ADVANCED LINEAR DEVICES, INC. ALD2701A/ALD2701B ALD2701 DUAL MICROPOWER RAIL-TO-RAIL CMOS OPERATIONAL AMPLIFIER GENERAL DESCRIPTION FEATURES The ALD2701 is a dual monolithic CMOS micropower high slew rate operational amplifier intended for a broad range of analog applications using ±1V to ±6V dual power supply systems, as well as +2V to +12V battery operated systems. All device characteristics are specified for +5V single supply or ±2.5V dual supply systems. Supply current is 500µA maximum at 5V supply voltage. It is manufactured with Advanced Linear Devices' enhanced ACMOS silicon gate CMOS process. • All parameters specified for +5V single supply or ±2.5V dual supply systems • Rail to rail input and output voltage ranges • Unity gain stable • Extremely low input bias currents -- 1.0pA • High source impedance applications • Dual power supply ±1.0V to ±6.0V • Single power supply +2V to +12V • High voltage gain • Output short circuit protected • Unity gain bandwidth of 0.7MHz • Slew rate of 0.7V/µs • Low power dissipation • Symmetrical output drive The ALD2701 is designed to offer a trade-off of performance parameters providing a wide range of desired specifications. It offers the popular industry standard pin configuration of µA747 and ICL7621 types. The ALD2701 has been developed specifically for the +5V single supply or ±1V to ±6V dual supply user. Several important characteristics of the device make application easier to implement at those voltages. First, each operational amplifier can operate with rail-to-rail input and output voltages. This means the signal input voltage and output voltage can be equal to the positive and negative supply voltages. This feature allows numerous analog serial stages and flexibility in input signal bias levels. Secondly, each device was designed to accommodate mixed applications where digital and analog circuits may operate off the same power supply or battery. Thirdly, the output stage can typically drive up to 50pF capacitive and 10KΩ resistive loads. These features, combined with extremely low input currents, high open loop voltage gain of 100V/mV, useful bandwidth of 700KHz, a slew rate of 0.7V/µs, low power dissipation of 0.5mW, low offset voltage and temperature drift, make the ALD2701 a versatile, micropower dual operational amplifier. The ALD2701, designed and fabricated with silicon gate CMOS technology, offers 1pA typical input bias current. On chip offset voltage trimming allows the device to be used without nulling in most applications. Due to low voltage and low power operation, reliability and operating characteristics, such as input bias currents and warm up time, are greatly improved. APPLICATIONS • • • • • • • • • • • • Voltage follower/buffer/amplifier Charge integrator Photodiode amplifier Data acquisition systems High performance portable instruments Signal conditioning circuits Sensor and transducer amplifiers Low leakage amplifiers Active filters Sample/Hold amplifier Picoammeter Current to voltage converter PIN CONFIGURATION ORDERING INFORMATION Operating Temperature Range -55°C to +125°C 0°C to +70°C 0°C to +70°C 8-Pin CERDIP Package 8-Pin Small Outline Package (SOIC) 8-Pin Plastic Dip Package ALD 2701A DA ALD 2701B DA ALD 2701 DA ALD 2701A SA ALD 2701B SA ALD 2701 SA ALD 2701A PA ALD 2701B PA ALD 2701 PA OUT A 1 8 V+ -IN A 2 7 OUT B +IN A 3 6 -IN B V- 4 5 +IN B TOP VIEW DA, PA, SA PACKAGE * Contact factory for industrial temperature range © 1998 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, California 94089 -1706 Tel: (408) 747-1155 Fax: (408) 747-1286 http://www.aldinc.com ABSOLUTE MAXIMUM RATINGS Supply voltage, V+ Differential input voltage range