range previously unattainable in a monolithic op amp.
Using a de-compensated voltage feedback architec-
ture with two internal gain stages, the OPA643 achieves
exceptionally low harmonic distortion over a wide
frequency range. The "classic" differential input pro-
vides all the familiar benefits of precision op amps,
such as bias current cancellation and very low invert-
ing current noise compared with wideband current
feedback op amps. High slew rate and open-loop gain,
along with low input noise and high output current
drive make the OPA643 ideal for very high dynamic
range requirements.
The high gain bandwidth product for the gain
≥
3
stable OPA643 makes it particularly suitable for
wideband transimpedance amplifiers and moderate gain
IF amplifier applications. External compensation
techniques may be used to apply the OPA643 at low
gains giving exceptionally low distortion and frequency
response flatness. Where unity gain stability with
comparable distortion performance is required, consider
the OPA642.
+5V
5kΩ
REFT
0.1µF
+5V
ADS805
Low Gain
Compensation
0.1µF
280Ω
2Vp-p
0.1µF
50Ω
47pF
–5V
806Ω
2.7pF
14pF
OPA643
Analog
Input
12-Bit
20MSPS
Measured
80dB SFDR
50Ω
Source
1Vp-p
10MHz
56.9Ω
402Ω
5kΩ
REFB
0.1µF
High Dynamic Range 20MSPS Digitizer
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111
NOTE: (1) Packages must be derated based on specified
θ
must be observed.
JA
.
PIN CONFIGURATION
Top View
NC
Inverting Input
Non-Inverting Input
–V
S1
1
2
3
4
8
7
6
5
DIP/SO-8
+V
S2(1)
+V
S1
Output
–V
S2(1)
Maximum T
J
ELECTROSTATIC
DISCHARGE SENSITIVITY
Electrostatic discharge can cause damage ranging from per-
formance degradation to complete device failure. Burr-Brown
Corporation recommends that all integrated circuits be handled
and stored using appropriate ESD protection methods.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet published speci-
fications.
SOT23-5
Output
1
5
+V
S
–V
S
Non-Inverting Input
2
3
4
Inverting Input
NOTE: (1) Making use of all four power supply pins is highly recommended,
although not required. Using these four pins, instead of just pins 4 and 7, will
lower the power supply impedance improving distortion.
PACKAGE/ORDERING INFORMATION
PACKAGE
DRAWING
NUMBER
(1)
182
182
331
331
006
006
TEMPERATURE
RANGE
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
PACKAGE
MARKING
(2)
OPA643U
OPA643UB
A43
A43B
OPA643P
OPA643PB
ORDERING
NUMBER
(3)
OPA643U
OPA643UB
OPA643N-250
OPA643N-3k
OPA643NB-250
OPA643NB-3k
OPA643P
OPA643PB
PRODUCT
OPA643U
OPA643UB
OPA643N
OPA643NB
OPA643P
OPA643PB
PACKAGE
SO-8 Surface Mount
SO-8 Surface Mount
5-pin SOT23-5
5-pin SOT23-5
8-Pin Plastic DIP
8-Pin Plastic DIP
NOTES: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book. (2) The “B” grade of the SO-8 and
DIP packages will be marked with a “B” by pin 8. The “B” grade of the SOT23-5 will be marked with a “B” near pins 3 and 4. (3) The SOT23-5 is only available on a 7"
tape and reel (e.g. ordering 250 pieces of “OPA643N-250” will get a single 250 piece tape and reel. Ordering 3000 pieces of “OPA643N-3k” will get a single 3000 piece
tape and reel). Please refer to Appendix B of Burr-Brown IC Data Book for detailed Tape and Reel Mechanical information.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.