August 2000
LM611
Operational Amplifier and Adjustable Reference
General Description
Features
The LM611 consists of a single-supply op-amp and a pro-
grammable voltage reference in one space saving 8-pin
package. The op-amp out-performs most single-supply
op-amps by providing higher speed and bandwidth along
with low supply current. This device was specifically de-
signed to lower cost and board space requirements in trans-
ducer, test, measurement and data acquisition systems.
OP AMP
n Low operating current: 300 µA (op amp)
n Wide supply voltage range: 4V to 36V
n Wide common-mode range: V− to (V+−1.8V)
n Wide differential input voltage:
n Available in low cost 8-pin DIP
n Available in plastic package rated for Military
±
36V
Combining a stable voltage reference with a wide output
swing op-amp makes the LM611 ideal for single supply
transducers, signal conditioning and bridge driving where
large common-mode signals are common. The voltage refer-
ence consists of a reliable band-gap design that maintains
low dynamic output impedance (1Ω typical), excellent initial
tolerance (0.6%), and the ability to be programmed from
1.2V to 6.3V via two external resistors. The voltage refer-
ence is very stable even when driving large capacitive loads,
as are commonly encountered in CMOS data acquisition
systems.
Temperature Range Operation
REFERENCE
n Adjustable output voltage: 1.2V to 6.3V
n Tight initial tolerance available:
n Wide operating current range: 17 µA to 20 mA
n Reference floats above ground
±
0.6%
n Tolerant of load capacitance
Applications
n Transducer bridge driver
n Process and Mass Flow Control systems
n Power supply voltage monitor
n Buffered voltage references for A/D’s
™
As a member of National’s Super-Block family, the LM611
is a space-saving monolithic alternative to a multi-chip solu-
tion, offering a high level of integration without sacrificing
performance.
Connection Diagrams
DS009221-1
DS009221-2
™
Super-Block is a trademark of National Semiconductor Corporation.
© 2000 National Semiconductor Corporation
DS009221
www.national.com