MAX44244/MAX44245/MAX V, Precision, Low-Power, 90µA, Single/Quad/Dual Op Amps

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1 EVALUATION KIT AVAILABLE MAX4444/MAX444/MAX V, Precision, Low-Power, 9µA, General Description The MAX4444/MAX444/MAX4448 family of parts provide ultra-precision, low-noise, zero-drift single/quad/ dual operational amplifiers featuring very low-power operation with a wide supply range. The devices incorporate a patented auto-zero circuit that constantly measures and compensates the input offset to eliminate drift over time and temperature as well as the effect of /f noise. These devices also feature integrated EMI filters to reduce high-frequency signal demodulation on the output. The op amps operate from either a single.7v to 36V supply or dual ±.3V to ±8V supply. The devices are unity-gain stable with a MHz gain-bandwidth product and a low 9µA supply current per amplifier. The low offset and noise specifications and high supply range make the devices ideal for sensor interfaces and transmitters. The devices are available in FMAXM, SO, SOT3, and TSSOP packages and are specified over the -4NC to +NC automotive operating temperature range. Sensors Interfaces 4mA to ma and tov Transmitters PLC Analog I/O Modules Weight Scales Portable Medical Devices Applications Benefits and Features Reduces Power for Sensitive Precision Applications Low 9µA Quiescent Current per Amplifier Eliminates the Cost of Calibration with Increased Accuracy with Maxim s Patented Autozero Circuitry Very Low Input Voltage Offset 7.µV (max) Low 3nV/NC Offset Drift (max) Low Noise Ideal for Sensor Interfaces and Transmitters nv/ Hz at khz.µv P-P from.hz to Hz MHz Gain-Bandwidth Product EMI Suppression Circuitry Rail-to-Rail Output Wide Supply for High-Voltage Front Ends.7V to 36V Supply Range µmax, SO, SOT3, TSSOP Packages Ordering Information appears at end of data sheet. µmax is a registered trademark of Products, Inc. Typical Operating Circuit LP+ MAX633 REF MAX6 DAC R V REF R MAX4444 I SIG (4-mA) R3 FLOATING GROUND R SENSE LP- For pricing, delivery, and ordering information, please contact Maxim Direct at , or visit Maxim s website at ; Rev ; 9/

2 ABSOLUTE MAXIMUM RATINGS V DD to V SS...-.3V to +4V Common-Mode Input Voltage...(V SS -.3V) to (V DD +.3V) Differential Input Voltage IN_+, IN_-...6V Continuous Input Current Into Any Pin... QmA Output Voltage to V SS (OUT_)....3V to (V DD +.3V) Output Short-Circuit Duration (OUT_)... s MAX4444/MAX444/MAX V, Precision, Low-Power, 9µA, 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. PACKAGE THERMAL CHARACTERISTICS (Note ) SO-8 Junction-to-Ambient Thermal Resistance (B JA )...3NC/W Junction-to-Case Thermal Resistance (B JC )...38NC/W SO-4 Junction-to-Ambient Thermal Resistance (B JA )...NC/W Junction-to-Case Thermal Resistance (B JC )...37NC/W SOT3 Junction-to-Ambient Thermal Resistance (B JA ) NC/W Junction-to-Case Thermal Resistance (B JC )...8NC/W Operating Temperature Range... -4NC to +NC Storage Temperature... -6NC to +NC Junction Temperature...+NC Lead Temperature (soldering, s)...+3nc Soldering Temperature (reflow)...+6nc TSSOP Junction-to-Ambient Thermal Resistance (B JA )...NC/W Junction-to-Case Thermal Resistance (B JC )...3NC/W FMAX Junction-to-Ambient Thermal Resistance (B JA )...6.3NC/W Junction-to-Case Thermal Resistance (B JC )...4NC/W Note : Package thermal resistances were obtained using the method described in JEDEC specification JESD-7, using a four-layer board. For detailed information on package thermal considerations, refer to ELECTRICAL CHARACTERISTICS (V DD = V, V SS = V, V IN+ = V IN- = V DD /, R L = ki to V DD /, T A = -4NC to +NC, unless otherwise noted. Typical values are at +NC.) (Note ) POWER SUPPLY PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage Range V DD Guaranteed by PSRR.7 36 V Power-Supply Rejection Ratio (Note 3) Quiescent Current Per Amplifier (MAX444 Only) Quiescent Current Per Amplifier (MAX444/MAX4448 Only) DC SPECIFICATIONS PSRR T A = +NC, V IN+ = V IN- = V DD / - V NC < T A < +NC 33 Input Common-Mode Range V CM Guaranteed by CMRR test T A = +NC 6 I DD -4NC < T A < +NC 9 T A = +NC 9 3 I DD -4NC < T A < +NC 4 V SS -. V DD -. db FA FA V

