19-2103; Rev 1; 10/06 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps The LMX321/LMX358/LMX324 are single/dual/quad, low-cost, low-voltage, pin-to-pin compatible upgrades to the LMV321/LMV358/LMV324 family of general purpose op amps. These devices offer rail-to-rail outputs and an input common-mode range that extends below ground. These op amps draw only 105µA of quiescent current per amplifier, operate from a single +2.3V to +7V supply, and drive 2kΩ resistive loads to within 40mV of either rail. The LMX321/LMX358/LMX324 are unity-gain stable with a 1.3MHz gain-bandwidth product capable of driving capacitive loads up to 400pF. The combination of low voltage, low cost, and small package size makes these amplifiers ideal for portable/battery-powered equipment. The LMX321 single op amp is available in ultra-small 5pin SC70 and space-saving 5-pin SOT23 packages. The LMX358 dual op amp is available in the tiny 8-pin SOT23 or the 8-pin µMAX® package. The LMX324 quad op amp is available in 14-pin TSSOP and SO packages. Features ♦ Upgrade to LMV321/LMV358/LMV324 Family ♦ Single +2.3V to +7V Supply Voltage Range ♦ Available in Space-Saving Packages 5-Pin SC70 (LMX321) 8-Pin SOT23 (LMX358) 14-Pin TSSOP (LMX324) ♦ 1.3MHz Gain-Bandwidth Product ♦ 105µA Quiescent Current per Amplifier (VCC = +2.7V) ♦ No Phase Reversal for Overdriven Inputs ♦ No Crossover Distortion ♦ Rail-to-Rail Output Swing ♦ Input Common-Mode Voltage Range: VEE - 0.2V to VCC - 0.8V ♦ Drives 2kΩ Resistive Loads Ordering Information Applications PINPACKAGE PKG CODE PART TEMP RANGE Laptops LMX321AXK-T -40°C to +125°C 5 SC70-5 X5-1 Low-Power, Low-Voltage Applications LMX321AUK-T -40°C to +125°C 5 SOT23-5 U5-1 Portable/Battery-Powered Equipment LMX358AKA-T -40°C to +125°C 8 SOT23-8 K8-2 LMX358ASA -40°C to +125°C 8 SO S8-2 LMX358AUA-T -40°C to +125°C 8 µMAX-8 U8-1 LMX324ASD -40°C to +125°C 14 SO S14-4 LMX324AUD -40°C to +125°C 14 TSSOP U14-1 Cellular Phones Cordless Phones Active Filters Selector Guide appears at end of data sheet. Pin Configurations TOP VIEW IN+ 1 LMX321 5 VCC VEE 2 4 OUT IN- 3 SC70-5/SOT23-5 8 VCC OUT1 1 14 OUT4 IN1- 2 7 OUT2 IN1- 2 13 IN4- IN1+ 3 6 IN2- IN1+ 3 12 IN4+ VEE 4 5 IN2+ VCC 4 OUT1 1 LMX358 SOT23-8/SO/µMAX LMX324 11 VEE IN2+ 5 10 IN3+ IN2- 6 9 IN3- OUT2 7 8 OUT3 TSSOP/SO ________________________________________________________________ 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 LMX321/LMX358/LMX324 General Description LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps ABSOLUTE MAXIMUM RATINGS Supply Voltage (VCC to VEE) ....................................-0.3V to +8V Differential Input Voltage (VIN+ - VIN-) ........................VEE to VCC OUT_ to VEE ...............................................