- + 9-; Rev ; / Low-Cost, High-Slew-Rate, Rail-to-Rail I/O Op Amps in SC7 General Description The MAX9/MAX9/MAX9 single/dual/quad, low-cost CMOS op amps feature Rail-to-Rail input and output capability from either a single.7v to.v supply or dual ±.3V to ±.7V supplies. These amplifiers exhibit a high slew rate of V/µs and a gain-bandwidth product of MHz. They can drive kω resistive loads to within mv of either supply rail and remain unitygain stable with capacitive loads up to 3pF. The MAX9 is offered in the ultra-small, -pin SC7 package, which is % smaller than the standard -pin SOT3 package. Specifications for all parts are guaranteed over the automotive (- C to + C) temperature range. Applications Battery-Powered Instruments Portable Equipment Audio Signal Conditioning Low-Power/Low-Voltage Applications Sensor Amplifiers RF Power Amplifier Control High-Side/Low-Side Current Sensors Features.7V to.v Single-Supply Operation V/µs Slew Rate Rail-to-Rail Input Common-Mode Voltage Range Rail-to-Rail Output Voltage Swing MHz Gain-Bandwidth Product Unity-Gain Stable with Capacitive Loads Up to 3pF pa Input Bias Current Ultra-Small, -Pin SC7 Package (MAX9) PART Ordering Information TEMP RANGE PIN- PACKAGE SC7- SOT3-8 SOT3- TOP MARK MAX9AXK-T MAX9AUK-T MAX9AKA-T - C to + C - C to + C - C to + C AAB ADKQ AADB MAX9AUA - C to + C 8 µmax MAX9AUD - C to + C TSSOP MAX9ASD - C to + C SO MAX9/MAX9/MAX9 Capacitive-Load Stability Pin Configurations/ Functional Diagrams TOP VIEW CAPACITIVE LOAD (pf) 3 STABLE UNSTABLE k k k RESISTIVE LOAD (Ω) IN+ MAX9 V DD V SS IN- 3 SOT3-/SC7- Pin Configurations continued at end of data sheet. Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd. Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at -888-9-, or visit Maxim s website at www.maxim-ic.com.
Rail-to-Rail I/O Op Amps in SC7 MAX9/MAX9/MAX9 ABSOLUTE MAXIMUM RATINGS Supply Voltage (V DD to V SS )...V All Other Pins...(V SS -.3V) to (V DD +.3V) Output Short-Circuit Duration...s Continuous Power Dissipation (T A = +7 C) -Pin SC7 (derate.mw/ C above +7 C)... mw -Pin SOT3 (derate 7.mW/ C above +7 C)... 7mW 8-Pin SOT3 (derate.mw/ C above +7 C)... mw 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. ELECTRICAL CHARACTERISTICS 8-Pin µmax (derate.mw/ C above +7 C)... 33mW -Pin TSSOP (derate 8.3mW/ C above +7 C)... 7mW -Pin SO (derate 8.3mW/ C above +7 C)... 7mW Operating Temperature Range... - C to + C Junction Temperature... + C Storage Temperature Range... - C to + C Lead Temperature (soldering, s)... +3 C (, V SS =, V CM =, V = V DD /, R L = kω connected to V DD /, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = + C.) (Note ) Phase Margin Gain Margin Slew Rate PARAMETER Supply Voltage Range Supply Current (per amplifier) Input Offset Voltage Input Bias Current Input Offset Current Input Resistance Input Common-Mode Range Common-Mode Rejection Ratio Power-Supply Rejection Ratio Large-Signal Voltage Gain Output-Voltage Swing High Output-Voltage Swing Low Output Short-Circuit Current Gain-Bandwidth Product Input Capacitance Voltage-Noise Density Current-Noise Density Capacitive-Load Drive SYMBOL V DD I S V OS I B I OS R IN V CM CMRR PSRR A V V OH V OL I (SC) GBWP C IN SR e n i n (Note ) (Note 3) (Note 3) (Note 3) Inferred from CMRR test V SS V CM V DD.7V V DD.V (V SS +.V) V (V DD -.V) Specified as V DD - V OH Specified as V OL - V SS Sourcing or sinking C L = pf CONDITIONS T A = + C T A = T MIN to T MAX R L = kω R L = kω C L = pf C L = pf Measured from % to 9% of V P-P step ƒ = khz ƒ = khz A V(CL) =, no sustained oscillations MIN TYP MAX.7. V SS 7 8.8 ±. ± ± 3 ±. ±. ±. ±.. V DD R L = kω. 3 UNITS V ma mv na na MΩ V db db db mv mv ma MHz pf degrees db V/µs nv/ Hz fa Hz pf Note : All units production tested at T A = + C. Limits over temperature guaranteed by design. Note : Guaranteed by the Power-Supply Rejection Ratio (PSRR) test. Note 3: Input Offset Voltage, Input Bias Current, and Input Offset Current are all tested and guaranteed at both ends of the commonmode range.
