MAX4207 Maxim, MAX4207 Datasheet
MAX4207
Related parts for MAX4207
MAX4207 Summary of contents
Page 1
... The device operates from dual ±2.7V to ±5.5V supplies and is capable of measuring five decades of input current across a 10nA to 1mA range. The MAX4207’s uncommitted op amp can be used for a variety of functions, including filtering noise, adding offset, and adding additional gain. A 0.5V reference is ...
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... CMVIN............................................................(V Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS— ...
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Precision Transimpedance Logarithmic Amplifier with Over 5 Decades of Dynamic Range DC ELECTRICAL CHARACTERISTICS—Dual-Supply Operation (continued +5V -5V, GND = REF T = -40°C to +85°C. Typical values are ...
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Precision Transimpedance Logarithmic Amplifier with Over 5 Decades of Dynamic Range (V = +5V -5V, GND = 0V REF T = +25°C, unless otherwise noted vs. I LOGV1 LOG 0.75 0.50 0.25 0 ...
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... I (A) LOG I PULSE RESPONSE REF (I = 1µA) LOG MAX4207 toc14 0.75V 0.50V 0.50V 0.25V 0.25V 0V 0V -0.25V 20µs/div > 1MΩ, SET vs LOG 100µ 1m 10m 100µA TO 1mA 10µA TO 100µA 1µ ...
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Precision Transimpedance Logarithmic Amplifier with Over 5 Decades of Dynamic Range (V = +5V -5V, GND = 0V REF T = +25°C, unless otherwise noted VOLTAGE-NOISE DENSITY LOGV2 vs. FREQUENCY 10 10nA 100nA ...
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... I LOG C = 33pF COMP - 330Ω 0V COMP I = 10µA REF -60 100 1k 10k 100k FREQUENCY (Hz) SMALL-SIGNAL AC RESPONSE OF BUFFER -12 10k 100k 1M 10M 100M FREQUENCY (Hz) > 1MΩ, SET MAX4207 toc25 0V 1.238V ) = 100µA = 10µA = 1µA = 100nA 1M 10M 7 ...
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... REFISET to GND, adjusts the current at SET is the common-mode voltage for the input and reference CMVIN REFVOUT CMVOUT V CC CURRENT MIRROR 1.238V CURRENT V CC CORRECTION 0.5V SUMMING AMPLIFIER AND TEMPERATURE COMPENSATION MAX4207 Pin Description is the reference REFIIN REFIOUT REFISET LOGV2 V CC SCALE OSADJ V EE LOGV1 ...
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... MAX4207’s output from the best-fit straight line of the to the refer- BE1 V LOGV1 a percent of the full-scale output or an output voltage. Referred-to-Input and Referred-to-Output Errors The log nature of the MAX4207 insures that any addi- tive error at LOGV1 corresponds to multiplicative error at the input, regardless of input level − ...
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... OSOUT put offset voltages, respectively. Output offset is defined as the offset occurring at the output of the MAX4207 when equal currents are presented to I Because the MAX4207 is configured with a gain -0.25V/decade should multiply the (±V term and V were derived from this default ...
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... I (see Figure 5) adjusts the reference current, according to the following equation: where V 5MΩ. REFIOUT current range is 10nA to 10µA only. The MAX4207 operates only from dual ±2.7 to ±5.5V sup- plies. The relationship of inputs to outputs is a function relative to I REF mitted amplifier ...
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... OSADJ REFOUT R The scale factor the slope of the logarithmic output. For the LOGV1 amplifier -0.25V/decade. Adjust the overall scale factor for the MAX4207 using the uncom- mitted LOGV2 amplifier and the following equation, which refers to Figure ...
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... GND 330Ω TO LIMITING TIA AMPLIFIER The MAX4207 drives capacitive loads 50pF. Reactive loads decrease phase margin and can pro- duce excessive ringing and oscillation. Use an isolation CMVIN resistor in series with LOGV1 or LOGV2 to reduce the effect of large capacitive loads. Recall that the combi- nation of the capacitive load and the small isolation resistor limits AC performance ...
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Precision Transimpedance Logarithmic Amplifier with Over 5 Decades of Dynamic Range Layout and Bypassing Bypass V and V to GND with ceramic 0.1µ capacitors. Place the capacitors as close to the device as possible. Bypass REFVOUT and/or CMVOUT ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © ...