19-1295; Rev 3; 8/01 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps The MAX4249–MAX4257 low-noise, low-distortion operational amplifiers offer Rail-to-Rail® outputs and singlesupply operation down to 2.4V. They draw 400µA of quiescent supply current per amplifier while featuring ultra-low distortion (0.0002% THD), as well as low input voltage noise density (7.9nv/√Hz) and low input current noise density (0.5fA/√Hz). These features make the devices an ideal choice for portable/battery-powered applications that require low distortion and/or low noise. For additional power conservation, the MAX4249/4251/ 4253/4256 offer a low-power shutdown mode that reduces supply current to 0.5µA and puts the amplifiers’ outputs into a high-impedance state. The MAX4249-MAX4257’s outputs swing rail-to-rail and their input common-mode voltage range includes ground. The MAX4250–MAX4254 are unity-gain stable with a gain-bandwidth product of 3MHz. The MAX4249/ MAX4255/MAX4256/MAX4257 are internally compensated for gains of +10V/V or greater with a gain-bandwidth product of 22MHz. The single MAX4250/ MAX4255 are available in space-saving, 5-pin SOT23 packages. The MAX4252 is available in an 8-pin UCSP package and the MAX4253 is available in a 10-pin UCSP package. Features ♦ Available in Space-Saving UCSP™, SOT23, and µMAX Packages ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ Low Distortion: 0.0002% THD (1kΩ load) 400µA Quiescent Supply Current per Amplifier Single-Supply Operation from +2.4V to +5.5V Input Common-Mode Voltage Range Includes Ground Outputs Swing Within 8mV of Rails with a 10kΩ Load 3MHz GBW Product, Unity-Gain Stable (MAX4250–MAX4254) 22MHz GBW Product, Stable with AV ≥ 10V/V (MAX4249/MAX4255/MAX4256/MAX4257) Excellent DC Characteristics VOS = 70µV IBIAS = 1pA Large-Signal Voltage Gain = 116dB Low-Power Shutdown Mode: Reduces Supply Current to 0.5µA Places Outputs in a High-Impedance State 400pF Capacitive-Load Handling Capability Applications Wireless Communications Devices PA Control Ordering Information TEMP. RANGE PIN/BUMPPACKAGE MAX4249ESD -40°C to +85°C 14 SO — MAX4249EUB -40°C to +85°C 10 µMAX — MAX4250EUK-T -40°C to +85°C 5 SOT23-5 PART Portable/Battery-Powered Equipment Medical Instrumentation ADC Buffers Digital Scales/Strain Gauges Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd. UCSP is a trademark of Maxim Integrated Products, Inc. TOP MARK ACCI Ordering Information continued at end of data sheet. Selector Guide appears at end of data sheet. Pin Configurations TOP VIEW (BUMPS ON BOTTOM) MAX4253 MAX4252 1 A OUTA B INA- C INA+ 2 VDD 3 OUTB INB- VSS INB+ A1 A2 A3 OUTB INB- INB+ A4 B1 SHDNB B4 VDD VSS C1 C2 C3 OUTA INA- INA+ C4 SHDNA UCSP UCSP Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX4249–MAX4257 General Description MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps ABSOLUTE MAXIMUM RATINGS Power-Supply Voltage (VDD to VSS) ......................+6.0V to -0.3V Analog Input Voltage (IN_+, IN_-)....(VDD + 0.3V) to (VSS - 0.3V) SHDN Input Voltage....................................+6.0V to (VSS - 0.3V) Output Short-Circuit Duration to Either Supply ..........Continuous Continuous Power Dissipation (TA = +70°C) 5-Pin SOT23 (derate 7.1mW/°C above +70°C)...........571mW 8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW 8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW 8-Pin UCSP (derate 4.7mW/°C above +70°C) ............379mW 10-Pin UCSP (derate 6.1mW/°C above +70°C) ...........484mW Note 1: 10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW 14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Bump Temperature (soldering) (Note 1) Infrared (15s) ................................................................+220°C Vapor Phase (60s) ........................................................