AD8137 Analog Devices, AD8137 Datasheet
AD8137
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AD8137 Summary of contents
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... The AD8137 is a low cost differential driver with a rail-to-rail output that is ideal for driving 12-bit ADCs in systems that are sensitive to power and cost. The AD8137 is easy to apply, and its internal common-mode feedback architecture allows its output common-mode voltage to be controlled by the voltage applied to one pin ...
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... AD8137 TABLE OF CONTENTS Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 6 Thermal Resistance ...................................................................... 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 17 REVISION HISTORY 7/05—Rev Rev. B Changes to Ordering Guide .......................................................... 24 8/04—Rev Rev. A. Added 8-Lead LFCSP.........................................................Universal Changes to Layout ..............................................................Universal Changes to Product Title ................................................................. 1 Changes to Figure 1 ...
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... V p 0 100 kHz to 1 MHz ∆V /∆V , ∆V = ±0 OCM OCM Power-down = low ∆V = ± Power-Down = high/low Rev Page AD8137 −40°C to +125°C). MIN MAX Min Typ Max 110 450 100 8.25 1 − ...
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... AD8137 2 25°C, differential gain = OCM Table 2. Parameter DIFFERENTIAL INPUT PERFORMANCE DYNAMIC PERFORMANCE −3 dB Small Signal Bandwidth −3 dB Large Signal Bandwidth Slew Rate Settling Time to 0.02% Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE SFDR Input Voltage Noise Input Current Noise DC PERFORMANCE ...
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... V p 100 kHz to 5 MHz ∆V /∆V , ∆V = ±0 OCM OCM Power-down = low ∆V = ± Power-down = high/low Rev Page AD8137 −40°C to +125°C). MIN MAX Min Typ Max Unit 61 73 MHz 62 93 MHz 340 V/µs ...
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... LFCSP/4-Layer 70 Maximum Power Dissipation The maximum safe power dissipation in the AD8137 package is limited by the associated rise in junction temperature (T the die. At approximately 150°C, which is the glass transition temperature, the plastic changes its properties. Even tempo- rarily exceeding this temperature limit may change the stresses that the package exerts on the die, permanently shifting the parametric performance of the AD8137 ...
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... Figure 5. Basic Test Circuit R = 1kΩ F 50Ω 1kΩ G 52.3Ω + AD8137 V MIDSUPPLY OCM 52.3Ω – 50Ω 1kΩ 1kΩ F Figure 6. Capacitive Load Test Circuit Rev Page – R 1kΩ – AD8137 ...
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... AD8137 TYPICAL PERFORMANCE CHARACTERISTICS Unless otherwise noted, differential gain = 1, R Figure 5 for the definition of terms – –2 –3 –4 – –6 –7 –8 –9 – 1kΩ G – 0.1V p –12 0 FREQUENCY (MHz) Figure 7. Small Signal Frequency Response for Various Gains ...
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... Figure 18. Frequency Response for Various Output Amplitudes OCM Rev Page Ω Ω p 100 FREQUENCY (MHz 0pF 1pF 2pF 2.0V p 100 FREQUENCY (MHz) 0.5V p-p 2V p-p 1V p-p 0.1V p-p 10 100 FREQUENCY (MHz) AD8137 = 500 Ω 1000 1000 F 1000 ...
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... AD8137 – Ω R –2 F – Ω – –5 –6 –7 – –9 = ± – 0.1V p – FREQUENCY (MHz) Figure 19. Small Signal Frequency Response for Various R – p –70 – +3V S –80 –85 = ± 5V ...
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... Figure 30. Third Harmonic Distortion at Various R F Rev Page p 200 Ω Ω 500 Ω FREQUENCY (MHz p Ω FREQUENCY (MHz p 500 Ω Ω Ω FREQUENCY (MHz) AD8137 ...
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... AD8137 – 500kHz p SECOND HARMONIC SOLID LINE –60 THIRD HARMONIC DASHED LINE –70 –80 –90 –100 –110 0.5 1.0 1.5 2.0 2.5 V (V) OCM Figure 31. Harmonic Distortion vs. V 100 100 1k 10k 100k FREQUENCY (Hz) Figure 32. Input Voltage Noise vs. Frequency 0.2V p-p IN, cm INPUT CMRR = ∆ V ∆ ...
