CDB5461AU Cirrus Logic Inc, CDB5461AU Datasheet - Page 19

• Manufacturer Part Number: CDB5461AU
• Description: Eval Bd Sngl Phase Power/Energy
• Manufacturer: Cirrus Logic Inc

Specifications of CDB5461AU

• Main Purpose: Power Management, Energy/Power Meter
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: CS5461A
• Primary Attributes: 1-Phase, Energy-to-Frequency Output
• Secondary Attributes: GUI, USB, SPI, Microwire Interfaces
• Processor To Be Evaluated: CS5461A, C8051F320
• Interface Type: USB
• Operating Supply Voltage: 5 V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant, Contains lead / RoHS non-compliant
• Other names: 598-1552

EXAMPLE #2:
The required number of pulses per unit energy present
on E1 is specified to be 500 pulses per kWhr, given that
the line voltage is 250 Vrms and the line current is
20 Arms. In such a situation, the stated line voltage and
current do not determine the appropriate PulseRateE
setting. To achieve full-scale readings in the instanta-
neous voltage and current registers, a 250 mV, DC-lev-
el signal is applied to the channel inputs.
As in example #1, the voltage and current channel gains
are 10x, and the voltage level at the channel inputs will
be 150 mV rms when the levels on the power lines are
250 V rms
500 pulse-per-kW Hr
PulseRateE
following equation:
Therefor, the PulseRateE
1.929 Hz. The PulseRateE
a frequency of exactly 1.929 Hz. The closest setting is
0x00003E = 1.9375 Hz.
To improve the accuracy, either gain register can be
programmed to correct for the round-off error. This val-
ue would be calculated as
If
PulseRateE
factor of:
Therefore if (MCLK/K) = 3.05856 MHz the value of
PulseRateE
5.5 Voltage Sag-detect Feature
Status bit VSAG in the Status Register, indicates a volt-
age sag occurred in the power line voltage. For a volt-
age sag condition to be identified, the absolute value of
the instantaneous voltage must be less than the voltage
DS661F2
PulseRateE 1 2
(MCLK/K)
Vgn or Ign
PulseRateE
,
1,2
1,2
1,2
and
=
Register setting is determined using the
Register must be scaled by a correction
Register is
500pulses
----------------------------- -
is
4.096MHz
--------------------------- -
(MCLK/K)
=
kWHr
1 2
20 A rms.
PulseRateE
-----------------------------------
,
not
1.929
=
-------------------- -
3.05856
×
×
4.096
----------------
3600s
equal
1,2
per
1Hr
PulseRateE 1 2
1,2
≅
Register is approximately
Register cannot be set to
×
×
1.00441
In
------------------ -
1000W
1.929Hz
1kW
to
unit-energy,
order
,
×
=
4.096 MHz,
------------------------ -
⎛
⎝
≅
250mV
150mV
-------------------
250V
0x404830
2.583Hz
to
⎞
⎠
×
------------------------ -
⎛
⎝
achieve
250mV
150mV
-------------------
20A
the
the
1,2
⎞
⎠
sag level for more than half of the voltage sag duration
(see
To activate Voltage Sag detect, a voltage sag level must
be specified in the Voltage Sag Level Register
(VSAG
ified in the Voltage Sag Duration Register
(VSAG
average of the absolute instantaneous voltage. Voltage
sag duration is specified in terms of ADC cycles.
5.6 No Load Threshold
The CS5461A includes the LoadIntv (No Load Detec-
tion Interval) register and the LoadMin register to imple-
ment the no load threshold function. When the
accumulated energy measured within the time defined
by the LoadIntv register does not reach the value in the
LoadMin register, the pulse outputs will be disabled.
5.7 On-chip Temperature Sensor
The on-chip temperature sensor is designed to assist in
characterizing the measurement element over a desired
temperature range. Once a temperature characteriza-
tion is performed, the temperature sensor can then be
utilized to assist in compensating for temperature drift.
Temperature measurements are performed during con-
tinuous conversions and stored in the Temperature
Register. The Temperature Register (T) default is Cel-
sius scale (
and Temperature Offset Register (T
ues allowing for temperature scale conversions.
The temperature update rate is a function of the number
of ADC samples. With MCLK = 4.096 MHz and K = 1
the update rate is:
Figure
Level
Duration
), and a voltage sag duration must be spec-
o
Figure 7. Voltage Sag Detect
7).
C). The Temperature Gain Register (T
). The voltage sag level is specified as the
---------------------------------------- -
(MCLK/K)/1024
2240 samples
Duration
=
0.56 sec
off
) are constant val-
CS5461A
Level
gain
19
)