Power dissipation Operating temperature range PA,SA package DA package Storage temperature range Lead temperature, 10 seconds 13.2V -0.3V to V+ +0.3V 600 mW 0°C to +70°C -55°C to +125°C -65°C to +150°C +260°C OPERATING ELECTRICAL CHARACTERISTICS TA = 25 °C VS = ±2.5V unless otherwise specified Min 2701A Typ Symbol Supply Voltage VS V+ Input Offset Voltage VOS Input Offset Current IOS 1.0 25 240 1.0 25 240 Input Bias Current IB 1.0 30 300 1.0 30 300 Input Voltage Range VIR Input Resistance RIN Input Offset Voltage Drift TCVOS Power Supply Rejection Ratio PSRR 65 65 80 80 65 65 80 80 60 60 Common Mode Rejection Ratio CMRR 65 65 83 83 65 65 83 83 Large Signal Voltage Gain AV 15 100 300 15 100 300 ±1.0 2.0 Max Min ±6.0 12.0 ±1.0 2.0 2701B Typ Max Parameter 5.3 2.8 ALD2701A/ALD2701B ALD2701 -0.3 -2.8 5.3 2.8 10 -2.48 2.48 -2.40 2.40 PD 10.0 11.0 mV mV RS ≤ 100KΩ 0°C ≤ TA ≤ +70°C 1.0 30 450 pA pA TA = 25°C 0°C ≤ TA ≤ +70°C 1.0 50 600 pA pA TA = 25°C 0°C ≤ TA ≤ +70°C 5.3 2.8 V V V+ = +5 VS = ±2.5V 5.0 5.8 -0.3 -2.8 7 VO low VO high Power Dissipation Dual Supply Single Supply 5 0.01 IS V V 5 0.001 4.999 Supply Current ±6.0 12.0 1012 4.99 ISC Test Conditions 1012 VO low VO high Output Short Circuit Current Unit 1012 10 Output Voltage Range 2701 Typ ±6.0 ±1.0 12.0 2.0 2.0 2.8 -0.3 -2.8 Min 240 µV/°C RS ≤ 100KΩ 80 80 dB dB R S ≤ 100KΩ 0°C ≤ TA ≤ +70°C 60 60 83 83 dB dB RS ≤ 100KΩ 0°C ≤ TA ≤ +70°C 10 80 300 V/mV V/mV V/mV RL = 100KΩ RL ≥ 1MΩ RL = 100KΩ 0°C ≤ TA ≤ +70°C 7 0.01 V V R L= 1MΩ V + = +5V 0°C ≤ TA ≤ +70°C -2.48 -2.40 2.48 2.40 -2.40 V V R L = 100KΩ 0°C ≤ TA ≤ +70°C 1 500 2.5 Ω 0.001 0.01 0.001 4.99 4.999 4.99 4.999 2.40 1 Max 240 -2.48 2.48 1 500 2.5 Advanced Linear Devices 240 mA 500 2.5 µA mW VIN = 0V No Load Both amplifiers VS = ±2.5V 2 OPERATING ELECTRICAL CHARACTERISTICS (cont'd) T A = 25°C VS = ±2.5V unless otherwise specified Parameter Symbol Input Capacitance CIN Bandwidth BW Slew Rate SR Rise time tr Min 2701A Typ Max Min 1 400 Overshoot Factor 2701B Typ Max Min 2701 Typ Max Unit Test Conditions 1 1 700 700 KHz 0.7 0.7 0.7 V/µs AV = +1 RL = 100KΩ 0.2 0.2 0.2 µs RL = 100KΩ 20 20 20 % RL = 100KΩ CL = 50pF 700 400 pF Settling Time ts 10.0 10.0 10.0 µs 0.1% AV = -1 CL = 50pF RL = 100KΩ Channel Separation CS 120 120 120 dB AV = 100 TA = 25 °C VS = ±5.0V unless otherwise specified Min 2701A Typ PSRR 83 83 83 dB RS ≤ 100KΩ Common Mode Rejection Ratio CMRR 83 83 83 dB RS ≤ 100KΩ Large Signal Voltage Gain AV 250 250 250 V/mV RL = 100KΩ Output Voltage Range VO low VO high V V RL = 100KΩ Bandwidth BW 1.0 1.0 1.0 MHz Slew Rate SR 1.0 1.0 1.0 V/µs -4.90 4.90 -4.98 4.98 Max -4.90 Min -4.98 4.90 4.98 Max -4.90 Unit Test Conditions Power Supply Rejection Ratio -4.98 4.98 Min 2701 Typ Symbol 4.90 Max 2701B Typ Parameter AV = +1 CL = 50pF VS = ± 2.5V -55°C ≤ TA ≤ +125°C unless otherwise specified 2701 DA Typ Max Unit 6.0 15.0 mV 8.0 8.0 8.0 nA 10.0 10.0 10.0 nA VOS 3.0 Input Offset Current IOS Input Bias Current IB Power Supply Rejection Ratio PSRR 60 75 60 75 60 75 dB RS ≤ 100KΩ Common Mode Rejection Ratio CMRR 60 83 60 83 60 83 dB RS ≤ 100KΩ Large Signal Voltage Gain AV 10 50 10 50 7 50 V/mV RL ≤ 100KΩ Output Voltage Range VO low VO high 2.35 -2.47 2.45 2.35 -2.47 2.45 V V R L ≤ 100KΩ -2.47 2.45 -2.40 Min Test Conditions Input Offset Voltage 2.35 Min 2701B DA Typ Max Symbol ALD2701A/ALD2701B ALD2701 Min 2701A DA Typ Max Parameter -2.40 Advanced Linear Devices -2.40 RS ≤ 100KΩ 3 Design & Operating Notes: 1. The ALD2701 CMOS operational amplifier uses a 3 gain stage architecture and an improved frequency compensation scheme to achieve large voltage gain, high output driving capability, and better frequency stability. In a conventional