CS5463
The pulse output frequency of E1 is directly proportional
to the active power calculated from the input signals. To
calculate the output frequency on E1, the following
transfer function can be utilized:
With MCLK = 4.096 MHz and default settings, the puls-
es will have an average frequency equal to the frequen-
cy specified by PulseRate when the input signals
applied to the voltage and current channels cause
full-scale readings in the instantaneous voltage and cur-
rent registers. The maximum pulse frequency from the
E2 (and/or E3) pin is (MCLK/K)/2048. The E2 (and/or
E3) pin outputs apparent energy, but has no energy di-
rection indicator.
VIN × VGAIN × IIN × IGAIN × PF × PulseRate
FREQ = --------------------------------------------------------------------------------------------------------------------------------
P
2
VREFIN
FREQ = Average frequency of active energy E1 pulses [Hz]
P
VIN = rms voltage across VIN+ and VIN- [V]
VGAIN = Voltage channel gain
IIN = rms voltage across IIN+ and IIN- [V]
IGAIN = Current channel gain
5.5.3 Reactive Energy Mode
Reactive energy pulses are output on pin E3 by setting
bit E3MODE1:0 = 0 (default) in the Operational Mode
Register. Positive reactive energy is registered by E3
falling when E2 is high. Negative reactive energy is reg-
istered by E3 falling when E2 is low. Figure 5 on
page 17 illustrates the pulse output format with negative
reactive energy output on pin E3 and the sign of the en-
ergy on E2. The E3 and E2 pulse output switching char-
acteristics are specified in Figure 2 on page 13.
PF = Power Factor
PulseRate = PulseRateE x (MCLK/K)/2048 [Hz]
VREFIN = Voltage at VREFIN pin [V]
With MCLK = 4.096 MHz, PF = 1 and default settings,
the pulses will have an average frequency equal to the
frequency specified by PulseRate when the input sig-
nals applied to the voltage and current channels cause
full-scale readings in the instantaneous voltage and cur-
rent registers. The maximum pulse frequency from the
E1 pin is (MCLK/K)/2048.
The pulse output frequency of E3 is directly proportional
to the reactive power calculated from the input signals.
To calculate the output frequency on E3, the following
transfer function can be utilized:
5.5.2 Apparent Energy Mode
Setting bit E2MODE = 1 in the Operational Mode Reg-
ister outputs apparent energy pulses on pin E2. Setting
bit E3MODE1:0 = 3 in the Operational Mode Register
outputs apparent energy pulses on pin E3. Figure 6 il-
lustrates the pulse output format with apparent energy
on E2 (E2MODE = 1 and E3MODE1:0 = 0)
VIN × VGAIN × IIN × IGAIN × PQ × PulseRate
FREQ = ---------------------------------------------------------------------------------------------------------------------------------
Q
2
VREFIN
FREQ = Average frequency of reactive energy E3 pulses [Hz]
Q
VIN = rms voltage across VIN+ and VIN- [V]
VGAIN = Voltage channel gain
IIN = rms voltage across IIN+ and IIN- [V]
IGAIN = Current channel gain
2
PQ = 1 – PF
E1
E2
E3
PulseRate = PulseRateE x (MCLK/K)/2048 [Hz]
VREFIN = Voltage at VREFIN pin [V]
With MCLK = 4.096 MHz, PF = 0 and default settings,
the pulses will have an average frequency equal to the
frequency specified by PulseRate when the input sig-
nals applied to the voltage and current channels cause
full-scale readings in the instantaneous voltage and cur-
rent registers. The maximum pulse frequency from the
E1 pin is (MCLK/K)/2048.
Figure 6. Apparent energy pulse outputs
The pulse output frequency of E2 (and/or E3) is directly
proportional to the apparent power calculated from the
input signals. Since apparent power is without reference
to an impedance phase angle, the following transfer
function can be utilized to calculate the output frequency
on E2 (and/or E3).
5.5.4 Voltage Channel Sign Mode
Setting bit E3MODE1:0 = 2 in the Operational Mode
Register outputs the sign of the voltage channel on pin
E3. Figure 7 illustrates the output format with voltage
channel sign on E3
VIN × VGAIN × IIN × IGAIN × PulseRate
FREQ = ------------------------------------------------------------------------------------------------------------------
S
2
VREFIN
FREQ = Average frequency of apparent energy E2 and/or E3 pulses [Hz]
S
VIN = rms voltage across VIN+ and VIN- [V]
VGAIN = Voltage channel gain
IIN = rms voltage across IIN+ and IIN- [V]
IGAIN = Current channel gain
PulseRate = PulseRateE x (MCLK/K)/2048 [Hz]
VREFIN = Voltage at VREFIN pin [V]
E1
E2
E3
Figure 7. Voltage Channel Sign Pulse outputs
DS678PP1
18
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