©
Semiconductor Components Industries, LLC, 2018
August, 2018
−
Rev. 0
1
Publication Order Number:
EVBUM2577/D
NCP45491IMNGEVB
NCP45491 Evaluation Board
User's Manual
Introduction
This user’s manual provides detailed information
regarding the configuration and use of the
NCP45491IMNGEVB Evaluation board. The evaluation
board serves as a demonstration of NCP45491 general
functionality for single chip mode featuring power
monitoring of 4 channels. The evaluation board also
provides a means of quick prototyping for specific
applications.
Features
•
NCP45491
•
Connectors for 4 High Current Supplies and Loads
•
Configuration Options for Shunt Current and Gain
Settings
•
Appropriate Test Loops for Easy Evaluations
QUICK START
Recommended Equipment
Before beginning, the following equipment is needed:
•
4 DC Power Supplies (2 capable of at least 7 V, 2 capable
of at least 13 V to support current evaluation board setup)
•
4 DC Loads (up to at least 2 A)
•
Function Generator
•
Oscilloscope
•
Digital Multi
−
meter
•
SMA to BNC Cables Recommended for Connection to
DIFF_OUTN, DIFF_OUTP, and MUX_SEL
Board Setup
The assembled evaluation board targets Bus Voltages and
Shunt Currents shown in Tables 1 and 2. VBUS1 ties to both
channel 1 and channel 3 bus voltage inputs. VBUS2 ties to
both channel 2 and channel 4 bus voltage inputs. Refer to the
schematic and layout diagrams found in
and
respectively as needed.
Table 1. BUS VOLTAGE SETUP
Channel
Target Bus Voltage
Bus Divider
1 (VBUS1)
12 V
1/60 V/V
2 (VBUS2)
6 V
1/30 V/V
3 (VBUS1)
12 V
1/60 V/V
4 (VBUS2)
6 V
1/30 V/V
Table 2. SHUNT CURRENT SETUP
Channel
Shunt Current
Shunt Gain
Load 1
0.5 A
400 mV/A
Load 2
5 A
40 mV/A
Load 3
0.5 A
400 mV/A
Load 4
5 A
40 mV/A
The specific resistor configuration populated on the board
facilitate these gain settings. The nominal differential
amplifier gain is 2 V/V. Therefore, the expected differential
output for any channels voltage or current can be calculated
as follows:
•
For Bus Voltage:
Diff Output
+
Bus Voltage
@
R4
R4
)
R3
@
2
(eq. 1)
•
For Load Current:
Diff Output = Load Current * Channel Shunt Gain * 2
Diff Output
+
I
Load
@
R2
)
R
sense
R1
@
2
(eq. 2)
These gain settings can be adjusted by changing the bus
divider resistors, and the shunt current network resistors as
desired.
Board Connections & Jumper Settings
The following board to bench equipment connections are
required for demonstration of 4 channel power monitoring.
Make all board connections with supplies and loads
disabled. Take adequate precautions when working with
high current and high voltage applications. Table 3 below
defines all default board connections and their purpose.
EVAL BOARD USER’S MANUAL