-0.3V to (VCC + 0.3V) Output Short-Circuit Duration OUT_ Shorted to VCC or VEE ..................................Continuous Continuous Power Dissipation (TA = +70°C) 5-Pin SC70-5 (derate 3.1mW/°C above +70°C)...........247mW 5-Pin SOT23-5 (derate 7.1mW/°C above +70°C) ........571mW 8-Pin SOT23-8 (derate 7.52mW/°C above +70°C) ......602mW 8-Pin SO (derate 5.9mW/°C above +70°C)..................471mW 8-Pin µMAX (derate 4.5mW/°C above +70°C) .............362mW 14-Pin TSSOP (derate 9.1mW/°C above +70°C) .........727mW 14-Pin SO (derate 8.3mW/°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 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 (VCC = +2.7V, VEE = 0V, VOUT = VCC/2, VCM = 1V, RL > 1MΩ, TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS VOS 1 6 mV TCVOS 6 IB 18 50 nA IOS 1 8 nA DC CHARACTERISTICS Input Offset Voltage Input Offset Voltage Average Drift Input Bias Current Input Offset Current Common-Mode Rejection Ratio CMRR -0.2V < VCM < 1.8V Power-Supply Rejection Ratio PSRR 2.3V < VCC < 7V, VOUT = 1V -0.2 +1.9 AVOL RL = 2kΩ to VEE, 0.3V < VOUT < 2.4V LMX321 (single) Supply Current ICC dB Typ Large-Signal Voltage Gain RL = 2kΩ to 1.35V 96 +1.8 For CMRR > 72dB RL = 10kΩ to 1.35V 82 dB -0.2 VCM VOUT 92 Limit Input Common-Mode Voltage Range Output-Voltage Swing 72 µV/oC 20 120 V/mV VCC - VOH 12 50 VOL 10 40 VCC - VOH 40 110 VOL V 25 60 105 150 LMX358 (dual) 210 300 LMX324 (quad) 420 600 mV µA AC CHARACTERISTICS Slew Rate Gain-Bandwidth Product SR GBW 1V step Input CL = 200pF 1 V/µs 1.3 MHz degrees Phase Margin φM Gain Margin GM 24 dB Input Noise-Voltage Density en f = 1kHz 66 nV/√Hz Input Current-Noise Density in f = 1kHz 0.13 pA/√Hz 2 64 _______________________________________________________________________________________ Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps LMX321/LMX358/LMX324 ELECTRICAL CHARACTERISTICS (VCC = +2.7V, VEE = 0V, VOUT = VCC/2, VCM = 1V, RL > 1MΩ, TA = -40°C to +125°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS VOS 9 mV IB 70 nA IOS 15 nA DC CHARACTERISTICS Input Offset Voltage Input Bias Current Input Offset Current Common-Mode Rejection Ratio CMRR -0.1 < VCM < +1.7V Power-Supply Rejection Ratio PSRR 2.3V < VCC < 7V, VOUT = 1V 60 75 -0.1 +1.7 Typ -0.1 +1.8 VCM For CMRR > 60dB Large-Signal Voltage Gain AVOL RL = 2kΩ to VEE, 0.3V < VOUT < 2.4V RL = 10kΩ to 1.55V VOUT RL = 2kΩ to 1.35V Supply Current ICC dB Limit Input Common-Mode Voltage Range Output-Voltage Swing dB 10 V V/mV VCC - VOH 130 VOL 50 VCC - VOH 150 mV 70 VOL LMX321 (single) 180 LMX358 (dual) 360 LMX324 (quad) 720 µA ELECTRICAL CHARACTERISTICS (VCC = +5V, VEE = 0V, VOUT = VCC/2, VCM = 2V, RL > 1MΩ, TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS VOS 1 6 mV TCVOS 6 IB 18 50 nA IOS 1 8 nA DC CHARACTERISTICS Input Offset Voltage Input Offset Voltage Average Drift Input Bias Current Input Offset Current Force 100µA into IN+, IN- = GND measure VIN+ - VIN-, Figure 1 µV/oC 3.1 V 72 92 dB 82 96 dB Input Differential Clamp Voltage VCLAMP Common-Mode Rejection