+215°C This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device can be exposed to during board-level solder attach and rework. This limit permits only the use of the solder profiles recommended in the industry-standard specification, JEDEC 020A, paragrah 7.6, Table 3 for IR/VPR and Convection Reflow. Preheating is required. Hand or wave soldering is not allowed. 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 (VDD = +5V, VSS = 0, VCM = 0, VOUT = VDD/2, RL tied to VDD/2, SHDN = VDD, TA = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C.) (Notes 2, 3) PARAMETER Supply Voltage Range Quiescent Supply Current per Amplifier SYMBOL VDD CONDITIONS (Note 4) MIN TYP 2.4 UNITS 5.5 V VDD = +3V 400 VDD = +5V 420 575 VDD = +5V, UCSP only 420 655 Shutdown mode (SHDN = VSS) (Note 2) 0.5 1.5 ±0.75 Normal mode IQ µA Input Offset Voltage (Note 5) VOS ±0.07 Input Offset Voltage Tempco TCVOS 0.3 Input Bias Current MAX mV µV/°C IB (Note 6) ±1 ±100 pA Input Offset Current IOS (Note 6) ±1 ±100 pA Differential Input Resistance RIN Input Common-Mode Voltage Range VCM 1000 Guaranteed by CMRR Test -0.2 GΩ VDD - 1.1 V Common-Mode Rejection Ratio CMRR VSS - 0.2V ≤ VCM ≤ VDD - 1.1V 70 115 dB Power-Supply Rejection Ratio PSRR VDD = 2.4 to 5.5V 75 100 dB RL = 10kΩ to VDD/2; VOUT = 25mV to VDD - 4.97V 80 116 RL = 1kΩ to VDD/2; VOUT = 150V to VDD - 4.75V 80 112 Large-Signal Voltage Gain Output Voltage Swing 2 AV VOUT |VIN+ - VIN-| ≥ 10mV RL = 10kΩ to VDD/2 dB VDD – VOH 8 25 VOL - VSS 7 20 _______________________________________________________________________________________ mV UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps (VDD = +5V, VSS = 0, VCM = 0, VOUT = VDD/2, RL tied to VDD/2, SHDN = VDD, TA = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C) (Notes 2, 3) PARAMETER Output Voltage Swing Output Short-Circuit Current Output Leakage Current SYMBOL VOUT CONDITIONS |VIN+ - VIN-| ≥ 10mV, RL = 1kΩ to VDD/2 TYP MAX VDD – VOH 77 200 VOL - VSS 47 100 ISC ILEAK 68 Shutdown mode (SHDN = VSS), VOUT = VSS to VDD (Note 2) SHDN Logic Low VIL (Note 2) SHDN Logic High VIH (Note 2) SHDN Input Current IIL/IIH SHDN = VSS = VDD (Note 2) Slew Rate GBW SR Peak-to-Peak Input Noise Voltage Input Voltage Noise Density Input Current Noise Density en(p-p) en in 0.5 MAX4250–MAX4254 3 MAX4249/MAX4255/MAX4256/MAX4257 22 MAX4250–MAX4254 0.3 MAX4249/MAX4255/MAX4256/MAX4257 2.1 f = 0.1Hz to 10Hz 760 f = 10Hz 2.7 f = 1kHz 8.9 f = 30kHz 7.9 f = 1kHz 0.5 MAX4250–MAX4254 AV = +1V/V, VOUT = 2Vp-p, RL = 1kΩ to GND (Note 7) Total Harmonic Distortion Plus Noise THD+N Capacitive-Load Stability GM ΦM MAX4249/MAX4255/ MAX4256/MAX4257 AV = +1V/V, VOUT = 2Vp-p, RL = 1kΩ to GND (Note 7) mV 1.0 µA 0.2 X VDD V V 11 Gain Bandwidth Product Phase Margin 0.001 UNITS mA 0.8 X VDD Input Capacitance Gain Margin MIN 1.5 µA pF MHz V/µs f = 1kHz 0.0004 f = 20kHz 0.006 f = 1kHz 0.0012 f = 20kHz 0.007 nVp-p nV/√Hz fA/√Hz % No sustained oscillations 400 MAX4250–MAX4254, AV = +1V/V 10 MAX4249/MAX4255/MAX4256/MAX4257, AV = +10V/V pF dB 12.5 MAX4250–MAX4254, AV = +1V/V 74 MAX4249/MAX4255/MAX4256/MAX4257, AV = +10V/V 68 degrees _______________________________________________________________________________________ 3 MAX4249–MAX4257 ELECTRICAL CHARACTERISTICS (continued) MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps ELECTRICAL CHARACTERISTICS (continued) (VDD = +5V, VSS = 0, VCM = 0, VOUT = VDD/2, RL tied to VDD/2, SHDN = VDD, TA = -40°C to +125°C, unless otherwise noted. Typical values are at TA = +25°C) (Notes 2, 3) PARAMETER SYMBOL To 0.01%, VOUT = 2V step Settling Time Delay Time to Shutdown Delay Time to Enable Power-Up Delay Time CONDITIONS tSH tEN tPU IVDD = 5% of normal operation VOUT = 2.5V, VOUT settles to 0.1% MIN TYP MAX4250–MAX4254 6.7 MAX4249/MAX4255/ MAX4256/MAX4257 1.6 MAX4251/MAX4253 0.8 MAX4249/MAX4256 1.2 MAX4251/MAX4253 8 MAX4249/MAX4256 3.5 MAX µs µs µs VDD = 0 to 5V step, VOUT stable to 0.1% 6 Note 2: SHDN is available on the MAX4249/MAX4251/MAX4253/MAX4256 