OPA656
OPA656
www.ti.com
SBOS196G – DECEMBER 2001 – REVISED NOVEMBER 2008
Wideband, Unity-Gain Stable, FET-Input
OPERATIONAL AMPLIFIER
FEATURES
DESCRIPTION
● 500MHz UNITY-GAIN BANDWIDTH
The OPA656 combines a very wideband, unity-gain stable,
voltage-feedback op amp with a FET-input stage to offer an
ultra high dynamic-range amplifier for ADC (Analog-to-Digital
Converter) buffering and transimpedance applications. Extremely
low DC errors give good precision in optical applications.
● LOW INPUT BIAS CURRENT: 2pA
● LOW OFFSET AND DRIFT: ±0.25mV, ±2µV/°C
● LOW DISTORTION: 74dB SFDR at 5MHz
● HIGH OUTPUT CURRENT: 70mA
The high unity-gain stable bandwidth and JFET input allows
exceptional performance in high-speed, low-noise integrators.
● LOW INPUT VOLTAGE NOISE: 7nV/√Hz
The high input impedance and low bias current provided by
the FET input is supported by the ultra-low 7nV/√Hz input
voltage noise to achieve a very low integrated noise in
wideband photodiode transimpedance applications.
APPLICATIONS
● WIDEBAND PHOTODIODE AMPLIFIERS
● SAMPLE-AND-HOLD BUFFERS
● CCD OUTPUT BUFFERS
Broad transimpedance bandwidths are achievable given the
OPA656’s high 230MHz gain bandwidth product. As shown
below, a –3dB bandwidth of 1MHz is provided even for a high
1MΩ transimpedance gain from a 47pF source capacitance.
● ADC INPUT BUFFERS
● WIDEBAND PRECISION AMPLIFIERS
● TEST AND MEASUREMENT FRONT ENDS
RELATED OPERATIONAL AMPLIFIER PRODUCTS
SLEW VOLTAGE
VS BW RATE NOISE
DEVICE (V) (MHz) (V/µS) (nV/√HZ) AMPLIFIER DESCRIPTION
1pF
OPA355 +5 200
300
290
5.8
6
Unity-Gain Stable CMOS
OPA655 ±5 400
Unity-Gain Stable FET-Input
Gain of +7 Stable FET-Input
Unity-Gain Stable FET-Input
Unity-Gain Stable FET-Input
OPA657 ±5 1600 700
4.8
4.5
5.4
OPA627 ±15 16
THS4601 ±15 180
55
499kΩ
499kΩ
100
1MΩ TRANSIMPEDANCE BANDWIDTH
1MHz Bandwidth
130
120
110
100
90
VO
OPA656
λ
(47pF)
–Vb
Wideband Photodiode Transimpedance Amplifier
80
10kHz
100kHz
Frequency
1MHz
5MHz
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.
All trademarks are the property of their respective owners.
Copyright © 2001-2008, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
www.ti.com