Ratio CMRR -0.2 < VCM < +4.1V Power-Supply Rejection Ratio PSRR 2.3V < VCC < 7V, VOUT = 1V, VCM = 1V Input Common-Mode Voltage Range VCM For CMRR > 72dB Limit -0.2 +4.1 Typ -0.2 +4.2 Large-Signal Voltage Gain AVOL RL = 2kΩ to VEE, 0.3V < VOUT < 4.7V 40 200 V V/mV _______________________________________________________________________________________ 3 LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps ELECTRICAL CHARACTERISTICS (continued) (VCC = +5V, VEE = 0V, VOUT = VCC/2, VCM = 2V, RL > 1MΩ, TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS RL = 10kΩ to 2.5V Output-Voltage Swing VOUT RL = 2kΩ to 2.5V Output Short-Circuit Current ISC Supply Current ICC TYP MAX VCC - VOH MIN 20 60 VOL 12 40 VCC - VOH 65 130 40 80 VOL Sourcing, VOUT = 0V 5 25 Sinking, VOUT = 5V 10 28 UNITS mV mA LMX321 (single) 120 170 LMX358 (dual) 240 340 LMX324 (quad) 480 680 µA AC CHARACTERISTICS Slew Rate Gain-Bandwidth Product SR 3V step input GBW 1 CL = 200pF V/µs 1.3 MHz Phase Margin φM 65 degrees Gain Margin GM 25 dB Input Noise-Voltage Density en f = 1kHz 65 nV/√Hz Input Noise-Current Density in f = 1kHz 0.13 pA/√Hz ELECTRICAL CHARACTERISTICS (VCC = +5V, VEE = 0V, VOUT = VCC/2, VCM = 2V, RL > 1MΩ, TA = -40°C to +125°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS VOS 9 mV IB 70 nA IOS 15 nA DC CHARACTERISTICS Input Offset Voltage Input Bias Current Input Offset Current Common-Mode Rejection Ratio CMRR -0.1 < VCM < +4.0V 63 dB Power-Supply Rejection Ratio PSRR 2.3V < VCC < 7V, VOUT = 1V, VCM = 1V 75 dB Input Common-Mode Voltage Range VCM For CMRR > 63dB Large-Signal Voltage Gain AVOL RL = 2kΩ to VEE, 0.3V < VOUT < 4.7V RL = 10kΩ to 2.5V Output-Voltage Swing VOUT RL = 2kΩ to 2.5V Supply Current ICC Limit -0.1 +4.0 Typ -0.1 +4.1 20 VCC - VOH V/mV 170 VOL 70 VCC - VOH 190 VOL 210 LMX358 (dual) 420 LMX324 (quad) 840 _______________________________________________________________________________________ mV 90 LMX321 (single) Note 1: Specifications are 100% tested at TA = +25°C (exceptions noted). All temperature limits are guaranteed by design. 4 V µA Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps TA = +85°C TA = +25°C 60 40 TA = -40°C 1 2 -16 -17 3 4 5 6 7 100 0 -100 -200 -300 VCC = +5V, VIN = VCC/2 -400 -5 -40 -25 -10 5 20 35 50 65 80 95 110 125 -4 -3 -2 -1 0 1 2 3 DIFFERENTIAL INPUT VOLTAGE (V) SOURCE CURRENT vs. OUTPUT VOLTAGE SOURCE CURRENT vs. OUTPUT VOLTAGE SINK CURRENT vs. OUTPUT VOLTAGE VCC = 5V 1 0.1 10 SINK CURRENT (mA) 10 100 LMX321 toc05 LMX321 toc04 100 1 0.1 0.01 0.1 1 10 VCC = 2.7V 10 1 0.01 0.1 1 0.01 0.001 10 0.01 0.1 1 10 OUTPUT VOLTAGE REFERENCED TO VCC (V) OUTPUT VOLTAGE REFERENCED TO VEE (V) SINK CURRENT vs. OUTPUT VOLTAGE OUTPUT VOLTAGE SWING vs. SUPPLY VOLTAGE OUTPUT VOLTAGE SWING vs. SUPPLY VOLTAGE 1 0.1 80 POSITIVE SWING (VCC - VOH) 70 60 50 40 30 0.01 0.1 1 10 RL = 10kΩ 30 POSITIVE SWING (VCC - VOH) 25 20 15 10 NEGATIVE