only. Note 3: All device specifications are 100% tested at TA = +25°C. Limits over temperature are guaranteed by design. Note 4: Guaranteed by the PSRR test. Note 5: Offset voltage prior to reflow on UCSP. Note 6: Guaranteed by design. Note 7: Lowpass-filter bandwidth is 22kHz for f = 1kHz and 80kHz for f = 20kHz. Noise floor of test equipment = 10nV/√Hz. 4 UNITS _______________________________________________________________________________________ µs UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps (VDD = +5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements, TA = +25°C, unless otherwise noted.) 100 25 20 0 -50 15 -100 10 -150 -200 0 -250 -95 -75 -55 -35 -13 7 28 49 69 90 110 131 152 172 192 5 -20 0 20 40 MAX4249 TOC03 1.5 2.5 3.5 OUTPUT VOLTAGE SWING (VOL) vs. TEMPERATURE 0.09 RL = 1kΩ 0.08 0.05 0.07 0.2 0.05 0.02 0.02 RL = 10kΩ 0.01 0.01 3 4 5 6 7 8 9 0 -40 10 RL = 10kΩ RL = 100kΩ RL = 100kΩ 0 2 0.03 0.04 0.03 0 RL = 1kΩ 0.04 0.06 VOL (V) VDD - VOH (V) VOL -20 0 20 40 60 80 -40 -20 0 20 40 60 TEMPERATURE (°C) TEMPERATURE (°C) LARGE-SIGNAL VOLTAGE GAIN vs. OUTPUT VOLTAGE SWING LARGE-SIGNAL VOLTAGE GAIN vs. OUTPUT VOLTAGE SWING LARGE-SIGNAL VOLTAGE GAIN vs. OUTPUT VOLTAGE SWING 130 AV (dB) 90 100 90 80 110 RL = 200kΩ RL = 20kΩ 110 100 RL = 2kΩ 70 50 100 150 200 VOUT SWING FROM EITHER SUPPLY (mV) VDD = +3V RL REFERENCED TO VDD 60 50 250 RL = 2kΩ 90 70 70 VDD = +3V RL REFERENCED TO GND RL = 20kΩ 100 80 80 60 120 120 RL = 2kΩ RL = 200kΩ 130 AV (dB) RL = 20kΩ 110 140 MAX4249 TOC08 120 140 MAX4249TOC07 130 RL = 200kΩ 80 MAX4249TOC09 OUTPUT LOAD CURRENT (mA) 140 4.5 0.06 MAX4249 TOC05 0.10 MAX4249 TOC04 0.3 0 0.5 OUTPUT VOLTAGE SWING (VOH) vs. TEMPERATURE 0.4 1 0 -50 -0.5 80 VDD = +5V OUTPUT VOLTAGE vs. OUTPUT LOAD CURRENT VDD - VOH 0 VDD = +3V 50 INPUT COMMON-MODE VOLTAGE (V) 0.1 AV (dB) 60 100 TEMPERATURE (°C) VDD = +3V OR +5V VDIFF = ±10mV 0.5 -40 150 VOS (µV) 0.6 OUTPUT VOLTAGE (V) 50 200 MAX4249 TOC06 150 VOS (µV) NUMBER OF UNITS 30 VCM = 0 200 INPUT OFFSET VOLTAGE (µV) 35 MAX4249 TOC02 400 UNITS VCM = 0 TA = +25°C INPUT OFFSET VOLTAGE vs. COMMON-MODE INPUT VOLTAGE 250 MAX4249 TOC01 40 OFFSET VOLTAGE vs. TEMPERATURE MAX4251/MAX4256 INPUT OFFSET VOLTAGE DISTRIBUTION 0 50 100 150 200 VOUT SWING FROM EITHER SUPPLY (mV) VDD = +5V RL REFERENCED TO GND 60 50 250 0 50 100 150 200 250 VOUT SWING FROM EITHER SUPPLY (mV) _______________________________________________________________________________________ 5 MAX4249–MAX4257 Typical Operating Characteristics Typical Operating Characteristics (continued) (VDD = +5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements, TA = +25°C, unless otherwise noted.) MAX4249 TOC11 RL = 20kΩ 130 120 RL REFERENCED T0 VDD/2 VDD = +5V RL = 2kΩ 110 115 AV (dB) 100 RL = 100kΩ VOUT = 10mV to 4.99V 110 90 80 70 105 VDD = +5V RL REFERENCED TO VDD 60 50 50 100 150 200 250 400 SHDN = VDD 0.374 380 RL = 10kΩ VOUT = 20mV TO 4.975V 360 0.373 340 -40 -20 0 20 40 60 -40 80 -20 0 20 40 60 TEMPERATURE (°C) TEMPERATURE (°C) SUPPLY CURRENT AND SHUTDOWN SUPPLY CURRENT vs. SUPPLY VOLTAGE SUPPLY CURRENT vs. OUTPUT VOLTAGE INPUT OFFSET VOLTAGE vs. SUPPLY VOLTAGE SHDN = VSS 0.3 360 0.2 340 0.1 320 2.3 2.8 3.3 3.8 4.3 4.8 MAX4249 TOC14 VDD = +5V 100 0.001 5.3 5.5 180 VDD = +3V, +5V 144 RL = 50k Ω CL = 20pF 108 AV = 1000 72 40 0.01 36 0 10 -36 0 -10 PHASE -20 0.1 1 1.8 5 50 40 30 VDD = +3V, +5V RL = 50k Ω CL = 20pF AV = 1000 GAIN 180 0 144 -10 108 -20 72 20 36 10 0 -36 0 PHASE -72 -10 -108 -20 -108 -90 -144 -100 -180 10M -110 FREQUENCY (Hz) 10k 100k FREQUENCY (Hz) 1M MAX4249 TOC18 PSRR+ -80 -30 1k 5.3 -70 -72 100 4.8 VDD = +3V, +5V -60 -40 1M 4.3 -50 -180 10M 100k 3.8 -40 -144 10k 3.3 -30 -40 1k 2.8 MAX4250–MAX4254 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY -30 100 2.3 SUPPLY VOLTAGE (V) MAX4249 TOC17 60 GAIN (dB) GAIN 20 RL = 100kΩ MAX4249/MAX4255/MAX4256/MAX4257 GAIN AND PHASE vs. FREQUENCY