AD8045

Manufacturer Part NumberAD8045
Description3 nV/?Hz Ultralow Distortion Voltage Feedback High Speed Amplifier
ManufacturerAnalog Devices
AD8045 datasheet
 

Specifications of AD8045

-3db Bandwidth1GHzSlew Rate1350V/µs
Vos200µVIb2µA
# Opamps Per Pkg1Input Noise (nv/rthz)3nV/rtHz
Vcc-vee3.3V to 12VIsy Per Amplifier19mA
PackagesCSP,SOIC  
1
Page 1
2
Page 2
3
Page 3
4
Page 4
5
Page 5
6
Page 6
7
Page 7
8
Page 8
9
Page 9
10
Page 10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Page 1/24

Download datasheet (662Kb)Embed
Next
FEATURES
Ultralow distortion
SFDR
−101 dBc @ 5 MHz
−90 dBc @ 20 MHz
−63 dBc @ 70 MHz
Third-order intercept
43 dBm @ 10 MHz
Low noise
3 nV/√Hz
3 pA/√Hz
High speed
1 GHz, −3 dB bandwidth (G = +1)
1350 V/µs slew rate
7.5 ns settling time to 0.1%
Standard and low distortion pinout
Supply current: 15 mA
Offset voltage: 1.0 mV max
Wide supply voltage range: 3.3 V to 12 V
GENERAL DESCRIPTION
The AD8045 is a unity gain stable voltage feedback amplifier
with ultralow distortion, low noise, and high slew rate. With a
spurious-free dynamic range of −90 dBc @ 20 MHz, the
AD8045 is an ideal solution in a variety of applications,
including ultrasound, ATE, active filters, and ADC drivers.
ADI’s proprietary next generation XFCB process and innovative
architecture enables such high performance amplifiers.
The AD8045 features a low distortion pinout for the LFCSP,
which improves second harmonic distortion and simplifies the
layout of the circuit board.
The AD8045 has 1 GHz bandwidth, 1350 V/µs slew rate, and
settles to 0.1% in 7.5 ns. With a wide supply voltage range (3.3 V
to 12 V) and low offset voltage (200 µV), the AD8045 is an ideal
candidate for systems that require high dynamic range, preci-
sion, and high speed.
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
3 nV/√Hz Ultralow Distortion,
High Speed Op Amp
APPLICATIONS
Instrumentation
IF and baseband amplifiers
Active filters
ADC drivers
DAC buffers
CONNECTION DIAGRAMS
NC
1
8
FEEDBACK
2
7
–IN
3
6
+IN
4
5
Figure 1. 8-Lead AD8045 LFCSP (CP-8)
1
8
FEEDBACK
–IN
2
7
+IN
3
6
–V
4
5
S
Figure 2. 8-Lead AD8045 SOIC/EP (RD-8)
The AD8045 amplifier is available in a 3 mm × 3 mm LFCSP
and the standard 8-lead SOIC. Both packages feature an
exposed paddle that provides a low thermal resistance path to
the PCB. This enables more efficient heat transfer, and increases
reliability. The AD8045 works over the extended industrial
temperature range (−40°C to +125°C).
–20
G = +1
V
= ±5V
–30
S
V
= 2V p-p
OUT
R
= 1kΩ
L
–40
R
= 100Ω
S
–50
–60
–70
–80
HD3 LFCSP
–90
–100
–110
–120
0.1
1
10
FREQUENCY (MHz)
Figure 3. Harmonic Distortion vs. Frequency for Various Packages
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703
© 2004 Analog Devices, Inc. All rights reserved.
AD8045
+V
S
OUTPUT
NC
–V
S
NC
+ V
S
OUTPUT
NC
HD2 LFCSP
100
www.analog.com

AD8045 Summary of contents

  • Page 1

    ... The AD8045 has 1 GHz bandwidth, 1350 V/µs slew rate, and settles to 0.1% in 7.5 ns. With a wide supply voltage range (3 and low offset voltage (200 µV), the AD8045 is an ideal candidate for systems that require high dynamic range, preci- sion, and high speed. ...