SWING (VOL) NEGATIVE SWING (VOL) 20 OUTPUT VOLTAGE REFERENCED TO VEE (V) 35 LMX321 toc09 LMX321 toc08 RL = 2kΩ 90 OUTPUT VOLTAGE SWING (mV) 10 100 OUTPUT VOLTAGE SWING (mV) LMX321 toc07 OUTPUT VOLTAGE REFERENCED TO VCC (V) VCC = 5V 5 0.1 0.01 0.01 4 LMX321 toc06 TEMPERATURE (°C) VCC = 2.7V 0.01 0.001 200 SUPPLY VOLTAGE (V) SOURCE CURRENT (mA) SOURCE CURRENT (mA) -15 -20 0 SINK CURRENT (mA) -14 -19 0 100 -13 -18 20 100 -12 VCC = 5V 300 INPUT BIAS CURRENT (µA) 100 80 -11 INPUT BIAS CURRENT (nA) 120 400 LMX321 toc02 TA = +125°C 140 -10 LMX321 toc01 SUPPLY CURRENT PER AMPLIFIER (µA) 160 INPUT BIAS CURRENT vs. DIFFERENTIAL INPUT VOLTAGE INPUT BIAS CURRENT vs. TEMPERATURE LMX321 toc03 SUPPLY CURRENT PER AMPLIFIER vs. SUPPLY VOLTAGE 5 2 3 4 5 SUPPLY VOLTAGE (V) 6 7 2 3 4 5 6 7 SUPPLY VOLTAGE (V) _______________________________________________________________________________________ 5 LMX321/LMX358/LMX324 Typical Operating Characteristics (TA = +25°C, VEE = 0V, unless otherwise noted.) Typical Operating Characteristics (continued) (TA = +25°C, VEE = 0V, unless otherwise noted.) 2.5 2.0 1.5 1.0 LMX321 toc12 VCC = 5V, RL = 5kΩ -70 -90 -110 -130 -150 0 100 1k 10k 100k 1 10 100 1k 10k 100 100k 100k 1M 10M POWER-SUPPLY REJECTION RATIO vs. FREQUENCY INPUT OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE INPUT OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE PSRR- VCC = 1.35V, VEE = -1.35V 0.05 0.05 -0.05 -80 -0.10 -100 -0.15 -120 ∆VOS (mV) PSRR+ -60 1k 10k 100k 1M 0 -0.05 -0.10 -0.15 -0.20 -0.20 100 VCC = 2.5V, VEE = -2.5V 0.10 0 ∆VOS (mV) -40 0.15 LMX321 toc14 LMX321 toc13 0.10 -1.7 -1.2 -0.7 -0.2 0.3 -2.8 -2.3 -1.8 -1.3 -0.8 -0.3 0.2 0.7 1.2 1.7 2.2 0.8 FREQUENCY (Hz) COMMON-MODE VOLTAGE (V) COMMON-MODE VOLTAGE (V) INPUT OFFSET VOLTAGE vs. OUTPUT VOLTAGE INPUT OFFSET VOLTAGE vs. OUTPUT VOLTAGE GAIN AND PHASE vs. FREQUENCY and RESISTIVE LOAD 25 75 INPUT OFFSET VOLTAGE (mV) RL = 600Ω RL = 2kΩ 0 RL = 10kΩ -50 -75 RL = 600Ω RL = 2kΩ 0 RL = 10kΩ -25 -1 0 1 OUTPUT VOLTAGE (V) 2 3 60 20 40 RL = 600Ω 10 20 0 0 -50 -10 VCC = 2.5V, VEE = -2.5V CL = 0pF, RL TO VEE AVCL = 60dB, VOUT = 0V RL = 100kΩ -20 -20 -1.5 -1.0 -0.5 0 0.5 OUTPUT VOLTAGE (V) 1.0 1.5 100 80 RL = 100kΩ 30 25 100 -2 40 50 -75 -100 LMX321 toc18 50 GAIN (dB) 75 VCC = +1.35V, VEE = -1.35V LMX321 toc17 VCC = 2.5V, VEE = -2.5V 50 100 LMX321 toc16 100 100M LMX321 toc15 FREQUENCY (Hz) -20 -3 10k FREQUENCY (Hz) VCC = 2.7V TO 5V -25 1k FREQUENCY (Hz) -40 10k 100k 1M FREQUENCY (Hz) _______________________________________________________________________________________ 10M PHASE MARGIN (degrees) 10 0 PSRR (dB) 3.0 -50 0.5 1 6 VCC = 2.7V TO 5V, VCM = VCC/2 3.5 CROSSTALK REJECTION (dB) 4.0 LMX321 toc11 VCC = 2.7V TO 5V, VCM = VCC/2 LMX321 toc10 600 550 500 450 400 350 300 250 200 150 100 50 0 CROSSTALK REJECTION vs. FREQUENCY INPUT CURRENT NOISE vs. FREQUENCY INPUT CURRENT NOISE (pA/√Hz) INPUT