PHASE (DEGREES) 30 80 OUTPUT VOLTAGE (V) MAX4249 TOC16 40 RL = 1kΩ 60 MAX4250–MAX4254 GAIN AND PHASE vs. FREQUENCY 50 RL = 10kΩ 100 VDD = +3V SUPPLY VOLTAGE (V) 60 120 400 0 1.8 140 1000 PSRR (dB) 380 VCM = 0 VOUT = VDD/2 RL REFERENCED TO GND 160 VOS (µV) 0.4 SUPPLY CURRENT (µA) 0.5 SHDN = VDD 180 2000 SHUTDOWN SUPPLY CURRENT (µA) 420 80 MAX4249 TOC15 0.6 PER AMPLIFIER 400 0.375 420 VOUT SWING FROM EITHER SUPPLY (mV) MAX4249 TOC13 440 6 440 100 0 SUPPLY CURRENT (µA) RL = 1kΩ VOUT = 150mV TO 4.75V 0.376 PER AMPLIFIER SHDN = VSS PHASE (DEGREES) AV (dB) 120 MAX4249 TOC12 460 SUPPLY CURRENT (µA) RL = 200kΩ 140 125 MAX4249 TOC10 150 SUPPLY CURRENT AND SHUTDOWN SUPPLY CURRENT vs. TEMPERATURE LARGE-SIGNAL VOLTAGE GAIN vs. TEMPERATURE PSRR- 1 10 100 1k 10k 100k FREQUENCY (Hz) _______________________________________________________________________________________ 1M 10M SHUTDOWN SUPPLY CURRENT (µA) LARGE-SIGNAL VOLTAGE GAIN vs. OUTPUT VOLTAGE SWING GAIN (dB) MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps (VDD = +5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements, TA = +25°C, unless otherwise noted.) INPUT VOLTAGE N0ISE DENSITY vs. FREQUENCY 1 AV = +1 (MAX4250–MAX4254) 0.1 1k 10k 100k 1M 10 10M 100 1k 10k -60 fO -100 HD2 HD4 VIN -40 -140 VO RL VO 10kΩ 100kΩ 11kΩ 11kΩ 0.1 100kΩ RL = 1kΩ -80 HD2 -100 HD5 AV = +10 VIN fO = 3kHz FILTER BW = 30kHz 1 fO -60 10 THD+N (%) -20 MAX4250–MAX4254 THD PLUS NOISE vs. OUTPUT VOLTAGE (VDD = 5V) MAX4249 TOC23 VOUT = 4Vp-p fO = 1kHz 0 1s/div 100k 20 MAX4249 TOC22 RL = 1k Ω fO = 1kHz AV = +1 AMPLITUDE (dBc) 0.01 HD3 RL = 10kΩ -120 -160 -140 10 5k 10k 15k 20k 5k 15k 10k 20k 0 4 5 MAX4250–MAX4254 THD PLUS NOISE vs. OUTPUT VOLTAGE SWING (VDD = 3V) MAX4249/MAX4255/MAX4256/MAX4257 THD PLUS NOISE vs. OUTPUT VOLTAGE SWING MAX4250–MAX4254 THD PLUS NOISE vs. FREQUENCY AV = +10 RL 100kΩ 11kΩ 0.1 RL = 1kΩ VIN VOUT THD+N (%) 11kΩ 1 MAX4249 TOC25 RL 1 1 VIN VOUT RL 0.1 100kΩ fO = 20kHz, FILTER BW = 80kHz R1 AV = +10 VDD = +3V fO = 3kHz FILTER BW = 30kHz 1 AV = 10 0.001 RL = 100kΩ FILTER BW= 22kHz RL = 10kΩ TO GND VO = 2Vp-p AV = 1 fO = 3kHz, FILTER BW = 30kHz 0.001 OUTPUT VOLTAGE (Vp-p) AV = 100 R1 = 560Ω, R2 = 53kΩ R1 = 5.6kΩ, R2 = 53kΩ RL = 10kΩ 2 R2 0.01 0.01 0 3 OUTPUT VOLTAGE (Vp-p) VOUT 0.001 2 FREQUENCY (Hz) VIN 0.01 1 FREQUENCY (Hz) 10 0.1 RL = 100kΩ 0.001 10 THD+N (%) AMPLITUDE (dBc) Vp-p NOISE = 760nVp-p 0 MAX4249/MAX4255/MAX4256/MAX4257 FFT OF DISTORTION AND NOISE HD3 THD+N (%) 5 MAX4250–MAX4254 FFT OF DISTORTION AND NOISE -40 -120 10 FREQUENCY (Hz) VOUT = 2Vp-p -80 200nV/ div 15 FREQUENCY (Hz) 0 -20 20 MAX4249 TOC24 10 25 MAX4249 TOC27 100 MAX4249 TOC21 VDD = 3V OR 5V MAX4249 TOC26 OUTPUT IMPEDANCE (Ω) AV = +10 (MAX4249/MAX4255/ MAX4256/MAX4257) 0.1Hz TO 10Hzp-p NOISE 30 MAX4249 TOC20 MAX4249 TOC19 1000 Vn-EQUIVALENT INPUT NOISE VOLTAGE (nV/√Hz) OUTPUT IMPEDANCE vs. FREQUENCY 3 0.0001 0 1 2 3 OUTPUT VOLTAGE (Vp-p) 4 5 10 100 1k 10k FREQUENCY (Hz) _______________________________________________________________________________________ 7 MAX4249–MAX4257 Typical Operating Characteristics (continued) Typical Operating Characteristics (continued) (VDD = +5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements, TA = +25°C, unless otherwise noted.) MAX4250–MAX4254 LARGE-SIGNAL PULSE RESPONSE MAX4250–MAX4254 THD PLUS NOISE vs. FREQUENCY FILTER BW = 80kHz AV = +1 RL = 1kΩ VOUT = 2Vp-p MAX4250–MAX4254 SMALL-SIGNAL PULSE RESPONSE MAX4249 TOC29 MAX4249 TOC28 0.1 THD PLUSE NOISE (%) MAX4249 TOC30 1.5V 0.6V VOUT 20mV/ div 0.01 RL TO VDD/2 RL TO GND VOUT 200mV/ div RL TO VDD 0.5V 0.001 VDD = +3V RL = 10kΩ CL = 100pF VIN = 1V PULSE 0.5V VDD = +3V RL = 10kΩ CL = 100pF VIN = 100mV PULSE 0.0001 10 100 1k 2µs/div 10k 2µs/div FREQUENCY (Hz) MAX4249/MAX4255/MAX4256/MAX4257 SMALL-SIGNAL PULSE RESPONSE CHANNEL SEPARATION vs. FREQUENCY MAX4249 TOC32 MAX4249 TOC31 140 130 2V 1.6V VOUT 200mV/ div 1V MAX4249 TOC33 