUT - Outputs energy pulses at a frequency higher than E1 and E2 outputs. Used for calibra-

tion purposes.

Neg Energy Indicator

6

NEG - High indicates negative energy.

Analog Inputs/Outputs

Differential Voltage Inputs

9, 10

VIN+, VIN- - Differential analog input pins for voltage channel.

Voltage Reference

Output

11

VREFOUT - The on-chip voltage reference output pin. The voltage reference has a nominal

magnitude of 2.5 V and is referenced to the AGND pin on the converter.

Voltage Reference Input

12

VREFIN - Voltage input to this pin establishes the voltage reference for the on-chip modulators.

Differential Current Inputs

16, 15

IIN+, IIN- - Differential analog input pins for current channel.

Power Supply Connections

Positive Digital Supply

3

VD+ - The positive digital supply.

Digital Ground

4

DGND - Digital Ground.

Analog Ground

13

AGND - Analog Ground.

Positive Analog Supply

14

VA+ - The positive analog supply.

VREFIN

12

Voltage Reference Input

VREFOUT

11

Voltage Reference Output

VIN-

10

Differential Voltage Input

VIN+

9

Differential Voltage Input

HPF

8

High-pass Filter Enable

IGAIN1

7

Gain Select 1

NEG

6

Negative Energy Indicator

IGAIN0

5

Gain Select 0

DGND

4

Digital Ground

VD+

3

Positive Power Supply

CPUCLK

2

CPU Clock Output

XOUT

1

Crystal Out

AGND

13

Analog Ground

VA+

14

Positive Analog Supply

IIN-

15

Differential Current Input

IIN+

16

Differential Current Input

FREQ2

17

Frequency Select 2

FOUT

18

High-frequency Output

RESET

19

Reset

FREQ1

20

Frequency Select 1

E2

21

Energy Output 2

E1

22

Energy Output 1

FREQ0

23

Frequency Select 0

XIN

24

Crystal In