LMP8602MA/NOPB National Semiconductor, LMP8602MA/NOPB Datasheet - Page 14

• Manufacturer Part Number: LMP8602MA/NOPB
• Description: IC AMP CURRENT SENSE 60V 8SOIC
• Manufacturer: National Semiconductor
• Series: LMP®r
• Type: Current Sense Amplifierr

Specifications of LMP8602MA/NOPB

• Amplifier Type: Current Sense
• Number Of Circuits: 1
• Slew Rate: 0.83 V/µs
• Gain Bandwidth Product: 60kHz
• Current - Input Bias: 0.04pA
• Voltage - Input Offset: 150µV
• Current - Supply: 1.1mA
• Current - Output / Channel: 48mA
• Voltage - Supply, Single/dual (±): 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• No. Of Amplifiers: 1
• Input Bias Current: 20nA
• Input Offset Voltage: 1mV
• Bandwidth: 60kHz
• Cmrr: 105dB
• Supply Voltage Range: 3V To 5.5V
• Supply Current: 1.3mA
• Rohs Compliant: Yes
• Number Of Channels: 1
• Number Of Elements: 2
• Power Supply Requirement: Single
• Common Mode Rejection Ratio: 80dB
• Voltage Gain Db: 34.02dB
• Single Supply Voltage (typ): 5V
• Dual Supply Voltage (typ): Not RequiredV
• Power Supply Rejection Ratio: 70dB
• Rail/rail I/o Type: No
• Single Supply Voltage (min): 3V
• Single Supply Voltage (max): 5.5V
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: SOIC N
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Output Type: -
• -3db Bandwidth: -
• Lead Free Status / Rohs Status: Compliant
• Other names: LMP8602MA

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Application Information
GENERAL
The LMP8602 and LMP8603 are fixed gain differential volt-
age precision amplifiers with a gain of 50x for the LMP8602,
and 100x for the LMP8603. The input common mode voltage
range is -22V to +60V when operating from a single 5V supply
or -4V to +27V input common mode voltage range when op-
erating from a single 3.3V supply. The LMP8602 and
LMP8603 are members of the LMP family and are ideal parts
for unidirectional and bidirectional current sensing applica-
tions. Because of the proprietary chopping level-shift input
stage the LMP8602 and LMP8603 achieve very low offset,
very low thermal offset drift, and very high CMRR. The
LMP8602 and LMP8603 will amplify and filter small differen-
tial signals in the presence of high common mode voltages.
The LMP8602/LMP8602Q/LMP8603/LMP8603Q use level
shift resistors at the inputs. Because of these resistors, the
LMP8602/LMP8602Q/LMP8603/LMP8603Q can easily with-
stand very large differential input voltages that may exist in
fault conditions where some other less protected high-perfor-
mance current sense amplifiers might sustain permanent
damage.
PERFORMANCE GUARANTIES
To guaranty the high performance of the LMP8602/LM-
P8602Q/LMP8603/LMP8603Q, all minimum and maximum
values shown in the parameter tables of this datasheet are
100% tested where all bold limits are also 100% tested over
temperature.
FIGURE 1. Theory of Operation
K2 = 5 for LMP8602, K2 = 10 for LMP8603
14
THEORY OF OPERATION
The schematic shown in
sentation of the internal operation of the LMP8602/
LMP8603.
The signal on the input pins is typically a small differential
voltage across a current sensing shunt resistor. The input
signal may appear at a high common mode voltage. The input
signals are accessed through two input resistors. The propri-
etary chopping level-shift current circuit pulls or pushes cur-
rent through the input resistors to bring the common mode
voltage behind these resistors within the supply rails. Subse-
quently, the signal is gained up by a factor of 10 (K1) and
brought out on the A1 pin through a trimmed 100 kΩ resistor.
In the application, additional gain adjustment or filtering com-
ponents can be added between the A1 and A2 pins as will be
explained in subsequent sections. The signal on the A2 pin is
further amplified by a factor (K2) which equals a factor of 5 for
the LMP8602 and a factor of 10 for the LMP8603. The output
signal of the final gain stage is provided on the OUT pin. The
OFFSET pin allows the output signal to be level-shifted to
enable bidirectional current sensing as will be explained be-
low.
Figure 1
30083405
gives a schematic repre-