3 36V, Precision, Low-Power, 9µA, ELECTRICAL CHARACTERISTICS (continued) (V DD = V, V SS = V, V IN+ = V IN- = V DD /, R L = ki to V DD /, T A = -4NC to +NC, unless otherwise noted. Typical values are at +NC.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Common-Mode Rejection Ratio (Note 3) CMRR T A = +NC, V CM = V SS -.V to V DD -.V -4NC < T A < +NC, V CM = V SS -.V to V DD -.V 6 3 T A = +NC 7. Input Offset Voltage (Note 3) V OS -4NC < T A < +NC Input Offset Voltage Drift (Note 3) TC V OS 3 nv/nc T A = +NC 3 Input Bias Current (Note 3) I B -4NC < T A < +NC 7 T A = +NC 3 6 Input Offset Current (Note 3) I OS -4NC < T A < +NC 4 Open-Loop Gain (Note 3) AVOL V SS +.V P V OUT P V DD -.V T A = +NC 4-4NC < T A < +NC 3 Output Short-Circuit Current To V DD or V SS, noncontinuous 4 ma Output Voltage Swing AC SPECIFICATIONS V DD - T A = +NC 8 V OUT -4NC < T A < +NC V OUT - T A = +NC V SS -4NC < T A < +NC 7 Input Voltage-Noise Density e N f = khz nv/ Hz Input Voltage Noise.Hz < f < Hz nv P-P Input Current-Noise Density i N f = khz. pa/ Hz Gain-Bandwidth Product GBW MHz Slew Rate SR A V = V/V, V OUT = V P-P.7 V/Fs Capacitive Loading C L No sustained oscillation, A V = V/V 4 pf Total Harmonic Distortion Plus Noise EMI Rejection Ratio EMIRR V RF_PEAK = mv THD+N V OUT = V P-P, A V = +V/V, f = khz - db f = 4MHz 7 f = 9MHz 78 f = 8MHz 8 f = 4MHz 9 db FV pa pa db mv db 3

4 36V, Precision, Low-Power, 9µA, ELECTRICAL CHARACTERISTICS (V DD = 3V, V SS = V, V IN+ = V IN- = V DD /, R L = ki to V DD /, T A = -4NC to +NC, unless otherwise noted. Typical values are at +NC.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER SUPPLY Quiescent Current Per Amplifier (MAX4444 Only) Quiescent Current Per Amplifier (MAX444/MAX4448 Only) DC SPECIFICATIONS Input Common-Mode Range V CM Guaranteed by CMRR test Common-Mode Rejection Ratio (Note 3) T A = +NC 6 I DD -4NC < T A < +NC 9 T A = +NC 9 3 I DD -4NC < T A < +NC 4 CMRR T A = +NC, V CM = V SS -.V to V DD -.V -4NC < T A < +NC, V CM = V SS -.V to V DD -.V V SS T A = +NC 7. Input Offset Voltage (Note 3) V OS -4NC < T A < +NC Input Offset Voltage Drift (Note 3) 6 V DD -. TC V OS 3 nv/ C T A = +NC 3 Input Bias Current (Note 3) I B -4NC < T A < +NC 7 T A = +NC 3 6 Input Offset Current (Note 3) I OS -4NC < T A < +NC 4 Open-Loop Gain (Note 3) A VOL V SS +.V P V OUT P V DD -.V T A = +NC 46-4NC < T A < +NC 4 Output Short-Circuit Current To V DD or V SS, noncontinuous 4 ma Output Voltage Swing AC SPECIFICATIONS V DD - T A = +NC V OUT -4NC < T A < +NC 7 V OUT - T A = +NC 4 V SS -4NC < T A < +NC Input Voltage-Noise Density e N f = khz nv/ Hz Input Voltage Noise.Hz < f < Hz nv P-P Input Current-Noise Density i N f = khz. pa/ Hz Gain-Bandwidth Product GBW MHz FA FA V db FV pa pa db mv 4