  • Page 2

    ... AD8045 TABLE OF CONTENTS Specifications with ±5 V Supply ..................................................... 3 Specifications with +5 V Supply ..................................................... 4 Absolute Maximum Ratings............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Pin Configurations and Function Descriptions ........................... 6 Typical Performance Characteristics ............................................. 7 Circuit Configurations................................................................... 16 Wideband Operation ................................................................. 16 Theory of Operation ...................................................................... 17 Frequency Response................................................................... 17 DC Errors .................................................................................... 17 Output Noise............................................................................... 18 REVISION HISTORY 9/04—Data Sheet Changed from Rev Rev. A Changes to Features ...

  • Page 3

    ... L Sinking/sourcing 30% overshoot ±1. −V = −5 V − −V = − −6 V − Rev Page AD8045 . S Typ Max Unit 1000 MHz 350 400 MHz 55 MHz 1350 V/µs 7.5 ns −102/−101 dBc −106/−101 dBc − ...

  • Page 4

    ... AD8045 SPECIFICATIONS WITH +5 V SUPPLY T = 25° + 100 Ω kΩ to midsupply, unless otherwise noted. Exposed paddle must be floating or connected to − Table 2. Parameter DYNAMIC PERFORMANCE –3 dB Bandwidth Bandwidth for 0.1 dB Flatness Slew Rate Settling Time to 0.1% NOISE/HARMONIC PERFORMANCE Harmonic Distortion (dBc) HD2/HD3 ...

  • Page 5

    ... Therefore, proper ESD precautions are recommended to avoid performance degradation and loss of functionality. The power dissipated in the package (P escent power dissipation and the power dissipated in the die due to the AD8045 drive at the output. The quiescent power is the voltage between the supply pins (V − 0 0.7 V ...

  • Page 6

    ... AD8045 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS AD8045 OUTPUT 6 3 BOTTOM VIEW (Not to Scale CONNECT Figure 5. SOIC Pin Configuration Note: The exposed paddle must be connected to −V Table 5. 8-Lead SOIC Pin Function Descriptions Pin No. Mnemonic Description 1 FEEDBACK Feedback Pin 2 − ...

  • Page 7

    ... ± 1kΩ –1 –2 +125°C –3 –4 –5 +25°C –6 10 100 FREQUENCY (MHz) 6 ± 499Ω 150Ω p-p OUT 6 200mV p-p OUT 5.9 5.8 5 100 FREQUENCY (MHz) AD8045 1000 –40°C 1000 ...

  • Page 8

    ... AD8045 –1 –2 –3 – ±2.5V S –5 –6 –7 –8 –9 –10 10 100 FREQUENCY (MHz) Figure 13. Large Signal Frequency Response for Various Supplies –1 –2 –3 – 100Ω L –5 –6 –7 –8 –9 –10 10 100 FREQUENCY (MHz) Figure 14. Large Signal Frequency Response for Various Loads ...

  • Page 9

    ... Figure 24. Harmonic Distortion vs. Output Voltage for Various Packages Rev Page AD8045 HD2 SOIC HD2 LFCSP HD3 SOIC AND LFCSP 1 10 100 FREQUENCY (MHz) HD2 SOIC HD2 LFCSP HD3 SOIC AND LFCSP 1 ...

  • Page 10

    ... AD8045 – ± 150Ω – 100Ω 10MHz –60 HD2 LFCSP –70 HD2 SOIC –80 –90 –100 HD3 SOIC AND LFCSP –110 OUTPUT AMPLITUDE (V p-p) Figure 25. Harmonic Distortion vs. Output Voltage for Various Packages – – ...

  • Page 11

    ... 10pF 30Ω SNUB V = ± SNUB 30Ω 10pF 1kΩ TIME (ns TIME (ns) Figure 36. Small Signal Transient Response for Various Loads AD8045 ±2. 1kΩ 150kΩ ...

  • Page 12

    ... AD8045 0.20 18pF 0.15 0.10 0pF 0.05 0 –0.05 –0. –0. ± 1kΩ L –0. TIME (ns) Figure 37. Small Signal Transient Response with Capacitive Load ± 100Ω LOAD = 1kΩ OR 150Ω –1 –2 – TIME (ns) Figure 38 ...

  • Page 13

    ... 10k 1000 100 10 1 10M 100M Rev Page ±5V –PSR +PSR 0 100 FREQUENCY (MHz) Figure 46. Power Supply Rejection vs. Frequency = ±5V = 499Ω 100 FREQUENCY (MHz) = ±5V 10 100 FREQUENCY (MHz) Figure 48. Input Impedance vs. Frequency AD8045 1000 1000 1000 ...