MAX4249/MAX4255/MAX4256/MAX4257 LARGE-SIGNAL PULSE RESPONSE VDD = +3V RL = 10kΩ CL = 100pF VIN = 100mV PULSE AV = +10 2µs/div VOUT 50mV/div 1.5V VDD = +3V RL = 10kΩ CL = 100pF VIN = 10mV PULSE AV = +10 2µs/div CHANNEL SEPARATION (dB) MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps 120 110 100 90 80 70 0 1k 10k 100k FREQUENCY (Hz) 8 _______________________________________________________________________________________ 1M 10M UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps PIN MAX4250/ MAX4255 MAX4251/ MAX4256 MAX4252/ MAX4257 MAX4252 5 SOT23 8 SO/ µMAX 8 SO/ µMAX 8 UCSP 10 UCSP A1, A3 A1, C1 1 6 1, 7 MAX4249/ MAX4253 10 µMAX 1, 9 MAX4254 14 SO 1, 13 NAME FUNCTION OUT, OUTA, OUTB, OUTC, OUTD Amplifier Output 14 SO 1, 7, 8, 14 2 4 4 C2 B4 4 4 11 VSS Negative Supply. Connect to ground for single-supply operation 3 3 3, 5 C1, C3 A3, C3 3, 5 3, 11 3, 5, 10, 12 IN+, INA+, INB+, INC+, IND+ Noninverting Amplifier Input 4 2 2, 6 B1, B3 A2, C2 2, 6 2, 12 2, 6, 9, 13 IN-, INA-, INB-, INC-, IND- Inverting Amplifier Input 5 7 8 A2 B1 8 14 4 VDD Positive Supply — 8 — — A4, C4 — 5, 9 — SHDN, SHDNA, SHDNB — 1, 5 — — — — 5, 7, 8, 10 — N.C. — — — B2 B2, B3 — — — — Detailed Description The MAX4249–MAX4257 single-supply operational amplifiers feature ultra-low noise and distortion while consuming very little power. Their low distortion and low noise make them ideal for use as preamplifiers in wide dynamic-range applications, such as 16-bit analog-to-digital converters (see Typical Operating Circuit). Their high-input impedance and low noise are also useful for signal conditioning of high-impedance sources, such as piezoelectric transducers. These devices have true rail-to-rail ouput operation, drive loads as low as 1kΩ while maintining DC accuracy, and can drive capactive loads up to 400pF without Shutdown Input, Connect to VDD or leave unconnected for normal operation (amplifier(s) enabled). No Connection. Not internally connected. Not populated with solder sphere oscillation. The input common-mode voltage range extends from VDD - 1.1V to 200mV beyond the negative rail. The push/pull output stage maintains excellent DC characteristics, while delivering up to ±5mA of current. The MAX4250–4254 are unity-gain stable, whereas, the MAX4249/MAX4255/MAX4256/MAX4257 have a higher slew rate and are stable for gains ≥ 10V/V. The MAX4249/MAX4251/MAX4253/MAX4256 feature a lowpower shutdown mode, which reduces the supply current to 0.5µA and disables the outputs. Low Distortion Many factors can affect the noise and distortion that the device contributes to the input signal. The following _______________________________________________________________________________________ 9 MAX4249–MAX4257 Pin Description MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps guidelines offer valuable information on the impact of design choices on Total Harmonic Distortion (THD). Choosing proper feedback and gain resistor values for a particular application can be a very important factor in reducing THD. In general, the smaller the closedloop gain, the smaller the THD generated, especially when driving heavy resistive loads. Large-value feedback resistors can significantly improve distortion. The THD of the part normally increases at approximately 20dB per decade, as a function of frequency. Operating the device near or above the full-power bandwidth significantly degrades distortion. Referencing the load to either supply also improves the part’s distortion performance, because only one of the MOSFETs of the push/pull output stage drives the output. Referencing the load to mid-supply increases the part’s distortion for a given load and feedback setting. (See the Total Harmonic Distortion vs. Frequency graph in the Typical Operating Characteristics.) For gains ≥ 10V/V, the decompensated devices MAX4249/MAX4255/MAX4256/MAX4257 deliver the best distortion