5 36V, Precision, Low-Power, 9µA, ELECTRICAL CHARACTERISTICS (continued) (V DD = 3V, V SS = V, V IN+ = V IN- = V DD /, R L = ki to V DD /, T A = -4NC to +NC, unless otherwise noted. Typical values are at +NC.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Slew Rate SR A V = V/V, V OUT = V P-P.7 V/Fs Capacitive Loading C L No sustained oscillation, A V = V/V 4 pf Total Harmonic Distortion Plus Noise THD+N V OUT = V P-P, A V = +V/V, f = khz - db f = 4MHz 7 EMI Rejection Ratio EMIRR V RF_PEAK = mv f = 9MHz 78 f = 8MHz 8 db f = 4MHz 9 Note : All devices are % production tested at T A = +NC. Temperature limits are guaranteed by design. Note 3: Guaranteed by design. Note 4: At IN+ and IN-. Defined as log (V RF_PEAK /δv OS ). (T (V A DD = = + C, V, Vunless SS = V, otherwise V IN+ = Vnoted.) IN- = V DD /, R L = kω to V DD /. Typical values are at T A = + C.) Typical Operating Characteristics OCCURANCE (%) INPUT OFFSET VOLTAGE HISTOGRAM MAX4448 toc OCCURANCE (%) 3 3 INPUT OFFSET VOLTAGE DRIFT MAX4448 toc SUPPLY CURRENT (µa) SUPPLY CURRENT vs. SUPPLY VOLTAGE MAX4448 toc INPUT OFFSET VOLTAGE (µv) INPUT OFFSET VOLTAGE DRIFT (nv/ C) SUPPLY VOLTAGE (V)

6 36V, Precision, Low-Power, 9µA, Typical Operating Characteristics (continued) (V DD = V, V SS = V, V IN+ = V IN- = V DD /, R L = kω to V DD /. Typical values are at T A = + C.) SUPPLY CURRENT (µa) SUPPLY CURRENT vs. TEMPERATURE MAX4448 toc4 OFFSET VOLTAGE (µv) INPUT OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE MAX4448 toc OFFSET VOLTAGE (µv) INPUT OFFSET VOLTAGE VS. TEMPERATURE MAX4448 toc TEMPERATURE ( C) COMMON-MODE VOLTAGE (V) TEMPERATURE ( C) INPUT BIAS CURRENT (pa) INPUT BIAS CURRENT VS. COMMON-MODE VOLTAGE MAX4448 toc7 INPUT BIAS CURRENT (pa) INPUT BIAS CURRENT vs. TEMPERATURE MAX4448 toc COMMON-MODE VOLTAGE (V) TEMPERATURE ( C) - COMMON-MODE REJECTION RATIO vs. FREQUENCY MAX4448 toc9 - - COMMON-MODE REJECTION RATIO vs. TEMPERATURE MAX4448 toc -4 - CMRR (db) -6-8 CMRR (db) k k k M TEMPERATURE ( C) 6

7 36V, Precision, Low-Power, 9µA, Typical Operating Characteristics (continued) (V DD = V, V SS = V, V IN+ = V IN- = V DD /, R L = kω to V DD /. Typical values are at T A = + C.) PSRR (db) POWER-SUPPLY REJECTION RATIO vs. FREQUENCY MAX4448 toc VDD - VOUT (mv) OUTPUT VOLTAGE HIGH vs. TEMPERATURE MAX4448 toc VOUT - VSS (mv) OUTPUT VOLTAGE LOW vs. TEMPERATURE MAX4448 toc3-6 k k k M TEMPERATURE ( C) TEMPERATURE ( C) OUTPUT VOLTAGE HIGH vs. SOURCE CURRENT MAX4448 toc4 OUTPUT VOLTAGE LOW vs. SINK CURRENT MAX4448 toc VDD - VOUT (mv) VOUT - VSS (mv). SOURCE CURRENT (ma). SINK CURRENT (ma) INPUT VOLTAGE NOISE (nv/ Hz) INPUT VOLTAGE NOISE vs. FREQUENCY k k k MAX4448 toc6 4nV/div INPUT VOLTAGE.Hz TO Hz NOISE MAX4448 toc7 s/div 7