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... Figure 42. Large Signal Transient Response for Various Capacitive Loads Rev Page 2 0pF INPUT 1.0 0.5 0 ERROR = 110ns SETTLE TIME (ns) Figure 40. Settling Time (0.02%) 1 0pF F 2V p-p 1 1pF 0pF 1V p 1pF F 0 TIME (ns) Capacitances 1 111 5pF S L 1.0 0 60. 15pF TIME (ns) AD8137 = 3.5V p-p - INPUT 50ns/DIV 20ns/DIV 20ns/DIV ...
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... AD8137 –5 PSRR = ∆V ∆V O, dm/ S –15 –25 –35 –PSRR –45 +PSRR –55 –65 –75 –85 0 FREQUENCY (MHz) Figure 43. PSRR vs. Frequency 1 0 –1 –2 –3 –4 –5 –6 – –8 –9 –10 V –11 –12 – 0.1V p – FREQUENCY (MHz) Figure 44 ...
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... Rev Page – TEMPERATURE (°C) Figure 52. Supply Current vs. Temperature 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 V (V) OCM Figure 53. V Bias Current vs. V Input Voltage OCM OCM – 100 TEMPERATURE (°C) Figure 54. V Bias Current vs. Temperature OCM AD8137 100 120 4.5 5.0 120 ...
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... AD8137 –1 = ± –2 –3 –4 –5 –5 –4 –3 –2 – OCM Figure 55. V vs. V Input Voltage O, cm OCM –20 –40 –60 –80 –100 –120 0 0.5 1.0 1.5 2.0 2.5 3.0 PD VOLTAGE (V) Figure 56. PD Current vs. PD Voltage – ...
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... THEORY OF OPERATION The AD8137 is a low power, low cost, fully differential voltage feedback amplifier that features a rail-to-rail output stage, common-mode circuitry with an internally derived common- mode reference voltage, and bias shutdown circuitry. The amplifier uses two feedback loops to separately control differ- ential and common-mode feedback ...
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... AD8137 APPLICATIONS ANALYZING A TYPICAL APPLICATION WITH MATCHED R AND R NETWORKS F G Typical Connection and Definition of Terms Figure 63 shows a typical connection for the AD8137, using matched external R /R networks. The differential input F G terminals of the AD8137, V and V , are used as summing AP AN junctions. An external reference voltage applied to the V terminal sets the output common-mode voltage ...
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... The differential output voltage noise contains contributions from the AD8137’s input voltage noise and input current noise as well as those from the external feedback networks. The contribution from the input voltage noise spectral density is computed as ⎛ ⎞ ⎜ + ⎟ F Vo_n ...
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... V p-p swinging IN has an ICM Another way to avoid the input common-mode swing limita- tion is to use dual power supplies on the AD8137. In this case, the biasing circuitry is not required. in this case is ACM Bandwidth vs. Closed-Loop Gain The AD8137’ bandwidth will decrease proportionally to ...
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... Estimating DC Errors Primary differential output offset errors in the AD8137 are due to three major components: the input offset voltage, the offset between the V and V input currents interacting with the AN AP feedback network resistances, and the offset produced by the dc voltage difference between the input and output common-mode voltages in conjunction with matching errors in the feedback network ...
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... Power Down –5V The AD8137 features a PD pin that can be used to minimize the quiescent current consumed when the device is not being used asserted by applying a low logic level to Pin 7. The thresh- old between high and low logic levels is nominally 1.1 V above the negative supply rail ...
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... Figure 69. AD8137 Performance −1 V Supplies, −0.45 dBFS Rev Page 33Ω 1nF AD7687 GND 33Ω 1nF THD = –91.75dBc SNR = 91.35dB SINAD = 88.75dB ENOB = 14.4 ...
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... AD8137YRZ-REEL −40°C to +125°C AD8137YRZ-REEL7 1 −40°C to +125°C AD8137YCP-R2 –40°C to +125°C AD8137YCP-REEL –40°C to +125°C AD8137YCP-REEL7 –40°C to +125°C 1 AD8137YCPZ-R2 –40°C to +125°C 1 AD8137YCPZ-REEL –40°C to +125°C 1 AD8137YCPZ-REEL7 –40°C to +125° Pb-free part ...