  • Page 14

    ... AD8045 1000 ±5V S 100 10 1 0.1 0. FREQUENCY (MHz) Figure 49. Output Impedance vs. Frequency FREQUENCY (MHz) Figure 50. Third-Order Intercept vs. Frequency 0 –0.02 GAIN –0. ±5V S –0.06 –0.08 –0.10 –0.12 –0.14 –0.16 PHASE –0.18 –0.20 1 NUMBER OF 150Ω LOADS Figure 51. Differential Gain and Phase vs. Number of 150 Ω ...

  • Page 15

    ... R = 150Ω L –3 –4 –4 –3 –2 – (V) OUT 2.5 5.0 7.5 10.0 12.5 15.0 17.5 TIME (ns) Figure 60. Short Term 0.1% Settling Time AD8045 +V – OUT –V – OUT 1kΩ ± p-p OUT = 150Ω 499Ω F 20.0 22.5 ...

  • Page 16

    ... S + 0.1µ AD8045 0.1µF 10µF + –V S Figure 61. Noninverting Configuration , is used SNUB improves SNUB R SNUB V OUT Rev Page 10µ 0.1µ SNUB AD8045 V OUT 0.1µ || 10µF + –V S Figure 62. Inverting Configuration ...

  • Page 17

    ... THEORY OF OPERATION The AD8045 is a high speed voltage feedback amplifier fabri- cated on ADI’s second generation eXtra Fast Complementary Bipolar (XFCB) process. An H-bridge input stage is used to attain a 1400 V/µs slew rate and low distortion in addition to a low 3 nV/√Hz input voltage noise. Supply current and offset voltage are laser trimmed for optimum performance ...

  • Page 18

    ... AD8045 OUTPUT NOISE Figure 66 shows the contributors to the noise at the output of a noninverting configuration – Figure 66. Amplifier DC Errors Ven , IN+ , and IN− are due to the amplifier. V are due to the feedback network resistors source resistor, R rms sum of all the contributions ...

  • Page 19

    ... Pin 1 of the AD8045 or remove the potential on the Pin 1 solder pad. The designer does not need to use the dedicated feedback pin to provide feedback for the AD8045. The output pin of the AD8045 can still be used to pro- vide feedback to the inverting input of the AD8045. HIGH SPEED ADC DRIVER When used as an ADC driver, the AD8045 offers results compa- rable to transformers in distortion performance ...

  • Page 20

    ... IF strips. With a 400 MHz gain bandwidth product and high slew rate, the AD8045 is an ideal candidate for active filters. Figure 70 shows the frequency response of the 90 MHz LPF. In addition to the bandwidth requirements, the slew rate must be capable of supporting the full power bandwidth of the filter ...

  • Page 21

    ... 249Ω 10µ 249Ω 7.1pF 0.1µF –5V –5V R3 499Ω R7 499Ω Figure 73. 4-Pole, 90 MHz, Sallen-Key Low-Pass Filter Rev Page AD8045 M4.00ns A CH1 0.00V C3 7.1pF 10µF 0.1µ 49.9Ω OUTPUT 10µF R9 24.9Ω 0.1µF C5 5pF R8 499Ω ...

  • Page 22

    ... When laying out the AD8045 as a unity gain amplifier rec- ommended that a short, but wide, trace between the dedicated feedback pin and the inverting input to the amplifier be used to minimize stray parasitic inductance ...

  • Page 23

    ... If this pole occurs too close to the unity gain crossover point, the phase margin degrades. This is due to the additional phase loss associated with the pole. The AD8045 output can drive load capacitance directly gain of +2 with 30% overshoot, as shown in Figure 37. Larger capacitance values can be driven but must use a snub- ...

  • Page 24

    ... AD8045ARD-REEL7 1,000 AD8045ARDZ AD8045ARDZ-REEL 2,500 1 AD8045ARDZ-REEL7 1,000 AD8045ACP-R2 250 AD8045ACP-REEL 5,000 AD8045ACP-REEL7 1,500 1 AD8045ACPZ-R2 250 1 AD8045ACPZ-REEL 5,000 1 AD8045ACPZ-REEL7 1,500 Pb-free part. © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. ...