2 manual channel selection, 2 anti-tampering on voltage, 7 energy pulse generation – Cirrus Logic CS5480 User Manual

Page 25: Cs5480, Value. vf, Has no phase relationship to i1, Or i2, Therefore, the vf, Only affects the active power calculation paths

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CS5480

DS980F3

25

5.6.1.2 Manual Channel Selection

In addition to automatic channel selection anti-tamper-
ing scheme, the CS5480 allows the user or application
program to select the more appropriate energy channel
manually. Configuration 2 (Config2) register bit IHOLD
disable automatic channel selection, and ICHAN forces
the selection of the contributor to the total power regis-
ters (see

Figure 14

).

5.6.2 Anti-tampering on Voltage

An internal RMS voltage reference is also available in
the event that the voltage input has been compromised
by tampering.
If the user application detects the voltage input has
been impaired, it may choose to use the fixed internal
RMS voltage reference in active power calculations by
setting the VFIX bit in the Configuration 2 (Config2) reg-
ister. The value of the Voltage Fixed RMS Reference

(VF

RMS

) register is by default 0.707107 (full-scale RMS)

but can be changed by the application program.

Figure

14

shows the entry point for the VF

RMS

value. VF

RMS

has no phase relationship to I1

RMS

or I2

RMS

. Therefore,

the VF

RMS

only affects the active power calculation

paths.

5.7 Energy Pulse Generation

The CS5480 provides three independent energy pulse
generation blocks (EPG1, EPG2, and EPG3) in order to
simultaneously output active, reactive, and apparent
energy pulses on any of the three digital output pins
(DO1, DO2, and DO3). The energy pulse frequency is
proportional to the magnitude of the power. The energy
pulse output is commonly used as the test output of a
power meter. The host microcontroller can also use the
energy pulses to accumulate the energy (see Figure 16).

P

SUM

Sign

Q

SUM

Sign

P1 Sign

P2 Sign

Q1 Sign

Q2 Sign

DO1_OD
(Config1)

DO2_OD
(Config1)

DO3_OD
(Config1)

(PulseCtrl) EPGxIN[3:0]

DOxMODE[3:0]

(Config1)

DO3

DO2

DO1

Hi-Z

Interrupt

P

SUM

Q

SUM

S

SUM

P1

AVG

P2

AVG

Q1

AVG

Q2

AVG

S1

AVG

S2

AVG

PULSE RATE

EPGx_ON

(Config1)

MCLK

(PulseWidth) PW[7:0]

(PulseWidth) FREQ_RNG[3:0]

0000

0001

0010

0011

0100

0101

0110

0111

1000

E

n

e

rgy

Pu

ls

e

G

e

ne

ra

ti

on

(

E

PG

1)

En

e

rg

y

Pul

s

e

G

e

n

e

ra

ti

o

n

(

E

PG

2

)

E

n

er

gy

P

u

ls

e G

e

n

e

ra

ti

o

n

(

E

P

G

3

)

4

4

8

4

D

igi

ta

l O

u

tp

ut

M

u

x

(

D

O

3

)

D

igi

ta

l O

u

tp

ut

M

u

x

(

D

O

2

)

0000

0001

0010

0011

0100

0101

0110

0111

1000

1001

1010

1011

1100

1101

1110

1111

D

igi

ta

l O

u

tp

ut

M

u

x

(

D

O

1

)

RESERVED

RESERVED

RESERVED

V1/V2 Crossing

I1/I2 Crossing

Figure 16. Energy Pulse Generation and Digital Output Control

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