ICL7611BCPA Intersil, ICL7611BCPA Datasheet - Page 5

• Manufacturer Part Number: ICL7611BCPA
• Description: Operational Amplifier (Op-Amp) IC
• Manufacturer: Intersil

Specifications of ICL7611BCPA

• No. Of Amplifiers: 1
• No. Of Pins: 8
• Amplifier Type: Operational
• Mounting Type: Through Hole
• Package / Case: 8-DIP

Application Information
Static Protection
All devices are static protected by the use of input diodes.
However, strong static fields should be avoided, as it is
possible for the strong fields to cause degraded diode
junction characteristics, which may result in increased input
leakage currents.
Latchup Avoidance
Junction-isolated CMOS circuits employ configurations which
produce a parasitic 4-layer (PNPN) structure. The 4-layer
structure has characteristics similar to an SCR, and under
certain circumstances may be triggered into a low impedance
state resulting in excessive supply current. To avoid this
condition, no voltage greater than 0.3V beyond the supply
rails may be applied to any pin. In general, the op amp
supplies must be established simultaneously with, or before
any input signals are applied. If this is not possible, the drive
circuits must limit input current flow to 2mA to prevent latchup.
Choosing the Proper I
The ICL7611 and ICL7612 have a similar I
which allows the amplifier to be set to nominal quiescent
currents of 10 A, 100 A or 1mA. These current settings
change only very slightly over the entire supply voltage
range. The ICL7611/12 have an external I
permitting user selection of quiescent current. To set the I
connect the I
I
I
voltage from V+ - 0.8 to V- +0.8 can be used.
I
NOTE: The output current available is a function of the quiescent
current setting. For maximum peak-to-peak output voltage swings
into low impedance loads, IQ of 1mA should be selected.
Output Stage and Load Driving Considerations
Each amplifiers’ quiescent current flows primarily in the
output stage. This is approximately 70% of the I
This allows output swings to almost the supply rails for
output loads of 1M , 100k , and 10k , using the output
stage in a highly linear class A mode. In this mode,
crossover distortion is avoided and the voltage gain is
maximized. However, the output stage can also be operated
in Class AB for higher output currents. (See graphs under
Typical Operating Characteristics). During the transition from
Class A to Class B operation, the output transfer
characteristic is non-linear and the voltage gain decreases.
Input Offset Nulling
Offset nulling may be achieved by connecting a 25K pot
between the BAL terminals with the wiper connected to V+.
At quiescent currents of 1mA and 100 A the nulling range
provided is adequate for all V
Q
Q
Q
= 10 A - I
= 100 A - I
= 1mA - I
Q
Q
Q
Q
pin to V-
pin to V+
terminal as follows:
pin to ground. If this is not possible, any
Q
OS
5
selections; however with
Q
Q
control terminal,
set-up scheme,
Q
settings.
ICL7611, ICL7612
Q
I
of V
Frequency Compensation
The ICL7611 and ICL7612 are internally compensated, and
are stable for closed loop gains as low as unity with
capacitive loads up to 100pF.
Extended Common Mode Input Range
The ICL7612 incorporates additional processing which
allows the input CMVR to exceed each power supply rail by
0.1V for applications where V
applications where V
in the positive direction, but may exceed the negative supply
rail by 0.1V in the negative direction (e.g., for V
the input CMVR would be +0.6V to -1.1V).
Operation At V
Operation at V
A and B grades only.
Output swings to within a few millivolts of the supply rails are
achievable for R
minimum and typically +0.9V to -0.7V at V
applications where greater common mode range is
desirable, refer to the description of ICL7612 above.
Typical Applications
The user is cautioned that, due to extremely high input
impedances, care must be exercised in layout, construction,
board cleanliness, and supply filtering to avoid hum and
noise pickup.
Note that in no case is I
chosen by the designer with regard to frequency response
and power dissipation.
NOTE:
Q
4. By using the ICL7612 in this application, the circuit will follow rail
V
IN
= 10 A, nulling may not be possible with higher values
to rail inputs.
OS
V
IN
100K
.
FIGURE 1. SIMPLE FOLLOWER (NOTE 4)
FIGURE 2. LEVEL DETECTOR (NOTE 4)
+5
SUPPLY
L
SUPPLY
1M . Guaranteed input CMVR is 0.6V
SUPP
ICL7612
+
= 1V is guaranteed at I
-
ICL7612
Q
+
-
shown. The value of I
= 1V
SUPP
+5
1.5V the input CMVR is limited
1M
1.5V. For those
SUPPLY
R
L
SUPPLY
Q
Q
V
TO CMOS OR
LPTTL LOGIC
10K
OUT
= 10 A for
must be
= 1V. For
V
OUT
= 1V,