VOLTAGE NOISE (nV/√Hz) INPUT VOLTAGE NOISE vs. FREQUENCY INPUT OFFSET VOLTAGE (µV) LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps LMX321 toc19 50 LMX321 toc20 50 100 GAIN AND PHASE vs. FREQUENCY AND CAPACITIVE LOAD LMX321 toc21 50 100 RL = 600Ω 20 RL = 600Ω 0 0 VCC = 1.35V, VEE = -1.35V CL = 0, RL TO VEE AVCL = 60dB, VOUT = 0V RL = 100kΩ -10 100k 1M 20 FREQUENCY (Hz) GAIN AND PHASE vs. FREQUENCY AND TEMPERATURE 50 100 20 TA = +85°C TA = +85°C 10 40 TA = -25°C TA = +125°C 20 0 0 VCC = 2.5V, VEE = -2.5V RL = 2kΩ TO VEE AVCL = 60dB, VOUT = 0V -10 -20 10k 100k 1M PHASE (degrees) TA = +25°C LOAD CAPACITANCE (pF) GAIN (dB) 60 1500 10M RL = 10kΩ VIN = 1V STEP, AVCL = +1V/V 1.08 RISING EDGE 1.06 1.04 1.02 FALLING EDGE 1.00 STABLE 0 -40 1M 1.10 1000 -40 100k SLEW RATE vs. SUPPLY VOLTAGE 2000 10M -20 CL = 0 CAPACITIVE-LOAD STABILITY 2500 500 0 CL = 100pF VCC = 2.5V, VEE = -2.5V RL = 100kΩ TO VEE AVCL = 60dB, VOUT = 0V 10k 3000 -20 20 FREQUENCY (Hz) UNSTABLE TA = -40°C 30 CL = 1nF FREQUENCY (Hz) 3500 TA = +25°C 80 -20 10M 4000 TA = -40°C 40 1M 40 10 -10 -20 SLEW RATE (V/µs) LMX321 toc22 100k 20 0 -40 10k 10M 0.98 0.96 100 1k 10k 2.0 100k 2.5 3.0 3.5 4.0 4.5 5.0 FREQUENCY (Hz) LOAD RESISTANCE (Ω) SUPPLY VOLTAGE (V) NONINVERTING LARGE-SIGNAL RESPONSE NONINVERTING SMALL-SIGNAL RESPONSE TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY LMX321 toc25 LMX321 toc26 RL = 2kΩ VCC = 5V VIN 1V/div 5.5 10 RL = 2kΩ VCC = 5V VIN 100mV/div VCC = 2.7V, AV = +10, VOUT = 1VP-P 1 THD+N (%) VOUT 1V/div 60 CL = 1nF CL = 500pF 0 VCC = 2.5V, VEE = -2.5V RL = 600Ω TO VEE AVCL = 60dB, VOUT = 0V -20 -40 10k 10 0 -20 -20 40 CL = 1nF 30 LMX321 toc27 -10 20 80 CL = 500pF LMX321 toc24 10 60 CL = 500pF GAIN (dB) 40 CL = 0 PHASE (degrees) 20 40 80 30 GAIN (dB) 60 RL = 100kΩ PHASE (degrees) 30 GAIN (dB) 40 80 MAXLMX toc23 40 100 CL = 0 CL = 100pF VOUT 100mV/div VCC = 5V, AV = +10, VOUT = 2.5VP-P 0.1 0.01 VCC = 2.7V, AV = +1, VOUT = 1VP-P VCC = 5V, AV = +1, VOUT = 2.5VP-P 0.001 1µs/div 1µs/div 10 100 1k 10k 100k FREQUENCY (Hz) _______________________________________________________________________________________ 7 PHASE (degrees) GAIN AND PHASE vs. FREQUENCY AND CAPACITIVE LOAD GAIN AND PHASE vs. FREQUENCY and RESISTIVE LOAD LMX321/LMX358/LMX324 Typical Operating Characteristics (continued) (TA = +25°C, VEE = 0V, unless otherwise noted.) Typical Operating Characteristics (continued) (TA = +25°C, VEE = 0V, unless otherwise noted.) VCC = 5V 30 25 VCC = 2.7V 20 15 10 VCC = 5V 30 25 20 VCC = 2.7V 15 10 5 LMX321 toc30 35 1000 LMX321 toc29 35 40 SHORT-CIRCUIT CURRENT (mA) LMX321 toc28 40 OUTPUT IMPEDANCE vs. FREQUENCY SHORT-CIRCUIT CURRENT vs. TEMPERATURE (SOURCING) VCC = 2.7V TO 5V AVCL = +1V/V OUTPUT IMPEDANCE (Ω) SHORT-CIRCUIT CURRENT vs. TEMPERATURE (SINKING) SHORT-CIRCUIT CURRENT (mA) LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps 100 10 1 0.01 5 0 0.001 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) TEMPERATURE (°C) 100 1k 10k 100k 1M 10M 100M FREQUENCY (Hz) Pin Description PIN NAME 8 FUNCTION LMX321 LMX358 LMX324 1 — — IN+ Noninverting Amplifier Input 2 4 11 VEE Negative Supply. Connect to ground for single-supply operation. 