8 36V, Precision, Low-Power, 9µA, Typical Operating Characteristics (continued) (V DD = V, V SS = V, V IN+ = V IN- = V DD /, R L = kω to V DD /. Typical values are at T A = + C.) INPUT-CURRENT NOISE (pa/ Hz) INPUT CURRENT NOISE vs. FREQUENCY k k k MAX4448 toc8 SMALL-SIGNAL GAIN (db) SMALL-SIGNAL GAIN vs. FREQUENCY k k k M MAX4448 toc9 LARGE-SIGNAL GAIN (db) LARGE-SIGNAL GAIN vs. FREQUENCY k k k M MAX4448 toc SMALL-SIGNAL STEP RESPONSE MAX4448 toc LARGE-SIGNAL STEP RESPONSE MAX4448 toc V IN mv/div V IN V/div V OUT mv/div V OUT mv/div 4µs/div 4µs/div V DD V/div POWER-UP TIME MAX4448 toc3 - TOTAL HARMONIC DISTORTION vs. FREQUENCY MAX4448 toc4-4 R LOAD = ki V OUT V/div THD (db) R LOAD = 6I - R LOAD = ki µs/div -4 k k k 8

9 36V, Precision, Low-Power, 9µA, Typical Operating Characteristics (continued) (V DD = V, V SS = V, V IN+ = V IN- = V DD /, R L = kω to V DD /. Typical values are at T A = + C.) RESISTIVE LOAD (I) k k OUTPUT STABILITY vs. CAPACITIVE LOAD STABLE UNSTABLE MAX4448 toc ISOLATION RESISTANCE (I) k k OUTPUT STABILITY vs. ISOLATION RESISTANCE STABLE UNSTABLE MAX4448 toc6 CROSSTALK (db),, CAPACITIVE LOAD (pf) CROSSTALK vs. FREQUENCY k k k M MAX4448 toc7 OUTPUT IMPEDANCE (I) ,, CAPACITIVE LOAD (pf) OUTPUT IMPEDANCE vs. FREQUENCY k k k M MAX4448 toc8 EMIRR vs. FREQUENCY MAX4448 toc9 8 EMIRR (db) 6 4,, FREQUENCY (MHz) 9

10 36V, Precision, Low-Power, 9µA, Pin Configurations TOP VIEW OUTA V SS + MAX4444 V DD N.C. INA- INA+ 3 + MAX N.C. V DD OUTA INA+ 3 4 INA- V SS 4 µmax N.C. SOT3 OUTD IND- OUTA INA IND- OUTA INA OUTD IND+ V SS INC+ INC- OUTC INA+ V DD INB+ INB- OUTB MAX INA+ 3 IND+ MAX444 V DD 4 V SS INB+ INC+ INB- 6 9 INC- TSSOP OUTB 7 SO-4 8 OUTC 3 + MAX V DD OUTB INB- INB+ OUTA INA- INA+ V SS MAX OUTA INA- INA+ V DD OUTB INB- V SS 4 INB+ µmax SO-8

11 PIN MAX4444 MAX444 MAX4448 SOT3 µmax SO-4 TSSOP SO-8 µmax MAX4444/MAX444/MAX V, Precision, Low-Power, 9µA, NAME Pin Description FUNCTION 6 OUTA Channel A Output V SS Negative Supply Voltage INA+ Channel A Positive Input 4 INA- Channel A Negative Input V DD Positive Supply Voltage INB+ Channel B Positive Input INB- Channel B Negative Input OUTB Channel B Output 8 8 OUTC Channel C Output 9 9 INC- Channel C Negative Input INC+ Channel C Positive Input IND+ Channel D Positive Input 3 3 IND- Channel D Negative Input 4 4 OUTD Channel D Output,, 8 N.C. No Connection. Not internally connected. Detailed Description The MAX4444/MAX444/MAX4448 are high-precision amplifiers with less than FV (typ) input-referred offset and low input voltage-noise density at Hz. /f noise, in fact, is eliminated to improve the performance in low-frequency applications. These characteristics are achieved through an auto-zeroing technique that cancels the input offset voltage and /f noise of the amplifier. External Noise Suppression in EMI Form These devices have input EMI filters to prevent effects of radio frequency interference on the output. The EMI filters comprise passive devices that present significant higher impedance to higher frequency signals. See the EMIRR vs. Frequency graph in the Typical Operating Characteristics section for details. High Supply Voltage Range The devices feature 9µA current consumption per channel and a voltage supply range from either.7v to 36V single supply or ±.3V to ±8V split supply. Applications Information The devices feature ultra-high precision operational amplifiers with a high supply voltage range designed for load cell, medical instrumentation, and precision instrument applications. 4 ma Current-Loop Communication Industrial environments typically have a large amount of broadcast electromagnetic interference (EMI) from highvoltage transients and switching motors. This combined with long cables for sensor communication leads to high-voltage noise on communication lines. Current-Loop communication is resistant to this noise because the EMI induced current is low. This configuration also allows for low-power sensor applications to be powered from the communication lines. The Typical Operating Circuit shows how the device can be used to make a current loop driver. The circuit uses low-power components such as the MAX4444 op amp, the 6-bit MAX6 DAC, and the high-precision 6µA-only MAX633 reference. In this