Rail-to-Rail I/O Op Amps in SC7 SUPPLY CURRENT (µa) VDD - V (mv) GAIN (db) Typical Operating Characteristics (, V SS =, V CM = V DD /, R L = kω to V DD /, T A = + C, unless otherwise noted.) 8 8 7 7 8 7 3 3 SUPPLY CURRENT PER AMPLIFIER - - - 3 8 9 PUT SWING HIGH OR.7V R L = kω - - - 3 8 9 GAIN AND PHASE vs. FREQUENCY (WITH C LOAD ) MAX9 toc7 GAIN MAX9 toc MAX9 toc 8 3 PHASE -9 - A V = C LOAD = pf -3 - -8 k k k M M 9 - PHASE (DEGREES) SUPPLY CURRENT (µa) V - VSS (mv) LARGE-SIGNAL GAIN (db) 9 8 7 3 SUPPLY CURRENT PER AMPLIFIER vs. SUPPLY VOLTAGE.. 3. 3..... SUPPLY VOLTAGE (V) 8 7 3 3 9 8 PUT SWING LOW OR.7V R L = kω - - - 3 8 9 LARGE-SIGNAL GAIN - - - 3 8 9 MAX9 toc MAX9 toc MAX9 toc8 OFFSET VOLTAGE (mv) GAIN (db) PSSR (db) -. -. -. -.8 -. -. -. -. -.8 -. 3 - INPUT OFFSET VOLTAGE - - - 3 8 9 OP AMP GAIN AND PHASE vs. FREQUENCY A V = C L = pf PHASE GAIN MAX9 toc - -8 k k k M M - - -3 - - - -7-8 -9 - POWER-SUPPLY REJECTION RATIO vs. FREQUENCY A V = k k k M M MAX9 toc3 MAX9 toc9 8 3 9 - -9-3 PHASE (DEGREES) MAX9/MAX9/MAX9 3
Rail-to-Rail I/O Op Amps in SC7 MAX9/MAX9/MAX9 Typical Operating Characteristics (continued) (, V SS =, V CM = V DD /, R L = kω to V DD /, T A = + C, unless otherwise noted.) PUT IMPEDANCE (Ω) k.. IN V/div PUT IMPEDANCE vs. FREQUENCY A V = k k k M M LARGE-SIGNAL TRANSIENT RESPONSE (INVERTING) MAX9 toc MAX9toc3 THD + NOISE (%)..3.3..... IN mv/div TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY A V = V/V Vp-p SIGNAL khz LOWPASS FILTER k k k R L = kω SMALL-SIGNAL TRANSIENT RESPONSE (NONINVERTING) MAX9 toc MAX9toc IN V/div V/div IN mv/div LARGE-SIGNAL TRANSIENT RESPONSE (NONINVERTING) A V = µs/div SMALL-SIGNAL TRANSIENT RESPONSE (INVERTING) MAX9toc MAX9toc V/div mv/div mv/div A V = - µs/div A V = µs/div A V = - µs/div POWER-UP TRANSIENT RESPONSE MAX9toc SLEW RATE vs. SUPPLY VOLTAGE MAX9 toc7 - MAX9/MAX9 CROSSTALK vs. FREQUENCY MAX9toc8 V DD V/div SLEW RATE (V/µS) 8 CROSSTALK (db) - - -8 V/div A V = % TO 9% STEP - µs/div A V =, V IN CONNECTED TO V DD /,. 3. 3..... SUPPLY VOLTAGE (V) -... FREQUENCY (MHz)
Rail-to-Rail I/O Op Amps in SC7 MAX9 PIN MAX9 MAX9 NAME IN+ Noninverting Input FUNCTION V SS Negative Supply Input. Connect to ground for single-supply operation. 3 IN- Inverting Input Amplifier Output 8 V DD Positive Supply Input 3 3 INA+ Noninverting Input to Amplifier A INA- Inverting Input to Amplifier A A Amplifier A Output INB+ Noninverting Input to Amplifier B INB- Inverting Input to Amplifier B 7 7 B Amplifier B Output, INC+, IND+ Noninverting Inputs to Amplifiers C and D 9, 3 INC-, IND- Inverting Inputs to Amplifiers C and D 8, C, D Amplifiers C and D Outputs Detailed Description Rail-to-Rail Input Stage The MAX9/MAX9/MAX9 CMOS operational amplifiers have parallel-connected N- and P-channel differential input stages that combine to accept a common-mode range extending to both supply rails. The N- channel stage is active for common-mode input voltages typically greater than (V SS +.V), and the P- channel stage is active for common-mode input voltages typically less than (V DD -.V). Rail-to-Rail Output Stage The MAX9/MAX9/MAX9 CMOS operational amplifiers feature class-ab push-pull output stages that can drive a kω load to within.mv of either supply rail. Short-circuit output current is typically ±ma. Figures a and b show the typical temperature dependence of output source and sink currents, respectively, for three fixed values of (VDD - VOH) and (VOL - V SS ). For example, at VDD =.V, the load currents that maintain (V DD - V OH ) = mv and (V OL - V SS ) = mv at TA = + C are.ma and 3.3mA, respectively, when Pin Description the load is connected to VDD/. Consistent resistivedrive capability is (. -.) /. =.kω. For the same application, resistive-drive capability is.kω when the load is connected to VDD or VSS. Applications Information Power-Supply Considerations The MAX9/MAX9/MAX9 operate from a single.7v to.v supply or from dual ±.3V to ±.7V supplies with typically 8µA supply current per amplifier. A high power-supply rejection ratio of db allows for extended operation from a decaying battery voltage, thereby simplifying designs for portable applications. For single-supply operation, bypass the power supply with a.