NCP45491IMNGEVB
2
Table 3. EVALUATION BOARD DEFAULT CONNECTIONS
Connection
Connect To
0
Purpose
VBUS1 (banana)
12 V supply
Provides channel 1 and channel 3 bus voltages
VBUS2 (banana)
6 V supply
Provides channel 2 and channel 4 bus voltages
LOAD1 & GND (banana)
0.5 A load current (24
W
1W resistor)
Provides channel 1 load current
LOAD2 & GND (banana)
2 A load current (3
W
12 W resistor)
Provides channel 2 load current
LOAD3 & GND (banana)
0.5 A load (24
W
1W resistor)
Provides channel 3
LOAD4 & GND (banana)
2 A load current (3
W
12 W resistor)
Provides channel 4 load current
VCC & GND
3.3 V
Provides NCP45491 supply
MUX_SEL (sma)
3.3 V to 0 V signal generator
Channel mux select input
EN (sma/header)
3.3 V to 0 V signal generator or tied to GND
NCP45491 enable input. Active low
DIFF_OUT_P (sma)
Oscilloscope
Differential output (positive)
DIFF_OUT_N (sma)
Oscilloscope
Differential output (negative)
NOTES:
1. All connections to the board have an accompanying ground connection. Use all ground connections with the evaluation board being the
center of a star ground to avoid ground loops.
2. Connect to DIFF_OUT* signals with either 2 SMA to BNC cables to an oscilloscope (where the subtraction of the 2 signals give the differential
voltage), or connect to the DIFF_OUT* test loops with a twisted pair or differential probe. Connecting in this manner will mitigate noise via
EMI.
3. SH_INx inputs need to be driven to a voltage between VCC and 26 V, even for unused channels. Jumpers 1, 2, 5, and 8 provide a means
to connect unused channels to VCC. If a channel is not in use, the jumper should be switched to the VCC position and the SH_Ox jumper
should be removed to float the SH_Ox pin.
Table 4 below defines all default jumper connections and their purpose.
Table 4. DEFAULT JUMPER DEFINITION
Jumper
Default Setting
Function
J1
Shorted [1,2]
Connects channel 1 bus voltage. [2,3] connection sets bus voltage to 3.3 V
J2
Shorted [1,2]
Connects channel 1 bus voltage. [2,3] connection sets bus voltage to 3.3 V
J5
Shorted [1,2]
Connects channel 1 bus voltage. [2,3] connection sets bus voltage to 3.3 V
J8
Shorted [1,2]
Connects channel 1 bus voltage. [2,3] connection sets bus voltage to 3.3 V
J3
Shorted
SH_O2
J4
Shorted
SH_O1
J6
Shorted
SH_O3
J7
Shorted
SH_O4
J20
Shorted [1,2]
SKIP input connection
J21
Open
MODE_SEL input connection
J10
Open
SMD jumper that can be shorted to tie EN to GND