CMOS operational amplifier design, compensation is achieved with a pole splitting capacitor together with a nulling resistor. This method is, however, very bias dependent and thus cannot accommodate the large range of supply voltage operation as is required from a stand alone CMOS operational amplifier. The ALD2701 is internally compensated for unity gain stability using a novel scheme that does not use a nulling resistor. This scheme produces a clean single pole roll off in the gain characteristics while providing for more than 70 degrees of phase margin at the unity gain frequency. 2. The ALD2701 has complementary p-channel and n-channel input differential stages connected in parallel to accomplish rail to rail input common mode voltage range. This means that with the ranges of common mode input voltage close to the power supplies, one of the two differential stages is switched off internally. To maintain compatibility with other operational amplifiers, this switching point has been selected to be about 1.5V below the positive supply voltage. Since offset voltage trimming on the ALD2701 is made when the input voltage is symmetrical to the supply voltages, this internal switching does not affect a large variety of applications such as an inverting amplifier or non-inverting amplifier with a gain larger than 2.5 (5V operation), where the common mode voltage does not make excursions above this switching point. The user should however, be aware that this switching does take place if the operational amplifier is connected as a unity gain buffer, and should make provision in his design to allow for input offset voltage variations. 3. The input bias and offset currents are essentially input protection diode reverse bias leakage currents, and are typically less than 1pA at room temperature. This low input bias current assures that the analog signal from the source will not be distorted by input bias currents. Normally, this extremely high input impedance of greater than 1012Ω would not be a problem as the source impedance would limit the node impedance. However, for applications where source impedance is very high, it may be necessary to limit noise and hum pickup through proper shielding. 4. The output stage consists of class AB complementary output drivers, capable of driving a low resistance load. The output voltage swing is limited by the drain to source on-resistance of the output transistors as determined by the bias circuitry, and the value of the load resistor. When connected in the voltage follower configuration, the oscillation resistant feature, combined with the rail to rail input and output feature, makes an effective analog signal buffer for medium to high source impedance sensors, transducers, and other circuit networks. 5. The ALD2701 operational amplifier has been designed to provide full static discharge protection. Internally, the design has been carefully implemented to minimize latch up. However, care must be exercised when handling the device to avoid strong static fields that may degrade a diode junction, causing increased input leakage currents. In using the operational amplifier, the user is advised to power up the circuit before, or simultaneously with, any input voltages applied and to limit input voltages not to exceed 0.3V of the power supply voltage levels. 