3 — — IN- Inverting Amplifier Input 4 — — OUT Output 5 8 4 VCC Positive Supply — 1 1 OUT1 — 2 2 IN1- Inverting Input for Amplifier 1 — 3 3 IN1+ Noninverting Input for Amplifier 1 — 7 7 OUT2 Output for Amplifier 2 — 6 6 IN2- Inverting Input for Amplifier 2 — 5 5 IN2+ Noninverting Input for Amplifier 2 — — 8 OUT3 Output for Amplifier 3 — — 9 IN3- Inverting Input for Amplifier 3 — — 10 IN3+ Noninverting Input for Amplifier 3 — — 14 OUT4 Output for Amplifier 4 — — 13 IN4- Inverting Input for Amplifier 4 — — 12 IN4+ Noninverting Input for Amplifier 4 Output for Amplifier 1 _______________________________________________________________________________________ Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps LMX321/LMX358/LMX324 3.5kΩ RL CL LMX321 LMX358 LMX324 3.5kΩ Figure 3. Capacitive-Load-Driving Circuit Figure 1. Input Protection Circuit VIN 2V/div VCC = 5V, VEE = 0V, CL = 2.2nF, RL = 2kΩ 2.6V 2.5V VIN 100mV/div 2.4V VOUT 1V/div 2.6V VOUT 100mV/div 2.4V -2.5V 200µs/div 4µs/div VCC = 2.5V, VEE = -2.5V, AVCL = 2V/V Figure 2. Rail-to-Rail Output Swing Detailed Description Input Protection Circuit The LMX321/LMX358/LMX324’s inputs are protected from large differential input voltages by internal 3.5kΩ series resistors and back-to-back triple diode stacks across the inputs (Figure 1). For differential input voltages (much less than 1.8V), input resistance is typically 3MΩ. For differential input voltages greater than 1.8V, input resistance is around 7kΩ, and the input bias current can be approximated by the following equation: IBIAS = (VDIFF - 1.8V) / 7kΩ In the region where the differential input voltage approaches 1.8V, input resistance decreases exponentially from 3MΩ to 7kΩ as the diode block begins conducting. Inversely, the bias current increases with the same curve. Figure 4. Output With Excessive Capacitive Load Rail-to-Rail Output Stage The LMX321/LMX358/LMX324 drive 2kΩ loads and still typically swing within 40mV of the supply rails. Figure 2 shows the output voltage swing of the LMX321 configured with AVCL = +2V/V. Driving Capacitive Loads Driving a capacitive load can cause instability in many op amps, especially those with low quiescent current. The LMX321/LMX358/LMX324 are unity-gain stable for a range of capacitive loads to above 400pF. Figure 4 shows the response of the LMX321 with an excessive capacitive load. Adding a series resistor between the output and the load capacitor (Figure 5) improves the circuit’s response by isolating the load capacitance from the op amp’s output. _______________________________________________________________________________________ 