Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Op-amp Voltage feedback SOT 23 5

402W

14-Bit

10MSPS

24.9W

2kW2kW

2kW

0.1 Fm

(+2V)

REFB

(+1V)

VREF

SEL

REFT

(+3V)

100pF

+5V

-5V

50W

+5V

OPA842

ADS850

OPA842

www.ti.com

SBOS267D –NOVEMBER 2002–REVISED SEPTEMBER 2010

Wideband, Low Distortion, Unity-Gain Stable, Voltage-Feedback

OPERATIONAL AMPLIFIER

Check for Samples: OPA842

FEATURES

DESCRIPTION

• UNITY-GAIN BANDWIDTH: 400MHz

The OPA842 provides a level of speed and dynamic

range previously unattainable in a monolithic op amp.

• GAIN-BANDWIDTH PRODUCT: 200MHz

Using unity-gain stable, voltage-feedback architecture

• LOW INPUT VOLTAGE NOISE: 2.6nV/√Hz

with two internal gain stages, the OPA842 achieves

• VERY LOW DISTORTION: –93dBc (5MHz)

exceptionally low harmonic distortion over a wide

• HIGH OPEN-LOOP GAIN: 110dB frequency range. The classic differential input

provides all the familiar benefits of precision op amps,

• FAST 12-BIT SETTLING: 22ns (0.01%)

such as bias current cancellation and very low

• LOW DC VOLTAGE OFFSET: 300mV Typical

inverting current noise compared with wideband

• PROFESSIONAL LEVEL DIFF GAIN/PHASE

current differential gain/phase performance,

low-voltage noise, and high output current drive make

ERROR: 0.003%/0.008°

the OPA842 ideal for most high dynamic range

applications.

APPLICATIONS

• ADC/DAC BUFFER DRIVER

Unity-gain stability makes the OPA842 particularly

suitable for low-gain differential amplifiers,

• LOW DISTORTION IF AMPLIFIER

transimpedance amplifiers, gain of +2 video line

• ACTIVE FILTER CONFIGURATION

drivers, wideband integrators, and low-distortion

• LOW-NOISE DIFFERENTIAL RECEIVER

analog-to-digital converter (ADC) buffers. Where

• HIGH-RESOLUTION IMAGING

higher gain or even lower harmonic distortion is

• TEST INSTRUMENTATION

required, consider the OPA843—a higher-gain

bandwidth and lower-noise version of the OPA842.

• PROFESSIONAL AUDIO

• OPA642 UPGRADE

OPA842 RELATED PRODUCTS

INPUT NOISE GAIN-BANDWIDTH

SINGLES VOLTAGE (nV/√Hz) PRODUCT (MHz)

OPA843 2.0 800

OPA846 1.1 2500

OPA847 0.8 3700

AC-Coupled to 14-Bit ADS850 Interface

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.

2All 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 the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (29 pages)

