OPA861_15 Datasheet, PDF (1/32 Pages) Texas Instruments – Wide Bandwidth Operational Transconductance Amplifier (OTA)

OPA861
www.ti.com
SBOS338G – AUGUST 2005 – REVISED MAY 2013
Wide Bandwidth
Operational Transconductance
Amplifier (OTA)
Check for Samples: OPA861
FEATURES
1
• Wide Bandwidth (80MHz, Open-Loop, G = +5)
• High Slew Rate (900V/µs)
• High Transconductance (95mA/V)
• External I_Q-Control
• Low Quiescent Current (5.4mA)
APPLICATIONS
• Video/Broadcast Equipment
• Communications Equipment
• High-Speed Data Acquisition
• Wideband LED Drivers
• Control Loop Amplifiers
• Wideband Active Filters
• Line Drivers
DESCRIPTION
The OPA861 is a versatile monolithic component
designed for wide-bandwidth systems, including high
performance video, RF and IF circuitry. The OPA861
is a wideband, bipolar operational transconductance
amplifier (OTA).
The OTA or voltage-controlled current source can be
viewed as an ideal transistor. Like a transistor, it has
three terminals—a high impedance input (base), a
low-impedance input/output (emitter), and the current
output (collector). The OPA861, however, is self-
biased and bipolar. The output collector current is
zero for a zero base-emitter voltage. AC inputs
centered about zero produce an output current, which
is bipolar and centered about zero. The
transconductance of the OPA861 can be adjusted
with an external resistor, allowing bandwidth,
quiescent current, and gain trade-offs to be
optimized.
Used as a basic building block, the OPA861
simplifies the design of AGC amplifiers, LED driver
circuits for fiber optic transmission, integrators for fast
pulses, fast control loop amplifiers and control
amplifiers for capacitive sensors, and active filters.
The OPA861 is available in SO-8 and SOT23-6
surface-mount packages.
R
C₁
R
V _IN
V_OUT
C₂
Low−Pass Negative Impedance Converter (NIC) Filter
0
−10
−20
−30
−40
20kHz
−50 _{Low−Pass Filter}
−60
10MHz
Low−Pass Filter
−70
−80
1k
10k 100k
1M
10M 100M 1G
Frequency (Hz)
Frequency Response of 20kHz and 10MHz
Low−Pass NIC Filters
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005–2013, Texas Instruments Incorporated