CDB5460AU Cirrus Logic Inc, CDB5460AU Datasheet - Page 17

• Manufacturer Part Number: CDB5460AU
• Description: EVALUATION BOARD FOR CS5460A
• Manufacturer: Cirrus Logic Inc

Specifications of CDB5460AU

• Main Purpose: Power Management, Energy/Power Meter
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: CS5460A
• Primary Attributes: 1-Phase Current & Voltage Monitoring
• Secondary Attributes: Graphical User Interface, SPI™ & USB Interfaces
• Processor To Be Evaluated: CS5460A, C8051F320
• Interface Type: USB
• Operating Supply Voltage: 5 V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

complete isolation from the power lines. This isola-
tion is achieved using three transformers. One
transformer is a general-purpose voltage trans-
former, used to supply the on-board DC power to
the CS5460A. A second transformer is a high-pre-
cision, low-impedance voltage transformer (often
called a ‘potential transformer’) with very little
roll-off/phase delay, even at the higher harmonics.
A current transformer is then used to sense the line
current. A burden resistor placed across the sec-
ondary of the current transformer creates the cur-
rent-sense voltage signal, for the CS5460A’s
current channel inputs. Because the CS5460A is
DS487F4
Figure 6. Typical Connection Diagram (One-Phase 2-Wire, Direct Connect to Power Line)
N
R
2
To Service
120 VAC
R
1
L
470 nF
R
Shunt
500 Ω
R
R
** Refer to Input Filtering
*
* Refer to Input Protection
I-
*
I+
R
*
V-
+
100 µF
500
C
C
* *
* *
C
I-
I+
C
Ω
*
V+
* *
V-
*
0.1 µF
not directly connected to the power mains, isola-
tion is not required for the CS5460A’s digital inter-
face.
Figure 8 shows the CS5460A configured to mea-
sure power in a single-phase 3-wire system. In
many 3-wire residential power systems within the
United States, only the two Line terminals are
available (neutral is not available). Figure 9 shows
how the CS5460A can be configured to meter a
3-wire system when no neutral is available.
C * *
C * *
Idiff
0.1 µF
Vdiff
10
15
16
12
11
9
VIN+
VIN-
IIN-
IIN+
VREFIN
VREFOUT
VA+
NOTE: Current channel
input measures voltage
(just like voltage input).
14
VA-
CS5460A
13
10 Ω
DGND
CPUCLK
PFMON
RESET
XOUT
EOUT
SCLK
4
EDIR
VD+
SDO
XIN
SDI
INT
CS
3
5 k Ω
22
21
17
2
1
24
19
7
23
6
5
20
0.1 µF
Mech. Counter
Stepper Motor
2.5 MHz to
20 MHz
or
Optional
Source
10 k Ω
Clock
Interface
Serial
Data
CS5460A
17