PAGE 1
OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 Wideband, Low Distortion, Unity-Gain Stable, Voltage-Feedback OPERATIONAL AMPLIFIER Check for Samples: OPA842 FEATURES DESCRIPTION • • • • • • • • The OPA842 provides a level of speed and dynamic range previously unattainable in a monolithic op amp. Using unity-gain stable, voltage-feedback architecture with two internal gain stages, the OPA842 achieves exceptionally low harmonic distortion over a wide frequency range.
PAGE 2
OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure.
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OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 ELECTRICAL CHARACTERISTICS: VS = ±5V Boldface limits are tested at +25°C. At TA = +25°C, VS = ±5V, RF = 402Ω, RL = 100Ω, and G = +2, unless otherwise noted. See Figure 37 for ac performance.
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OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com ELECTRICAL CHARACTERISTICS: VS = ±5V (continued) Boldface limits are tested at +25°C. At TA = +25°C, VS = ±5V, RF = 402Ω, RL = 100Ω, and G = +2, unless otherwise noted. See Figure 37 for ac performance.
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OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 TYPICAL CHARACTERISTICS: VS = ±5V At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω, unless otherwise noted. NONINVERTING SMALL−SIGNAL FREQUENCY RESPONSE 3 G = +1 RF = 25W 0 Normalized Gain (3dB/div) Normalized Gain (3dB/div) 3 INVERTING SMALL−SIGNAL FREQUENCY RESPONSE G = +2 -3 VO = 0.
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OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V (continued) At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω, unless otherwise noted.
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OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 TYPICAL CHARACTERISTICS: VS = ±5V (continued) At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω, unless otherwise noted. TWO−TONE, THIRD−ORDER INTERMODULATION INTERCEPT INPUT VOLTAGE AND CURRENT NOISE 100 50 PI 50W Intercept Point (+dBm) Voltage Noise (nV/ÖHz) Current Noise (pA/ÖHz) 45 10 Current Noise 2.
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OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V (continued) At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω, unless otherwise noted.
PAGE 9
OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 TYPICAL CHARACTERISTICS: VS = ±5V (continued) At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω, unless otherwise noted. SETTLING TIME VIDEO DIFFERENTIAL GAIN/DIFFERENTIAL PHASE 0.250 G=2 Differential Gain (%) 0.150 0.100 0.050 0 -0.050 -0.100 0.006 0.06 DG Negative Video DP Negative Video 0.04 0.004 DP Positive Video 0.02 0.002 Differential Phase (°) VO = 2V Step RL = 100W G=2 0.200 Percent of Final Value (%) 0.08 0.
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OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com TYPICAL CHARACTERISTICS: VS = ±5V (continued) At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω, unless otherwise noted. DIFFERENTIAL SMALL-SIGNAL FREQUENCY RESPONSE DIFFERENTIAL PERFORMANCE TEST CIRCUIT 3 +5V GD = 1 OPA842 GD = Normalized Gain (dB) 0 402W RG -5V VI RG 402W RG 402W RL VO GD = 2 -3 GD = 5 -6 GD = 10 -9 -12 -15 +5V -18 1 10 100 500 Frequency (MHz) OPA842 -5V Figure 31. Figure 32.
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OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 APPLICATION INFORMATION WIDEBAND CURRENT FEEDBACK OPERATION WIDEBAND INVERTING OPERATION The OPA842 combination of speed and dynamic range is easily achieved in a wide variety of application circuits, providing that simple principles of good design practice are observed. For example, good power-supply decoupling, as shown in Figure 37, is essential to achieve the lowest possible harmonic distortion and smooth frequency response.
PAGE 12
OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 with RG and RM. Although this resistor will provide cancellation for the bias current, it must be well-decoupled (0.1mF in Figure 38) to filter the noise contribution of the resistor and the input current noise. As the required RG resistor approaches 50Ω at higher gains, the bandwidth for the circuit in Figure 38 will far exceed the bandwidth at that same gain magnitude for the noninverting circuit of Figure 37.
PAGE 13
OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 SINGLE OP AMP DIFFERENTIAL AMPLIFIER The voltage-feedback architecture of the OPA842, with its high Common-Mode Rejection Ratio (CMRR), will provide exceptional performance in differential amplifier configurations. Figure 39 shows a typical configuration. The starting point for this design is the selection of the RF value in the range of 200Ω to 2kΩ.
PAGE 14
OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com DAC TRANSIMPEDANCE AMPLIFIER High-frequency digital-to-analog converters (DACs) require a low-distortion output amplifier to retain the SFDR performance into real-world loads. A single-ended output drive implementation is shown in Figure 41. In this circuit, only one side of the complementary output drive signal is used.
PAGE 15
OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 MACROMODELS AND APPLICATIONS SUPPORT DESIGN-IN TOOLS DEMONSTRATION FIXTURES Two printed circuit boards (PCBs) are available to assist in the initial evaluation of circuit performance using the OPA842 in its two package options. Both of these are offered free of charge as unpopulated PCBs, delivered with a user's guide. The summary information for these fixtures is shown in Table 1. Table 1.
PAGE 16
OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 than the value predicted by dividing GBP by the noise gain. Increasing the gain will cause the phase margin to approach 90 degrees and the bandwidth to more closely approach the predicted value of (GBP/NG). At a gain of +10, the 21MHz bandwidth shown in the Electrical Characteristics agrees with that predicted using the simple formula and the typical GBP of 200MHz.
PAGE 17
OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 approximately 600Hz. Starting from the –100dBc second-harmonic for 2VPP into 200Ω, G = +2 distortion at 1MHz (from the Typical Characteristics), the second-harmonic distortion at 20kHz should be approximately: ENI EO OPA842 RS IBN –100dB – 20log (1MHz/20kHz) = –134dBc The OPA842 has an extremely low third-order harmonic distortion.
PAGE 18
OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 DC OFFSET CONTROL The OPA842 can provide excellent dc signal accuracy due to its high open-loop gain, high common-mode rejection, high power-supply rejection, and low input offset voltage and bias current offset errors. To take full advantage of this low input offset voltage, careful attention to input bias current cancellation is also required.
PAGE 19
OPA842 www.ti.com SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 can create significant time constants that can degrade performance. Good axial metal-film or surface-mount resistors have approximately 0.2pF in shunt with the resistor. For resistor values greater than 1.5kΩ, this parasitic capacitance can add a pole and/or a zero below 500MHz that can affect circuit operation. Keep resistor values as low as possible consistent with load-driving considerations.
PAGE 20
OPA842 SBOS267D – NOVEMBER 2002 – REVISED SEPTEMBER 2010 www.ti.com REVISION HISTORY NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision C (December, 2008) to Revision D Page • Updated document format to current standards ................................................................................................................... 1 • Deleted lead temperature specifications from Absolute Maximum Ratings table ......................
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.com 11-Apr-2013 (4) Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Top-Side Marking for that device. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided.
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PACKAGE MATERIALS INFORMATION www.ti.com 14-Jul-2012 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) OPA842IDBVR SOT-23 DBV 5 3000 180.0 OPA842IDBVT SOT-23 DBV 5 250 OPA842IDR SOIC D 8 2500 B0 (mm) K0 (mm) P1 (mm) 8.4 3.2 3.1 1.39 4.0 180.0 8.4 3.2 3.1 1.39 330.0 12.4 6.4 5.2 2.1 Pack Materials-Page 1 W Pin1 (mm) Quadrant 8.0 Q3 4.0 8.0 Q3 8.0 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 14-Jul-2012 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) OPA842IDBVR SOT-23 DBV 5 3000 210.0 185.0 35.0 OPA842IDBVT SOT-23 DBV 5 250 210.0 185.0 35.0 OPA842IDR SOIC D 8 2500 367.0 367.0 35.
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IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.