LMC6681 National Semiconductor, LMC6681 Datasheet
LMC6681
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LMC6681 Summary of contents
Page 1
... CMOS rail-to-rail amplifiers. The LMC6681/2 excellent choice for circuits where the common-mode volt- age range is a concern. The LMC6681/2/4 has a powerdown mode which can be controlled externally. In this powerdown mode, the supply current decreases from 700 µA per amplifier to less than 1 µ ...
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... Molded DIP 14-Pin Small Outline 16-Pin Molded DIP 16-Pin Small Outline www.national.com Temperature Range Industrial, −40˚C to +85˚C Drawing LMC6681AIN, LMC6681BIN LMC6681AIM, LMC6681BIM LMC6681AIMX, LMC6681B1MX LMC6682AIN, LMC6682BIN LMC6682AIM, LMC6682BIM LMC6682AIMX, LMC6682BIMX LMC6684AIN, LMC6684BIN LMC6684AIM, LMC6684BIM LMC6684AIMX, LMC6684BIMX 2 NSC Transport ...
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... Output Swing Operating Ratings (Note 1) Supply Voltage Junction Temperature Range LMC6681AI, LMC6681BI 2 kV LMC6682AI, LMC6682BI ± Supply Voltage LMC6684AI, LMC6684BI Thermal Resistance ( 12V N Package, 8-pin Molded DIP ± Package, 8-pin Surface Mount ± Package, 14-pin Molded DIP ...
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... Unless otherwise specified, all limits guaranteed for Boldface limits apply at the temperature extremes (Note 16). Symbol Parameter Output Short Sourcing Circuit Current Sinking Supply Current Single, LMC6681 S ON when Powered Dual, LMC6682 V CM Quad, LMC6684 Supply Current ...
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... V V Input Common Mode V CM CMRR Voltage Range V CMRR V Output Swing Supply Current Single, LMC6681 S ON when Powered ON V Dual, LMC6682 V Quad, LMC6684 V I Supply Current Single, LMC6681 S OFF when Powered OFF V Dual, LMC6682 V Quad, LMC6684 V = 25˚ 1.8V and 2.2V, V− = 0V, V ...
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... > CMRR 50 dB 5.3 −0 4.9 L 0.05 Single, LMC6681 0 Dual, LMC6682 1 Quad, LMC6684 3 Single, LMC6681 0 Dual, LMC6682 0 Quad, LMC6684 1 > 0.9V and R / LMC6681BI LMC6682BI LMC6684BI Units Limit Limit (Note 6) ...
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... L A Large Signal Voltage Gain (Note 12) I Output Short Circuit Sourcing Current (Note 14) Sinking, V (Note 14) I Supply Current Single, LMC6681 S ON when Powered Dual, LMC6682 V CM Quad, LMC6684 Supply Current Single, LMC6681 S OFF when Powered OFF V PD ...
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... Characteristics for I S OFF www.national.com Conditions Min + = 2.2V V − − − 10V V − 2.2V V − 1. specs) V − 2. − 4. 10V V − 9.45 8 LMC6681AI, LMC6681BI LMC6682AI, LMC6682BI Units LMC6684AI, LMC6684BI Typ Max 0.4 V 0.25 0.6 V 0.45 0.9 V 0.75 1.2 V 1.05 1.5 V 2.3 V 4.3 V 9.3 V ...
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... The maximum allowable power dissipation at any ambient temperature (max 2.5V. O < < − 0. 5V. For Sinking tests 9V > 0.6V and R / LMC6681AI LMC6681BI LMC6682AI LMC6682BI LMC6684AI LMC6684BI Units Limit Limit (Note 6) (Note 6) 200 200 µ µs 0.7 0.7 0.55 0.55 V/µs min 0.7 0.7 0.55 0.55 MHz Deg ...
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Typical Performance Characteristics Supply Current per Amplifier vs Supply Voltage DS012042-40 Input Voltage Noise vs Common-Mode Voltage DS012042-43 Frequency Response vs Temperature DS012042-46 www.national.com + = 3V, Single Supply Sourcing Current vs Output Voltage DS012042- ...
