THS4281 Datasheet, PDF (1/37 Pages) Texas Instruments – VERY LOW-POWER, HIGH-SPEED, RAIL-TO-RAIL INPUT AND OUTPUT VOLTAGE-FEEDBACK OPERATIONAL AMPLIFIER

THS4281
www.ti.com
SLOS432A – APRIL 2004 – REVISED NOVEMBER 2009
VERY LOW-POWER, HIGH-SPEED, RAIL-TO-RAIL INPUT AND OUTPUT
VOLTAGE-FEEDBACK OPERATIONAL AMPLIFIER
Check for Samples: THS4281
FEATURES
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•23 Very Low Quiescent Current: 750 μA (at 5 V)
• Rail-to-Rail Input and Output:
– Common-Mode Input Voltage Extends
400 mV Beyond the Rails
– Output Swings Within 150 mV From the
Rails
• Wide –3-dB Bandwidth at 5 V:
– 90 MHz at Gain = +1, 40 MHz at Gain = +2
• High Slew Rate: 35 V/μs
• Fast Settling Time (2-V Step):
– 78 ns to 0.1%
– 150 ns to 0.01%
• Low Distortion at Gain = +2, V_O = 2-V_PP, 5 V:
– –91 dBc at 100 kHz, –67 dBc at 1 MHz
• Input Offset Voltage: 2.5 mV (Max at +25°C)
• Output Current > 30 mA (10-Ω Load, 5 V)
• Low Voltage Noise of 12.5 nV/√Hz
• Supply Voltages: +2.7 V, 3 V, +5 V, ±5 V, +15 V
• Packages: SOT23, MSOP, and SOIC
APPLICATIONS
• Portable/Battery-Powered Applications
• High Channel Count Systems
• ADC Buffer
• Active Filters
• Current Sensing
DESCRIPTION
Fabricated using the BiCom-II process, the THS4281
is a low-power, rail-to-rail input and output,
voltage-feedback operational amplifier designed to
operate over a wide power-supply range of 2.7-V to
15-V single supply, and ±1.35-V to ±7.5-V dual
supply. Consuming only 750 μA with a unity gain
bandwidth of 90 MHz and a high 35-V/μs slew rate,
the THS4281 allows portable or other power-sensitive
applications to realize high performance with minimal
power. To ensure long battery life in portable
applications, the quiescent current is trimmed to be
less than 900 μA at +25°C, and 1 mA from –40°C to
+85°C.
The THS4281 is a true single-supply amplifier with a
specified common-mode input range of 400 mV
beyond the rails. This allows for high-side current
sensing applications without phase reversal
concerns. Its output swings to within 40 mV from the
rails with 10-kΩ loads, and 150 mV from the rails with
1-kΩ loads.
The THS4281 has a good 0.1% settling time of 78 ns,
and 0.01% settling time of 150 ns. The low THD of
–87 dBc at 100 kHz, coupled with a maximum offset
voltage of less than 2.5 mV, makes the THS4281 a
good match for high-resolution ADCs sampling less
than 2 MSPS.
The THS4281 is offered in a space-saving SOT23-5
package, a small MSOP-8 package, and the industry
standard SOIC-8 package.
V _BAT
500 W
I _RSENSE
0.2 W
500 W
Load
470 pF
470 pF
2.5 kW
VBAT
V _OUT = I _RSENSE
−
100 W
+ _{THS4281 10 nF}
2.5 kW
VBAT
+IN
ADS8320
−IN
VBAT/2
High-Side, Low Power Current-Sensing System
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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.
FilterPro is a trademark of Texas Instruments.
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All other trademarks are the property of their respective owners.
3
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 © 2004–2009, Texas Instruments Incorporated