LMP8358MA NSC [National Semiconductor], LMP8358MA Datasheet - Page 20

• Manufacturer Part Number: LMP8358MA
• Description: Zero-Drift, Programmable Instrumentation Amplifier with Diagnostics
• Manufacturer: NSC [National Semiconductor]

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Pin Name
SDO
SDI
SCK
CSB
VLSER
VHSER
Bit No
0
1
2
3
4
5
6
7
8
9
10
Table 4. LMP8358 Register Description, Serial Mode
Table 3. Function of Digital IO Pins, Serial Mode
Name
G0
G1
G2
COMP0
COMP1
COMP2
MUX0
MUX1
POL
SHDN
FILT
Description
Gain setting (LSB)
Gain setting
Gain setting (MSB)
Frequency compensation setting (LSB)
Frequency compensation setting
Frequency compensation setting (MSB)
Input multiplexer selection (LSB)
Input multiplexer selection (MSB)
Input polarity switch
Shutdown Enable
Enable filtering using external cap
Description
Serial Data Out
Serial Data In
Serial Clock
Chip Select
Negative Logic level
Positive Logic Level
20
Serial Control Interface Operation
The LMP8358 gain, bandwidth compensation, shutdown, in-
put options, and fault detection are controlled by an on board
programmable register. Data to be written into the control
register is first loaded into the LMP8358 via the serial inter-
face. The serial interface employs an 16-bit double-buffered
register for glitch-free transitions between settings. Data is
loaded through the serial data input, SDI. Data passing
through the shift register is output through the serial data out-
put, SDO. The serial clock, SCK controls the serial loading
process. All sixteen data bits are required to correctly program
the amplifier. The falling edge of CSB enables the shift reg-
ister to receive data. The SCK signal must be high during the
falling and rising edge of CSB. Each data bit is clocked into
the shift register on the rising edge of SCK. Data is transferred
from the shift register to the holding register on the rising edge
of CSB. Operation is shown in the SPI Timing Diagram.
The serial control pins can be connected in one of two ways
when two or more LMP8358s are used in an application.
Bit No
11
12
13
14
15
Name
PIN
CUR0
CUR1
CUR2
N/A
Description
Fault detection pin selection
Fault detection current setting (LSB)
Fault detection current setting
Fault detection current setting (MSB)
Unused, set to 0