National Semiconductor INA260, Руководство пользователя

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T2
T1
J1 J4
J2, J3
INA260
V
DUT
Supply
GND
A
0
,
A
1
I
2
C interface
V
BUS
IN+
IN-
INA260EVM-PDK Hardware
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10 SBOU180 – November 2016
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INA260EVM-PDK and Software Tutorial
2.2 INA260EVM PCB Description
Figure 5 depicts a block diagram of the INA260EVM PCB highlighting the power supplies, analog inputs,
and digital I/O signals.
Figure 5. INA260EVM Block Diagram
The EVM PCB requires minimal instrumentation to be operated. In fact, the only pieces of required
equipment not included in the kit are a (Windows
®
7) computer and an input current source. All other
inputs are supplied by the SM-USB-DIG board, via the 10-pin connector socket, J4. Table 3 lists the
pinout for J4.
(1)
When V
DUT
is Hi-Z, all digital I/Os are Hi-Z as well.
Table 3. Signal Definition of J4 on INA260EVM Board
Pin on J4 Signal Description
10 I2C_SCL I
2
C clock signal (SCL)
9 CTRL/MEAS4 GPIO: control output or measure input
8 I2C_SDA1 I
2
C data signal (SDA)
7 CTRL/MEAS5 GPIO: control output or measure input
6 SPI_DOUT1 SPI data output (MOSI)
5 V
DUT
Switchable DUT power supply: 3.3 V, 5 V, Hi-
Z (disconnected)
(1)
4 SPI_CLK SPI clock signal (SCLK)
3 GND Power return (GND)
2 SPI_CS1 SPI chip-select signal (CS)
1 SPI_DIN1 SPI data input (MISO)
2.2.1 EVM Power Supply
The INA260EVM PCB uses the V
DUT
and GND lines from the SM-USB-DIG (via J4) as the high and low
supply voltages for the INA260. As noted in Table 3 , the available supply voltages for V
DUT
are 5V and
3.3V. The EVM supply voltage is user-selectable through the GUI. The 1µF ceramic capacitor, C2, placed
in close proximity to the INA260 (U1) supply pin provides adequate decoupling to V
DUT
for power supply
rejection at higher frequencies.