ADE7754 Analog Devices, ADE7754 Datasheet - Page 8

• Manufacturer Part Number: ADE7754
• Description: Poly-phase Multi-Function Energy Metering IC with Serial Port
• Manufacturer: Analog Devices

ADE7754
Pin No.
1
2
3
4
5,6;
7,8;
9,10
11
12
13, 14
15, 16
17
18
MNEMONIC
C F
D G N D
D V
AV
I
I
I
AGND
REF
RESET
IRQ
AP
BP
CP
V
V
, I
, I
, I
BP
DD
N
D D
, V
IN/OUT
AN
BN
, V
CN
;
;
CP
AP
,
PRELIMINARY TECHNICAL DATA
Calibration Frequency logic output. The CF logic output gives Active Power informa-
tion. This output is intended to be used for operational and calibration purposes. The
full-scale output frequency can be scaled by writing to the CFNUM and CFDEN reg-
isters—see Energy To Frequency Conversion.
This provides the ground reference for the digital circuitry in the ADE7754, i.e. multi-
plier, filters and digital-to-frequency converter. Because the digital return currents in
the ADE7754 are small, it is acceptable to connect this pin to the analog ground plane
of the whole system. However high bus capacitance on the DOUT pin may result in
noisy digital current which could affect performance.
Digital power supply. This pin provides the supply voltage for the digital circuitry in
the ADE7754. The supply voltage should be maintained at 5V ± 5% for specified op-
eration. This pin should be decoupled to DGND with a 10µF capacitor in parallel with
a ceramic 100nF capacitor.
Analog power supply. This pin provides the supply voltage for the analog circuitry in
the ADE7754. The supply should be maintained at 5V ± 5% for specified operation.
Every effort should be made to minimize power supply ripple and noise at this pin by
the use of proper decoupling. The typical performance graphs in this data sheet show
the power supply rejection performance. This pin should be decoupled to AGND with a
10µF capacitor in parallel with a ceramic 100nF capacitor.
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.
This pin provides access to the on-chip voltage reference. The on-chip reference has a
nominal value of 2.4V ± 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.
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
single-ended voltage inputs with maximum signal level of ±0.5V with respect to V
specified operation. These inputs are voltage inputs with maximum differential input
signal levels of ±0.5V, ±0.25V and ±0.125V, depending on the gain selections of the
internal PGA - see Analog Inputs.
All inputs have internal ESD protection circuitry, and in addition an over voltage of
±6V can be sustained on these inputs without risk of permanent damage.
Reset pin for the ADE7754. A logic low on this pin will hold the ADCs and digital
circuitry (including the Serial Interface) in a reset condition.
Interrupt Request Output. This is an active low open drain logic output. Maskable
interrupts include: Active Energy Register at half level, Apparent Energy Register at
half level, and waveform sampling up to 26kSPS. See ADE7754 Interrupts.
Analog inputs for current channel. This channel is intended for use with the current
transducer and is referenced in this document as the current channel. These inputs are
fully differential voltage inputs with maximum differential input signal levels of ±0.5V,
±0.25V and ±0.125V, depending on the gain selections of the internal PGA -See Analog
Inputs.
All inputs have internal ESD protection circuitry, and in addition an overvoltage of
±6V can be sustained on these inputs without risk of permanent damage.
PIN FUNCTION DESCRIPTION
– 8 –
DESCRIPTION
REV. PrG 01/03
N
for