Analog Section; Figure 2. Voltage Channel - Low-Voltage Input - Cirrus Logic CDB5490U Manual

1.3

Analog Section

The analog section of the CDB5490U is highly configurable. Onboard signal conditioning options for the
voltage and current channels enable most applications to interface directly to the sensors. The following
two sections define the voltage and current channel configurations.
1.3.1 Voltage Sensor Connection
There are three input signal options for the voltage channel input (VIN±): an external low-voltage signal
(via screw terminals or XLR connections), high-voltage line inputs, or GND. Figure 1 illustrates the options
available.
High-Voltage
The CDB5490U evaluation board provides screw-type terminals (J3) or XLR connectors (J30) to connect
low-voltage input signals to the voltage channel (see Figure 2). The screw terminals are labeled as
VIN+ / VIN-. An R-C network at the channel input provides a simple, configurable anti-alias filter. By in-
stalling jumpers on J6 to position VIN+ and J11 to position VIN-, the input voltage signal is supplied from
the screw terminals or XLR connections.
250 mVp
The CDB5490U evaluation board provides screw-type terminals (J4) to connect a high-voltage line input.
By installing jumpers on J6 to position LINE and J11 to position GND, the input voltage signal is supplied
from the high-voltage input. Extreme care should be used when connecting high-voltage signals to the
CDB5490U evaluation board (see Figure 3).
6
Table 1. Voltage Channel Input Signal Selection
INPUT Description
Selects External
VIN± Low-voltage Fully
Differential Signal
Selects External
VIN± Low-voltage Sin-
gle-ended Signal
Selects Grounding
GND
the Input
Selects External
High-voltage AC
Line
Line Signal
CDB5490U
J3
VIN+
VIN-
Figure 2. Voltage Channel — Low-voltage Input
J11
O

VIN- VIN-
O O
GND VIN-
(Default)
O

VIN- VIN-
O O
GND VIN-
O

VIN- VIN-
O O
GND
VIN-
 O
VIN- VIN-
O O
GND
VIN-
J45
J6
C4
0.027UF
C9
0.027UF
J11
CDB5490U
J6
O
 
GND VIN+
O O
Line VIN+
O O
VIN+ VIN+
(Default)
O
 
GND VIN+
O O
Line VIN+
O O
VIN+ VIN+
O
 
GND
VIN+
O O
Line
VIN+
O O
VIN+
VIN+
  O
GND
VIN+
O O
Line
VIN+
O O
VIN+
VIN+
VIN+
CS5490
VIN-
DS923DB5