9 LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps RISO VCC 2V/div CL LMX321 LMX358 LMX324 VOUT 1V/div Figure 5. Capacitive-Load-Driving Circuit With Isolation Resistor Applications Information 4µs/div Power-Up The LMX321/LMX358/LMX324 outputs typically settle within 10µs after power-up. Figure 6 shows the output voltage on power-up and power-down. Power Supplies and Layout The LMX321/LMX358/LMX324 operate from a single +2.3V to +7V power supply. Bypass the power supply with a 0.1µF capacitor to ground as close to VCC as possible. Selector Guide AMPLIFIERS PER PACKAGE TOP MARK LMX321AXK-T 1 ACP LMX321AUK-T 1 ADSQ LMX358AKA-T 2 AAIR LMX358ASA 2 — LMX358AUA-T 2 — LMX324ASD 4 — LMX324AUD 4 — PART 10 Figure 6. Power-Up/Power-Down Waveform Good layout techniques optimize performance by minimizing the amount of stray capacitance at the op amp’s inputs and outputs. Place external components close to the op amp to minimize trace lengths and stray capacitance. Chip Information LMX321 TRANSISTOR COUNT: 88 LMX358 TRANSISTOR COUNT: 175 LMX324 TRANSISTOR COUNT: 349 PROCESS: Bipolar ______________________________________________________________________________________ Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps SC70, 5L.EPS PACKAGE OUTLINE, 5L SC70 21-0076 E 1 1 ______________________________________________________________________________________ 11 LMX321/LMX358/LMX324 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) SOT-23 5L .EPS LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps 12 ______________________________________________________________________________________ Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps SOT23, 8L .EPS ______________________________________________________________________________________ 13 LMX321/LMX358/LMX324 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 4X S 8 8 INCHES DIM A A1 A2 b E Ø0.50±0.1 H c D e E H 0.6±0.1 L 1 1 α 0.6±0.1 S BOTTOM VIEW D MIN 0.002 0.030 MAX 0.043 0.006 0.037 0.014 0.010 0.007 0.005 0.120 0.116 0.0256 BSC 0.120 0.116 0.198 0.188 0.026 0.016 6° 0° 0.0207 BSC 8LUMAXD.EPS LMX321/LMX358/LMX324 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps MILLIMETERS MAX MIN 0.05 0.75 1.10 0.15 0.95 0.25 0.36 0.13 0.18 2.95 3.05 0.65 BSC 2.95 3.05 4.78 5.03 0.41 0.66 0° 6° 0.5250 BSC TOP VIEW A1 A2 A α c e FRONT VIEW b L SIDE VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, 8L uMAX/uSOP APPROVAL DOCUMENT CONTROL NO. 21-0036 14 ______________________________________________________________________________________ REV. J 1 1 Single/Dual/Quad, General-Purpose, Low-Voltage, Rail-to-Rail Output Op Amps TSSOP4.40mm.EPS PACKAGE OUTLINE, TSSOP 4.40mm BODY 21-0066 I 1 1 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 © 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc. LMX321/LMX358/LMX324 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.)