CS5464_07 Datasheet, PDF (42/46 Pages) Cirrus Logic – Three-channel, Single-phase Power/Energy IC

CS5464
11. BASIC APPLICATION CIRCUITS
Figure 14 shows the CS5464 configured to measure
power in a single-phase, 2-wire system while operating
in a single-supply configuration. In this diagram, a shunt
resistor is used to sense the line current and a voltage
divider is used to sense the line voltage. In this type of
shunt-resistor configuration, the common-mode level of
the CS5464 must be referenced to the line side of the
power line. This means that the common-mode poten-
tial of the CS5464 will track the high-voltage levels, as
well as low-voltage levels, with respect to earth ground.
Isolation circuitry is required when an earth-ground-ref-
erenced communication interface is connected. A cur-
rent transformer (CT) is connected to the return line
current, which implements the tamper detection circuit.
5 kW
10 kW
L2
LINE
VOLTAGE
R₂
R₁
CT
LOAD
L1
500 W
1uF
R _V-
R _I-
R_Shunt
R _I+
½ R _Burden
½ R _Burden
500 W
10 W
470µF
0.1µF
18
VA+
0.1 µF
3
VD+
CS5464
9 _VIN+
C_V+
C_Vdiff
21
PFMON
CPUCLK ²
XOUT ¹
4.096 MHz
C_V-
C _I-
C _I+
R_I-
C _I-
10 _VIN-
19 _IIN-
C _Idiff
20 _IIN+
15
IIN2-
C _Idiff
XIN ²⁸
23
RESET
CS ⁷
SDI ²⁷
SDO ⁶
SCLK ⁵
INT ²⁴
E2 ²⁶
E1 ²⁵
Optional
Clock
Source
Serial
Data
Interface
C _I+
R_I+
16 _IIN2+
Pulse Output
Counter
0.1µF
12 _VREFIN
11 _VREFOUT
AGND
TEST1 ¹³
TEST2 ¹⁴
DGND
17
4
Figure 14. Typical Connection Diagram (Single-phase, 2-wire – Direct Connect to Power Line)
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DS682F1