µf ceramic capacitor placed close to the V DD pin. For dual-supply operation, bypass each supply to ground. Input Capacitance One consequence of the parallel-connected differential input stages for rail-to-rail operation is a relatively large input capacitance C IN (typically pf). This introduces a MAX9/MAX9/MAX9
Rail-to-Rail I/O Op Amps in SC7 MAX9/MAX9/MAX9 pole at frequency (πr C IN )-, where R is the parallel combination of the gain-setting resistors for the inverting or noninverting amplifier configuration (Figure ). If the pole frequency is less than or comparable to the unity-gain bandwidth (MHz), the phase margin will be reduced, and the amplifier will exhibit degraded AC performance through either ringing in the step response or sustained oscillations. The pole frequency is MHz when R = 3.kΩ. To maximize stability, R <3kΩ is recommended. Applications that require rail-to-rail operation with minimal loading (for small V DD - V OH and V OL - V SS ) will typically require R values >3kΩ. To improve step response under these conditions, connect a small PUT SOURCE CURRENT (ma) 3 V DD - V OH = mv V DD - V OH = mv V DD - V OH = mv - - - 3 8 9 capacitor C f between the inverting input and output. Choose C f as follows: C f = (R / R f ) [pf] where Rf is the feedback resistor and R is the gain-setting resistor (Figure ). Figure 3 shows the step response for a noninverting amplifier subject to R = kω with and without the C f feedback capacitor. INVERTING V IN R C f R f MAX9 R = R R f R f C f = RC IN V Figure a. Output Source Current vs. Temperature NONINVERTING V IN PUT SINK CURRENT (ma) 9 8 7 3 V DD - V OH = mv V DD - V OH = mv V DD - V OH = mv R MAX9 R f C f R = R R f R f C f = RC IN V - - - 3 8 9 Figure b. Output Sink Current vs. Temperature Figure. Inverting and Noninverting Amplifier with Feedback Compensation
Rail-to-Rail I/O Op Amps in SC7 Driving Capacitive Loads In conjunction with op amp output resistance, capacitive loads introduce a pole frequency that can reduce phase margin and lead to unstable operation. The MAX9/MAX9/MAX9 drive capacitive loads up to 3pF without significant degradation of step response and slew rate (Figure ). Capacitive-Load Stability (page ) shows regions of stable and marginally stable (step overshoot <%) operation for different combinations of capacitive and resistive loads. 3a) 3b) WITH FEEDBACK COMPENSATION A V = -, R L = kω, C f = Improve stability for large capacitive loads by adding an isolation resistor (typically Ω) in series with the output (Figure ). Note that the isolation resistor forms a voltage divider with potential for gain error. MAX9 TRANSISTOR COUNT: MAX9 TRANSISTOR COUNT: MAX9 TRANSISTOR COUNT: SUBSTRATE CONNECTED TO VSS a) b) WITH CAPACITIVE LOADING A V = +, R L = kω, C L = Chip Information MAX9/MAX9/MAX9 WITH FEEDBACK COMPENSATION A V = -, R L = kω, C f = pf WITH CAPACITIVE LOADING A V = +, R L = kω, C L = 3pF Figure 3. Step Response With and Without Feedback Compensation Figure. Step Response With and Without Capacitive Loading 7
Rail-to-Rail I/O Op Amps in SC7 MAX9/MAX9/MAX9 V IN R S V MAX9 C LOAD Figure. Isolation Resistor for Large Capacitive Loads Pin Configurations/ Functional Diagrams (continued) TOP VIEW A INA+ V SS 3 MAX9 SOT3-8/µMAX 8 7 V DD D 3 IND- IND+ V SS INC+ 9 INC- 8 C A INA- INA+ 3 V DD INB+ INB- B 7 MAX9 B INB- INB+ INA- Package Information TSSOP/SO SC7, L.EPS 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. 8 Maxim Integrated Products, San Gabriel Drive, Sunnyvale, CA 98 8-737-7 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.