performance, since they have a higher slew rate and provide a higher amount of loop gain for a given closed-loop gain setting. Capacitive loads below 400pF, do not significantly affect distortion results. Distortion performance remains relatively constant over supply voltages. CZ RF RG VOUT VIN Figure 1. Adding Feed-Forward Compensation AV = +2V/V RF = RG = 100kΩ 100mV VIN 50mV/div 0 VOUT 100mV/div Low Noise The amplifier’s input-referred noise voltage density is dominated by flicker noise at lower frequencies, and by thermal noise at higher frequencies. Because the thermal noise contribution is affected by the parallel combination of the feedback resistive network (R F || R G , Figure 1), these resistors should be reduced in cases where the system bandwidth is large and thermal noise is dominant. This noise contribution factor decreases, however, with increasing gain settings. For example, the input noise voltage density of the circuit with RF = 100kΩ, RG = 11kΩ (AV = 10V/V) is en = 15nV/√Hz, en can be reduced to 9nV/√Hz by choosing RF = 10kΩ, RG = 1.1kΩ (AV = 10V/V), at the expense of greater current consumption and potentially higher distortion. For a gain of 100V/V with RF = 100kΩ, RG = 1.1kΩ, the en is low (9nV/√Hz). 2µs/div Figure 2a. Pulse Response with No Feed-Forward Compensation 100mV AV = +2 RF = RG = 100kΩ CZ = 11pF VIN 50mV/div 0 VOUT 100mV/div Using a Feed-Forward Compensation Capacitor, CZ The amplifier’s input capacitance is 11pF. If the resistance seen by the inverting input is large (feedback network), this can introduce a pole within the amplifier’s bandwidth, resulting in reduced phase margin. 10 2µs/div Figure 2b. Pulse Response with 10pF Feed-Forward Compensation ______________________________________________________________________________________ UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps RISO VOUT CL MAX4250 MAX4251 MAX4252 MAX4253 MAX4254 VIN Figure 3. Overdriven Input Showing No Phase Reversal AV = +1 4.25V VDD = +5V RL = 10kΩ VOUT 0 4.45V VIN -200mV 0 CZ = 11 x (RF / RG) [pF] In the unity-gain stable MAX4250–MAX4254, the use of a proper CZ is most important for AV = +2V/V, and AV = -1V/V. In the decompensated MAX4249/MAX4255/ MAX4256/MAX4257, CZ is most important for AV = +10V/V. Figures 2a and 2b show transient response both with and without CZ. Using a slightly smaller CZ than suggested by the formula above achieves a higher bandwidth at the expense of reduced phase and gain margin. As a general guideline, consider using CZ for cases where RG || R F is greater than 20kΩ (MAX4250–MAX4254) or greater than 5kΩ (MAX4249/MAX4255/MAX4256/ MAX4257). Applications Information The MAX4249–MAX4257 combine good driving capability with ground-sensing input and rail-to-rail output operation. With their low distortion, low noise and lowpower consumption, these devices are ideal for use in portable instrumentation systems and other low-power, noise-sensitive applications. Ground-Sensing and Rail-to-Rail Outputs The common-mode input range of these devices extends below ground, and offers excellent commonmode rejection. These devices are guaranteed not to undergo phase reversal when the input is overdriven (Figure 3). 20µs/div Figure 4. Rail-to-Rail Output Operation AV = +1 4.25V VDD = +5V RL = 10kΩ VOUT 0 Figure 4 showcases the true rail-to-rail output operation of the amplifier, configured with AV = 10V/V. The output swings to within 8mV of the supplies with a 10kΩ load, making the devices ideal in low-supply-voltage applications. Output Loading and Stability 4.45V VIN -200mV 0 20µs/div Figure 5. Capacitive-Load Driving Circuit Even with their low quiescent current of 400µA, these amplifiers can drive 1kΩ loads while maintaining excellent DC accuracy. Stability while driving heavy capacitive loads is another key feature. These devices maintain stability while driving loads up to 400pF. To drive higher capacitive