REV. PrB 08/01

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PRELIMINARY TECHNICAL DATA

ADE7752

PIN FUNCTION DESCRIPTION

Pin No.

MNEMONIC

DESCRIPTION

1

C F

Calibration Frequency Logic Output. The CF logic output gives instantaneous real

power information. This output is intended to be used for calibration purposes. Also see

SCF pin description.

2

DGND

This provides the ground reference for the digital circuitry in the ADE7752, i.e. multi-

plier, filters and digital-to-frequency converter. Because the digital return currents in

the ADE7752 are small, it is acceptable to connect this pin to the analog ground plane

of the whole system - see Applications Information. However high bus capacitance on the

DOUT pin may result in noisy digital current which could affect performance.

3

Power supply. This pin provides the supply voltage for the digital circuitry in the

ADE7752. The supply voltage should be maintained at 5V ± 5% for specified opera-

tion. This pin should be decoupled to DGND with a 10µF capacitor in parallel with a

ceramic 100nF capacitor.

4

REVP

This logic output will go logic high when negative power is detected on any of the three

phase inputs, i.e., when the phase angle between the voltage and the current signals is

greater that 90°. This output is not latched and will be reset when positive power is

once again detected. The output will go high or low at the same time as a pulse is is-

sued on CF.

5,6;

Analog inputs for current channel. This channel is intended for use with the current

7,8;

transducer and is referenced in this document as the current channel. These inputs are

9,10

fully differential voltage inputs with maximum differential input signal levels of

±0.125V -See Analog Inputs. Both inputs have internal ESD protection circuitry, and in

addition an overvoltage of ±6V can be sustained on these inputs without risk of perma

nent damage.

11

AGND

This pin provides the ground reference for the analog circuitry in the ADE7754, i.e.

ADCs, temperature sensor, and reference. This pin should be tied to the analog ground

plane or the quietest ground reference in the system. This quiet ground reference

should be used for all analog circuitry, e.g. anti aliasing filters, current and voltage

transducers etc. In order to keep ground noise around the ADE7754 to a minimum, the

quiet ground plane should only connected to the digital ground plane at one point. It is

acceptable to place the entire device on the analog ground plane - see Applications Informa-

tion.

12

This pin provides access to the on-chip voltage reference. The on-chip reference has a

nominal value of 2.5V ± 8% and a typical temperature coefficient of 30ppm/°C. An

external reference source may also be connected at this pin. In either case this pin

should be decoupled to AGND with a 1µF ceramic capacitor.

13-16

Analog inputs for the voltage channel. This channel is intended for use with the voltage

transducer and is referenced as the voltage channel in this document. These inputs are

for specified operation. All inputs have internal ESD protection circuitry, and in addi

tion an over voltage of ±6V can be sustained on these inputs without risk of permanent

damage.

17

RESET

Reset pin for the ADE7752. A logic low on this pin will hold the ADCs and digital

circuitry (including the Serial Interface) in a reset condition.

18

S C F

Select Calibration Frequency. This logic input is used to select the frequency on the

calibration output CF. Table IV shows how the calibration frequencies are selected.