6. The ALD2701, with its micropower operation, offers numerous benefits in reduced power supply requirements, less noise coupling and current spikes, less thermally induced drift, better overall reliability due to lower self heating, and lower input bias current. It requires practically no warm up time as the chip junction heats up to only 0.2°C above ambient temperature under most operating conditions. TYPICAL PERFORMANCE CHARACTERISTICS ±7 +25°C INPUTS GROUNDED OUTPUT UNLOADED ±800 COMMON MODE INPUT VOLTAGE RANGE AS A FUNCTION OF SUPPLY VOLTAGE ±6 -25°C COMMON MODE INPUT VOLTAGE RANGE (V) SUPPLY CURRENT (µA) SUPPLY CURRENT AS A FUNCTION OF SUPPLY VOLTAGE TA = -55°C ±600 ±400 +70°C +125°C ±200 0 ±5 ±4 ±3 ±2 ±1 0 0 ±1 ±2 ±3 ±4 ±5 ±6 ±2 ±3 ±4 ±5 ±6 ±7 SUPPLY VOLTAGE (V) OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF LOAD RESISTANCE INPUT BIAS CURRENT AS A FUNCTION OF AMBIENT TEMPERATURE 10 VS = ±2.5V TA = 25°C INPUT BIAS CURRENT (pA) 10000 100 1 10K ±1 0 SUPPLY VOLTAGE (V) 1000 OPEN LOOP VOLTAGE GAIN (V/mV) TA = 25°C VS = ±2.5V 1000 100 10 1.0 0.1 100K 1M 10M -50 LOAD RESISTANCE (Ω) ALD2701A/ALD2701B ALD2701 -25 0 25 50 75 100 125 AMBIENT TEMPERATURE (°C) Advanced Linear Devices 4 TYPICAL PERFORMANCE CHARACTERISTICS OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF SUPPLY VOLTAGE AND TEMPERATURE OUTPUT VOLTAGE SWING (V) OPEN LOOP VOLTAGE GAIN (V/mV) 1000 OUTPUT VOLTAGE SWING AS A FUNCTION OF SUPPLY VOLTAGE 100 10 -55°C ≤ TA ≤ +125°C RL = 100KΩ ±6 +25°C ≤ TA ≤ +125°C RL = 100KΩ ±5 ±4 ±3 ±2 ±1 1 ±2 0 ±4 ±6 ±8 0 ±1 ±2 SUPPLY VOLTAGE (V) ±4 ±5 ±6 ±7 OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF FREQUENCY 120 +5 +4 OPEN LOOP VOLTAGE GAIN (dB) VS = ±2.5V +3 +2 +1 0 -1 -2 -3 -4 VS = ±2.5V TA = 25°C 100 80 60 0 40 45 20 90 0 135 180 -20 -5 -50 -25 0 +25 +50 +75 +100 +125 1 10 AMBIENT TEMPERATURE (°C) INPUT OFFSET VOLTAGE AS A FUNCTION OF COMMON MODE INPUT VOLTAGE 100 1K 10K 100K FREQUENCY (Hz) 1M PHASE SHIFT IN DEGREES INPUT OFFSET VOLTAGE (mV) INPUT OFFSET VOLTAGE AS A FUNCTION OF AMBIENT TEMPERATURE REPRESENTATIVE UNITS INPUT OFFSET VOLTAGE (mV) ±3 SUPPLY VOLTAGE (V) 10M LARGE - SIGNAL TRANSIENT RESPONSE 15 VS = ±2.5V TA = 25°C 10 2V/div VS = ±1.0V TA = 25°C RL = 100KΩ CL = 50pF 500mV/div 5µs/div 5 0 -5 -10 -15 -2 -1 0 +1 +2 +3 COMMON MODE INPUT VOLTAGE (V) LARGE - SIGNAL TRANSIENT RESPONSE 5V/div VS = ±2.5V TA = 25°C RL = 100KΩ CL = 50pF 2V/div 5µs/div ALD2701A/ALD2701B ALD2701 SMALL - SIGNAL TRANSIENT RESPONSE Advanced Linear Devices 100mV/div VS = ±2.5V TA = 25°C RL = 100KΩ CL = 50pF 20mV/div 2µs/div 5 TYPICAL APPLICATIONS RAIL-TO-RAIL VOLTAGE FOLLOWER/BUFFER RAIL-TO-RAIL WAVEFORM INPUT 5V ~ 1012Ω ZIN = +5V 0V 0.1µF - +5V OUTPUT 0V OUTPUT + VIN 1/2 ALD2701 0≤ VIN ≤ 5V Performance waveforms. Upper trace is the output of a Wien Bridge Oscillator. Lower trace is the output of Rail-to-Rail voltage follower. * See Rail to Rail Waveform RAIL-TO-RAIL WINDOW COMPARATOR HIGH INPUT IMPEDANCE RAIL-TO-RAIL PRECISION DC SUMMING AMPLIFIER +5V 8 V+ = +2.5V V1 V2 VREF (HIGH) 3 100K 1/2 ALD2701 + 1 1/4 74 C00 10M + 10M 2 0.1µF 1/2 ALD2701 VOUT 10M - 10M VOUT VIN 5 0.1µF + 7 V- ≤ VIN ≤ V+ V3 V4 V- ≤ VOUT ≤ V+ V- = - 2.5V 10M VOUT = V1 + V2 - V3 - V4 VREF (LOW) 6 - 100K 4 1/2 ALD2701 10M RIN = 10MΩ Accuracy limited by resistor tolerances and input offset voltage VOUT (LOW) FOR VREF (LOW) < VIN < VREF(HIGH) PHOTO DETECTOR CURRENT TO VOLTAGE CONVERTER WIEN BRIDGE OSCILLATOR (RAIL-TO-RAIL) SINE WAVE GENERATOR - RF = 5M +2.5V + 10K -2.5V C = .01µF I VOUT 1/2 ALD2701 .01µF 10K -2.5V 1/2 ALD2701 ~ 1.6KHZ 1 = 2πRC *See Rail to Rail Waveform VOUT = 1 X RF RL = 100K + 10K R = 10K ~ f= +2.5V - PHOTODIODE LOW VOLTAGE INSTRUMENTATION AMPLIFIER V+ 0.1µF 1M + 100K - 500K 100K V- 1/2 ALD2701 f max = 20KHz -40mV ≤ VIN ≤ 40mV V+ V+ 0.1µF 0.1µF + 50K V+ 1M 0.1µF 100K 1M 100K VOUT V- 0.1µF ALD1701 V- 1M + V- 0.1µF 1/2 ALD2701 ALD2701A/ALD2701B ALD2701 GAIN = 25 V- ≤ VOUT ≤ V+ All resistors are 1% V+ = +1.0V V- = -1.0V Short Circuit Input Current 1µA Advanced Linear Devices 6