loads, place a small isolation resistor in series between the output of the amplifier and the capacitive load (Figure 5). This resistor improves the amplifier’s phase margin by isolating the capacitor from the op amp’s output. ______________________________________________________________________________________ 11 MAX4249–MAX4257 Compensate the reduced phase margin by introducing a feed-forward capacitor (CZ) between the inverting input and the output (Figure 1). This effectively cancels the pole from the inverting input of the amplifier. Choose the value of CZ as follows: 4.5 140 4.0 UNITY-GAIN BANDWIDTH (MHz) 160 RISO (Ω) 120 100 80 60 SHADED AREA INDICATES STABLE OPERATION WITH NO NEED FOR ISOLATION RESISTOR. 40 20 3.5 3.0 2.5 2.0 1.5 SHADED AREA INDICATES STABLE OPERATION WITH NO NEED FOR ISOLATION RESISTOR. 1.0 0 10 100 1000 10,000 Figure 6. Isolation Resistance vs. Capacitive Loading to Minimize Peaking (<2dB) 1000 10,000 Figure 8. MAX4250-4254 Unity-Gain Bandwidth vs. Capacitive Load imize PC board trace lengths and resistor leads, and place external components close to the op amp’s pins. 25 MAX4250–MAX4254 (AV = +1) MAX4249/MAX4255–MAX4257 (AV = +10) RISO = 0 UCSP Package Consideration For general UCSP package information and PC layout considerations, please refer to the Maxim Application Note (Wafer-Level Ultra-Chip-Board-Scale-Package). SHADED AREA INDICATES STABLE OPERATION WITH NO NEED FOR ISOLATION RESISTOR. 15 100 NOTE: RISO CHOSEN FOR PEAKING <2dB. NOTE: USING AN ISOLATION RESISTOR REDUCES PEAKING. 20 10 CAPACITIVE LOAD (pF) CAPACITIVE LOADING (pF) 10 UCSP Reliability 5 0 10 100 1000 10,000 CAPACITIVE LOAD (pF) Figure 7. Peaking vs. Capacitive Load Reference Figure 6 to select a resistance value that will ensure a load capacitance that limits peaking to <2dB (25%). For example, if the capacitive load is 1000pF, the corresponding isolation resistor is 150Ω. Figure 7 shows that peaking occurs without the isolation resistor. Figure 8 shows the unity-gain bandwidth vs. capacitive load for the MAX4250–MAX4254. Power Supplies and Layout The MAX4249–MAX4257 operate from a single +2.4V to +5.5V power supply or from dual supplies of ±1.20V to ±2.75V. For single-supply operation, bypass the power supply with a 0.1µF ceramic capacitor placed close to the VDD pin. If operating from dual supplies, bypass each supply to ground. Good layout improves performance by decreasing the amount of stray capacitance and noise at the op amp’s inputs and output. To decrease stray capacitance, min12 VDD = 3V 0.5 0 PEAKING (dB) MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps The chip-scale package (UCSP) represents a unique packaging form factor that may not perform equally to a packaged product through traditional mechanical reliability tests. CSP reliability is integrally linked to the user’s assembly methods, circuit board material, and usage environment. The user should closely review these areas when considering use of a CSP package. Performance through Operating Life Test and Moisture Resistance remains uncompromised as it is primarily determined by the wafer-fabrication process. Mechanical stress performance is a greater consideration for a CSP package. CSPs are attached through direct solder contact to the user’s PC board, foregoing the inherent stress relief of a packaged product lead frame. Solder joint contact integrity must be considered. Table 1 shows the testing done to characterize the CSP reliability performance. In conclusion, the UCSP is capable of performing reliably through environmental stresses as indicated by the results in the table. Additional usage data and recommendations are detailed in the UCSP application note, which can be found on Maxim’s website at www.maxim-ic.com. ______________________________________________________________________________________ UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps +5V VDD 50k 2 MAX195 7 6 3 VIN MAX4256 4 8 (16-BIT ADC) AIN DOUT SHDN SCLK SERIAL INTERFACE CS 5k REF 4.096V VSS -5V SHDN Table 1. Reliability Test Data CONDITIONS DURATION NO. OF FAILURES PER SAMPLE SIZE -35°C to +85°C, -40°C to +100°C 150 cycles, 900 cycles 0/10, 0/200 TEST Temperature Cycle Operating Life TA = +70°C 240h 0/10 Moisture Resistance -20°C to +60°C, 90% RH 240h 0/10 Low-Temperature Storage -20°C 240h 0/10 Low-Temperature Operational -10°C 24h 0/10 Solderability 8h steam age — 0/15 ESD High-Temperature Operating Life ±2000V, Human Body Model — 0/5 168h 0/45 TJ = +150°C ______________________________________________________________________________________ 13 MAX4249–MAX4257 Typical Operating Circuit MAX4249–MAX4257 UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps Selector Guide PART GAIN BANDWIDTH (MHz) MINIMUM STABLE GAIN (V/V) NO. OF AMPLIFIERS PER PACKAGE SHUTDOWN MODE MAX4249 22 10 2 Yes MAX4250 3 1 1 — MAX4251 3 1 1 Yes MAX4252 3 1 2 — MAX4253 3 1 2 Yes MAX4254 3 1 4 — PIN-PACKAGE 10-pin µMAX, 14-pin SO 5-pin SOT23 8-pin µMAX/SO 8-pin µMAX/SO, 8-pin UCSP 10-pin µMAX, 14-pin SO, 10-pin UCSP 14-pin SO MAX4255 22 10 1 — MAX4256 22 10 1 Yes 8-pin µMAX/SO MAX4257 22 10 2 — 8-pin µMAX/SO Ordering Information (continued) TEMP. RANGE PIN/BUMPPACKAGE MAX4251ESA -40°C to +85°C 8 SO — MAX4251EUA -40°C to +85°C 8µMAX — MAX4252ESA -40°C to +85°C 8 SO — MAX4252EBA-T* -40°C to +85°C 8 UCSP AAO MAX4252EUA -40°C to +85°C 8 µMAX — MAX4253EUB -40°C to +85°C 10 µMAX — MAX4253EBB-T* -40°C to +85°C 10 UCSP AAK MAX4253ESD -40°C to +85°C 14 SO — MAX4254ESD -40°C to +85°C 14 SO — MAX4255EUK-T -40°C to +85°C 5 SOT23-5 MAX4256ESA -40°C to +85°C 8 SO — MAX4256EUA -40°C to +85°C 8 µMAX — MAX4257ESA -40°C to +85°C 8 SO — MAX4257EUA -40°C to +85°C 8 µMAX — PART TOP MARK 5-pin SOT23 Chip Information TRANSISTOR COUNTS: MAX4250/MAX4251/MAX4255/MAX4256: 170 MAX4249/MAX4252/MAX4253/MAX4257: 340 MAX4254: 680 ACCJ *UCSP reliability is integrally linked to the user’s assembly methods, circuit board material, and environment. Refer to the UCSP Reliability Notice in the UCSP Reliability section of this data sheet for more information. 14 ______________________________________________________________________________________ UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps TOP VIEW OUT 1 5 N.C. 1 VDD IN- 2 MAX4250 MAX4255 VSS 2 IN+ 3 IN+ 4 MAX4251 MAX4256 3 VSS 4 IN- INAINA+ 10 VDD 2 3 MAX4249 MAX4253 7 VDD INA- 2 6 OUT INA+ 5 N.C. OUTA 1 3 9 OUTB INA- 2 8 INB- INA+ 3 VSS 4 7 INB+ SHDNA 5 6 SHDNB N.C. 5 MAX4249 MAX4253 VSS 4 VDD 7 OUTB 6 INB- 5 INB+ 14 OUTD OUTA 1 13 OUTB INA- 2 13 IND- 12 INB- INA+ 3 12 IND+ 11 INB+ VDD 4 10 N.C. INB+ 5 SHDNA 6 9 SHDNB N.C. 7 8 N.C. SO MAX4252 MAX4257 8 µMAX/SO 14 VDD OUTA 1 VSS 4 µMAX SHDN µMAX/SO SOT23 OUTA 1 8 MAX4254 11 VSS 10 INC+ INB- 6 9 INC- OUTB 7 8 OUTC SO ______________________________________________________________________________________ 15 MAX4249–MAX4257 Pin Configurations (continued) UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps 8LUMAXD.EPS SOT5L.EPS MAX4249–MAX4257 Package Information 16 ______________________________________________________________________________________ UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps 10LUMAX.EPS 9LUCSP, 3x3.EPS ______________________________________________________________________________________ 17 MAX4249–MAX4257 Package Information (continued) UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps SOICN.EPS MAX4249–MAX4257 Package Information (continued) 18 ______________________________________________________________________________________ UCSP, Single-Supply, Low-Noise, Low-Distortion, Rail-to-Rail Op Amps 12L, USPC.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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 19 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX4249–MAX4257 Package Information (continued)