12 36V, Precision, Low-Power, 9µA, circuit, both the DAC and the reference are referred to the local ground. The MAX4444 op-amp inputs are capable of swinging to the negative supply (which is the local ground in this case). R3 acts as a current mirror with R SENSE. Therefore, if R SENSE = Ω (i.e. ma will drop V) and if the current through R3 is μa when I OUT is ma (.% error) then R3 = kω. R is chosen along with the reference voltage to provide the 4mA offset. R = kω for ma full scale or R = 64kΩ for % overrange. R SENSE is ratiometric with R3, R independently sets the offset current and R independently sets the DAC scaling. Driving High-Performance ADCs The MAX4444/MAX444/MAX4448 s low input offset voltage and low noise make these amplifiers ideal for ADC buffering. Weight scale applications require a lownoise, precision amplifier in front of an ADC. Figure details an example of a load cell and amplifier driven from the same V supply, along with a 6-bit delta sigma ADC such as the MAX. The MAX is an ultra-low-power (< 3FA, max active current), high-resolution, serial output ADC. It provides the highest resolution per unit power in the industry and is optimized for applications that require very high dynamic range with low power such as sensors on a 4 ma industrial control loop. The devices provide a high-accuracy internal oscillator that requires no external components. Layout Guidelines The MAX4444/MAX444/MAX4448 feature ultra-low input offset voltage and noise. Therefore, to get optimum performance follow the layout guidelines. Avoid temperature tradients at the junction of two dissimilar metals. The most common dissimilar metals used on a PCB are solder-to-component lead and solder-to-board trace. Dissimilar metals create a local thermocouple. A variation in temperature across the board can cause an additional offset due to Seebeck effect at the solder junctions. To minimize the Seebeck effect, place the amplifier away from potential heat sources on the board, if possible. Orient the resistors such that both the ends are heated equally. It is a good practice to match the input signal path to ensure that the type and number of thermoelectric juntions remain the same. For example, consider using dummy ω resistors oriented in such a way that the thermoelectric source, due to the real resistors in the signal path, are cancelled. It is recommended to flood the PCB with ground plane. The ground plane ensures that heat is distributed uniformly reducing the potential offset voltage degradation due to Seebeck effect. V ½ MAX4448 V AMP A V R F V IN+ V DD SCLK V DD MICRO- CONTROLLER SCK R G R F V V IN- RDY/DOUT MAX V SS MISO AMP B V SS ½ MAX4448 Figure. Weight Application

13 36V, Precision, Low-Power, 9µA, PROCESS: BiCMOS Chip Information Ordering Information Package Information For the latest package outline information and land patterns (footprints), go to Note that a +, #, or - in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PART TEMP RANGE PIN- PACKAGE TOP MARK MAX4444AUK+ -4 C to + C SOT3 AFMR MAX4444AUA+ -4 C to + C 8 µmax MAX444ASD+ -4 C to + C 4 SO MAX444AUD+ -4 C to + C 4 TSSOP MAX4448AUA+ -4 C to + C 8 µmax MAX4448ASA+ -4 C to + C 8 SO PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. SOT3 U SO S µmax U SO S4M TSSOP U4M Denotes a lead(pb)-free/rohs-compliant package. 3

14 36V, Precision, Low-Power, 9µA, Revision History REVISION NUMBER REVISION DATE DESCRIPTION PAGES CHANGED 7/ Initial release 6/3 9/3 Added the MAX4444/MAX444 to data sheet. Updated the Electrical Characteristics, Absolute Maximum Ratings, Pin Description, and Pin Configurations. Released the MAX4444 for introduction. Revised the Electrical Characteristics 3, 3 3 6/4 Corrected Figure and Package Information, 3 4 /4 Updated Benefits and Features section 9/ Updated Typical Operating Circuit cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a product. No circuit patent licenses are implied. reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. 6 Rio Robles, San Jose, CA 934 USA The Maxim logo and are trademarks of Products, Inc.

15 36V, Precision, Low-Power, 9µA,