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Typical Performance Characteristics specified (Continued) CMRR vs Frequency DS012042-49 Crosstalk Rejection vs Frequency DS012042-52 Inverting Large Signal Pulse Response DS012042- 3V, Single Supply Positive PSRR vs Frequency DS012042-50 Slew Rate vs Supply Voltage DS012042-53 Non-Inverting ...
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Typical Performance Characteristics specified (Continued) Stability vs Capacitive Load DS012042-58 t Delay till Active-On ON after OFF = 3V Powerdown Mode DS012042-39 www.national.com + = 3V, Single Supply Stability vs Capacitive Load ...
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... FIGURE 4. The Input Common-Mode Voltage Range Extends to Both Supplies at V The amplifier is operational at V put common-mode voltage range, output swing, and CMRR specs. Figure 5 shows the response of the LMC6681/2/4 at DS012042-6 = 1.8V FIGURE 5 ...
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... No Output Phase Inversion V S 4.0 Capacitive Load Tolerance The LMC6681/2/4 can typically drive a 100 pF load with V = 10V at unity gain without oscillating. The unity gain fol- lower is the most sensitive configuration to capacitive load. Direct capacitive loading reduces the phase margin of op-amps. The combination of the op-amp’s output imped- ance and the capacitive load induces phase lag ...
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... It is generally recognized that any circuit which must operate with less than 1000 pA of leakage current requires special layout of the PC board. When one wishes to take advantage of the ultra-low input current of the LMC6681/2/4, typically less than 80 fA essential to have an excellent layout. Fortunately, the techniques of obtaining low leakages are quite simple ...
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... For the LMC6681/2/4, the input, output, and power pins are the same as those used in the standard configuration. One of the other pins, pin 5 in the case of the LMC6681, is used to enable the powerdown mode. The connection diagrams for the LMC6681/2/4 are on the front page of the datasheet. ...
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... Note that the V frequency for the surements is 5 Hz. The LMC6681/2/4 is ideal for DC type ap- plications where the powerdown pin is controlled by low fre- quency signals. When the LMC6681/2/4 is powered off, internal bias currents are shutoff. There is a inherent latency in the circuit, and the device has to power off for a certain period of time for the t spec to apply ...
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... Transducer Interface Circuits A. PIEZOELECTRIC TRANSDUCERS FIGURE 18. Transducer Interface Application The LMC6681 can be used for processing of transducer sig- nals as shown in the circuit below. The two 11 M provide a path for the DC currents to ground. Since the resis- tors are bootstrapped to the output, the AC input resistance of the LMC6681 is much higher ...
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... FIGURE 23. Comparator with Hysteresis Figure 23 shows the application of the LMC6681/2 comparator. The hysteresis is determined by the ratio of the two resistors. Since the supply current of the LMC6681/2/4 is less than 1 mA, it can be used as a low power comparator, in applications where the quiescent current is an important pa- = 3V, typical propagation delays would be on rameter ...
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... This implies a reduction in cost, and savings of space and power. This is an illustration of the conceptual use of the LMC6681/ 2/4. The selectivity of the filter can be improved by increas- ing the order (number of poles) of the design. ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number LMC6681AIM or LMC6681BIM Order Number LMC6682AIM or LMC6682BIM 8-Pin Small Outline Package NS Package Number M08A 14-Pin Small Outline Package NS Package Number M14A 21 www.national.com ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) www.national.com 16-Pin Small Outline Package Order Number LMC6684AIM or LMC6684BIM NS Package Number M16A 8-Pin Molded Dual-In-Line Package Order Number LMC6681AIN or LMC6681BIN NS Package Number N08E 22 ...
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LMC6682AIN or LMC6682BIN Order Number LMC6684AIN or LMC6684BIN 14-Pin Molded Dual-In-Line Package NS Package Number N14A 16-Pin Molded Dual-In-Line Package NS Package Number N16A 23 www.national.com ...
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... National Semiconductor Asia Pacific Customer Fax: +49 (0) 1 80-530 85 86 Response Group Email: europe.support@nsc.com Tel: 65-2544466 Fax: 65-2504466 Tel: +49 (0) 1 80-532 78 32 Email: sea.support@nsc.com Tel: +49 (0) 1 80-534 16 80 National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 ...