LTC6102IMS8#PBF Linear Technology, LTC6102IMS8#PBF Datasheet - Page 15

• Manufacturer Part Number: LTC6102IMS8#PBF
• Description: IC AMP CURRENT SENSE 8-MSOP
• Manufacturer: Linear Technology

Specifications of LTC6102IMS8#PBF

• Amplifier Type: Current Sense
• Number Of Circuits: 1
• Gain Bandwidth Product: 200kHz
• Current - Input Bias: 60pA
• Voltage - Input Offset: 3µV
• Current - Supply: 420µA
• Current - Output / Channel: 1mA
• Voltage - Supply, Single/dual (±): 4 V ~ 60 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• No. Of Amplifiers: 1
• Input Bias Current: 3nA
• Output Current Per Channel: 1mA
• Input Offset Voltage: 10µV
• Bandwidth: 200kHz
• Supply Voltage Range: 4V To 60V
• Supply Current: 650µA
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Output Type: -
• -3db Bandwidth: -
• Slew Rate: -

APPLICATIONS INFORMATION
Ideally, the circuit output is:
In this case, the only error is due to resistor mismatch,
which provides an error in gain only.
Output Error, E
Voltage, V
The DC offset voltage of the amplifi er adds directly to
the value of the sense voltage, V
small (3μV typ) and may be ignored for reasonable values
of R
offset can be calibrated in the system due to its extremely
low drift.
Output Error, E
I
The input bias current of the LTC6102 is vanishingly small.
However, for very high resolution, or at high temperatures
where I
signifi cant.
The bias current I
internal op amp. I
Since I
B
(+) and I
E
E
E
Figure 4. LTC6102 Output Error Due to Typical Input Offset
vs Input Voltage
V
OUT(VOS)
OUT(IBIAS)
OUT(IBIAS)
OUT
IN
. See Figure 4. For very high dynamic range, this
B
B
(+) ≈ I
=
0.0001
increases due to leakage, the current may be
0.001
V
B
OS
0.01
100
0.1
(–)
SENSE
10
0.00001 0.0001
1
= V
= R
≈ –R
B
OUT
OUT
(–) = I
OS
B
OUT
B
, Due to the Amplifi er DC Offset
, Due to the Bias Currents,
•
(+) fl ows into the positive input of the
(–) fl ows into the negative input.
OUT
• (R
R
V
R
IN
((I
OUT
BIAS
IN
= 10 V
INPUT VOLTAGE (V)
• I
OUT
B
(+) • (R
0.001
BIAS
;
, if R
FOR A 500
V
ERROR DUE TO V
V
/R
IN
SENSE
= 100mV, I
IN
SENSE
)
0.01
SENSE
SENSE
=
SHUNT
SHUNT
R
<< R
OS
0.1
SENSE
/R
. This error is very
IS 6mA
= 200A
IN
6102 F04
IN
) – I
then,
•
1
I
SENSE
B
(–))
For instance if I
error is –10μV.
Note that in applications where R
a voltage offset in R
I
R
external resistor R
shown in Figure 5. Under both conditions:
Adding R
range of the circuit. For less sensitive designs, R
not necessary.
Clock Feedthrough, Input Bias Current
The LTC6102 uses auto-zeroing circuitry to achieve an
almost zero DC offset over temperature, sense voltage,
and power supply voltage. The frequency of the clock
used for auto-zeroing is typically 10kHz. The term clock
feedthrough is broadly used to indicate visibility of this
clock frequency in the op amp output spectrum. There are
typically two types of clock feedthrough in auto zeroed
amps like the LTC6102.
The fi rst form of clock feedthrough is caused by the
settling of the internal sampling capacitor and is input
referred; that is, it is multiplied by the internal loop gain
B
IN
(–) and E
E
, the bias current error can be similarly reduced if an
R
OUT(IBIAS)
SENSE
LOAD
V
+
IN
LTC6102-1/LTC6102HV
OUT(IBIAS)
+
R
R
Figure 5. Second Input R Minimizes
Error Due to Input Bias Current
as described will maximize the dynamic
IN
IN
= ± R
–
+
BIAS
+IN
V
–
IN
R
OUT
IN
LTC6102
(+) = (R
is 1nA and R
SENSE
+
≈ 0. In applications where R
=
R
+
• I
IN
–
OS
–
R
that cancels the error due to
SENSE
IN
; I
–
OS
– R
SENSE
= I
SENSE
OUT
B
(+) – I
–INS
V
OUT
–INF
V
REG
+
≈ R
6102 F05
is 10k, the output
LTC6102
) is connected as
IN
R
B
, I
OUT
(–)
B
(+) causes
V
OUT
0.1μF
15
SENSE
IN
6102fd
+
is
<