Document
OPA657
OPA 657
SBOS197B – DECEMBER 2001 – REVISED MAY 2004
1.6GHz, Low-Noise, FET-Input OPERATIONAL AMPLIFIER
FEATURES
q q q q q HIGH GAIN BANDWIDTH PRODUCT: 1.6GHz HIGH BANDWIDTH 275MHz (G = +10) LOW INPUT OFFSET VOLTAGE: ±0.25mV LOW INPUT BIAS CURRENT: 2pA LOW INPUT VOLTAGE NOISE: 4.8nV/ Hz
DESCRIPTION
The OPA657 combines a high gain bandwidth, low distor-tion, voltage-feedback op amp with a low voltage noise JFET-input stage to offer a very high dynamic range amplifier for high precision ADC (Analog-to-Digital Converter) driving or wideband transimpedance applications. Photodiode applications will see improved noise and bandwidth using this decompensated, high gain bandwidth amplifier. Very low level signals can be significantly amplified in a single OPA657 gain stage with exceptional bandwidth and accuracy. Having a high 1.6GHz gain bandwidth product will give > 10MHz signal bandwidths up to gains of 160V/V (44dB). The very low input bias current and capacitance will support this performance even for relatively high source impedances. Broadband photodetector applications will benefit from the low voltage noise JFET inputs for the OPA657. The JFET input contributes virtually no current noise while for broadband applications, a low voltage noise is also required. The low 4.8nV/ Hz input voltage noise will provide exceptional input sensitivity for higher bandwidth applications. The example shown below will give a total equivalent input noise current of 1.8pA/ Hz over a 10MHz bandwidth.
q HIGH OUTPUT CURRENT: 70mA q FAST OVERDRIVE RECOVERY
APPLICATIONS
q q q q q WIDEBAND PHOTODIODE AMPLIFIER WAFER SCANNING EQUIPMENT ADC INPUT AMPLIFIER TEST AND MEASUREMENT FRONT END HIGH GAIN PRECISION AMPLIFIER
200kΩ TRANSIMPEDANCE BANDWIDTH 116 10MHz Bandwidth
RELATED OPERATIONAL AMPLIFIER PRODUCTS
SLEW VOLTAGE VS BW RATE NOISE (V) (MHz) (V/µS) (nV/√HZ) AMPLIFIER DESCRIPTION 200 400 500 16 180 300 290 170 55 100 5.80 6 7 4.5 5.4 Unity-Gain Unity-Gain Unity-Gain Unity-Gain Unity-Gain Stable Stable Stable Stable Stable CMOS FET-Input FET-Input FET-Input FET-Input
Transimpedance Gain (dB)
106
DEVICE
96
86
OPA355 +5 OPA655 ±5 OPA656 ±5 OPA627 ±15 THS4601 ±15
76
0.1pF 200kΩ
66 100kHz
1MHz Frequency
10MHz
50MHz
λ (12pF)
OPA657
VO
–Vb
Wideband Photodiode Transimpedance Amplifier
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.
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.
Copyright © 2001-2004, Texas Instruments Incorporated
www.ti.com
PACKAGE/ORDERING INFORMATION(1)
PACKAGE DESIGNATOR(1) D SPECIFIED TEMPERATURE RANGE –40°C to +85°C PACKAGE MARKING OPA657U ORDERING NUMBER(2) OPA657U OPA657U/2K5 OPA657UB OPA657UB/2K5 OPA657N/250 OPA657N/3K OPA657NB/250 OPA657NB/3K TRANSPORT MEDIA, QUANTITY Rails, 100 Tape and Reel, 2500 Rails, 100 Tape and Reel, 2500 Tape and Reel, 250 Tape and Reel, 3000 Tape and Reel, 250 Tape and Reel, 3000
PRODUCT OPA657U
PACKAGE-LEAD SO-8 Surface Mount
"
OPA657UB
"
SO-8 Surface Mount
"
D
"
–40°C to +85°C
"
OPA657UB
"
OPA657N
"
SOT23-5
"
DBV
"
–40°C to +85°C
"
A57
"
OPA657NB
"
SOT23-5
"
DBV
"
–40°C to +85°C
"
A57
"
"
"
"
"
NOTES: (1) For the most current package and ordering infromation, see the Package Option Addendum located at the end of this data sheet.
ABSOLUTE MAXIMUM RATINGS(1)
Supply Voltage ................................................................................. ±6.5V Internal Power Dissipation ........................... See Thermal Characteristics Differential Input Voltage ..................................................................... ±VS Input Voltage Range ............................................................................ ±VS Storage Temperature Range ......................................... –40°C to +125°C Lead Temperature ......................................................................... +260°C Junction Temperature (TJ ) ........................................................... +175°C ESD Rating (Human Body Model) .................................................. 2000V (Machine Model) ............................................................ 200V NOTE: (1) Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those specified is not implied.
ELECTROSTATIC DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled.