LMP8602MA/NOPB National Semiconductor, LMP8602MA/NOPB Datasheet - Page 15

• 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

ADDITIONAL SECOND ORDER LOW PASS FILTER
The LMP8602/LMP8602Q/LMP8603/LMP8603Q has a third
order Butterworth low-pass characteristic with a typical band-
width of 60 kHz integrated in the preamplifier stage of the part.
The bandwidth of the output buffer can be reduced by adding
a capacitor on the A1 pin to create a first order low pass filter
with a time constant determined by the 100 kΩ internal resis-
tor and the external filter capacitor.
When the corner frequency of the additional filter is much
lower than 60 kHz, the transfer function of the described am-
plifier can be written as:
Where K
the buffer amplifier.
The above equation can be written in the normalized frequen-
cy response for a 2
The Cutt-off frequency ω
cut-off frequency in Hz) is given by:
And the quality factor of the filter is given by:
1
equals the gain of the preamplifier and K
nd
order low pass filter:
o
in rad/sec (divide by 2
FIGURE 2. Second Order Low Pass Filter
K1 = 10, K2 = 5 for LMP8602, K2 = 10 for LMP8603
π
to get the
2
that of
15
It is also possible to create an additional second order Sallen-
Key low pass filter as shown in
components R
100 kΩ resistor R
pass filter characteristic.
For any filter gain K > 1x, the design procedure can be very
simple if the two capacitors are chosen to in a certain ratio.
Inserting this in the above equation for Q results in:
Which results in:
In this case, given the predetermined value of R1 = 100 kΩ
(the internal resistor), the quality factor is set solely by the
value of the resistor R
2
, C
1
, this circuit creates a second order low-
1
2
and C
.
2
. Together with the internal
30083455
Figure 2
by adding external
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