©
Semiconductor Components Industries, LLC, 2018
December, 2018
−
Rev. 0
1
Publication Order Number:
EVBUM2592/D
NCP45491PMNGEVB
NCP45491 Paired Mode
Evaluation Board User's
Manual
Introduction
This user’s manual provides detailed information
regarding the configuration and use of the
NCP45491PMNGEVB evaluation board. The evaluation
board serves as a demonstration of NCP45491 general
functionality for
dual
mode chip mode featuring power
monitoring of 6 channels. The evaluation board also
provides a means of quick prototyping for specific
applications.
Features
•
2 NCP45491 Connected in Paired Mode
•
Connectors for 6 High Current Loads and 3 Separate Bus
Voltage Supplies
•
Configuration Options for Shunt Current and Bus Voltage
Gain Settings
•
Appropriate Test Points for Easy Evaluation
Quick Start
Recommended Equipment
Before beginning, the following equipment is needed:
•
4 DC Power Supplies (3.3 V VCC Supply, 12 V Bus
Voltage, 6 V Bus Supply, 8 V Bus Supply)
•
6 DC loads (Up to at Least 2 A)
•
1 Function Generator
•
1 Oscilloscope
•
1 Digital Multi-meter
•
SMA to BNC Cables Recommended for Connection to
DIFF_OUTN, DIFF_OUTP, and MUX_SEL
NOTE: Bus voltage supplies need to be capable of
sourcing load currents times 2 since each supply
sources 2 loads on the default setup.
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 2 bus voltage inputs. VBUS2 ties to
both channel 3 and channel 4 bus voltage inputs. VBUS3 ties
to both channel 5 and channel 6 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 (VBUS1)
12 V
1/60 V/V
3 (VBUS2)
6 V
1/30 V/V
4 (VBUS2)
6 V
1/30 V/V
5 (VBUS3)
8 V
1/40 V/V
6 (VBUS3)
8 V
1/40 V/V
Table 2. SHUNT CURRENT SETUP
Channel
Shunt Current
Target
Shunt Gain
Default Setting
Load 1
1 A
400 mV/A
Load 2
0.5 A
400 mV/A
Load 3
1 A
400 mV/A
Load 4
0.5 A
400 mV/A
Load 5
1 A
400 mV/A
Load 6
0.5 A
400 mV/A
The specific resistor configuration populated on the board
facilitates 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
×
Channel Bus Divider
×
2
•
For Load Current:
Diff Output = Load Current
×
Channel Shunt Gain
×
2
The output for each channel is calculated as follows:
Diff Output
+
Bus Voltage
R4
R4
)
R3
2
(eq. 1)
The channel shunt current gain is calculated as follows:
Diff Output
+
I
load
R2
R
sense
R1
2
(eq. 2)
EVAL BOARD USER’S MANUAL
