LM611IM National Semiconductor, LM611IM Datasheet - Page 13

• Manufacturer Part Number: LM611IM
• Description: Operational Amplifier (Op-Amp) IC
• Manufacturer: National Semiconductor

Specifications of LM611IM

• No. Of Amplifiers: 1
• Slew Rate: 0.7V/µs
• No. Of Pins: 14
• Operating Temperature Range: -40°C To +85°C
• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Amplifier Type: Operational
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Typical Performance Distributions
Application Information
VOLTAGE REFERENCE
Reference Biasing
The voltage reference is of a shunt regulator topology that
models as a simple zener diode. With current I
‘forward’ direction there is the familiar diode transfer func-
tion. I
voltage to be developed from cathode to anode. The applied
voltage to the cathode may range from a diode drop below
V
parallel protection diode, nominally 7V. A 6.3V reference with
V+ = 3V is allowed.
−
to the reference voltage or to the avalanche voltage of the
r
flowing in the reverse direction forces the reference
Voltage Reference Broad-Band
Noise Distribution
Noise Distribution
Op Amp Current
00922182
00922180
r
flowing in the
(Continued)
13
The reference equivalent circuit reveals how V
constant 1.2V by feedback, and how the FEEDBACK pin
passes little current.
To generate the required reverse current, typically a resistor
is connected from a supply voltage higher than the reference
voltage. Varying that voltage, and so varying I
effect with the equivalent series resistance of less than an
ohm at the higher currents. Alternatively, an active current
source, such as the LM134 series, may generate I
FIGURE 1. Voltages Associated with Reference
FIGURE 2. Reference Equivalent Circuit
(Current Source I
Noise Distribution
Op Amp Voltage
r
is External)
00922115
00922114
00922181
r
is held at the
r
, has small
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r
.