ADVANCED LINEAR DEVICES, INC. ALD1704A/ALD1704B ALD1704/ALD1704G RAIL-TO-RAIL CMOS OPERATIONAL AMPLIFIER GENERAL DESCRIPTION FEATURES The ALD1704 is a CMOS monolithic operational amplifier with MOSFET input that has rail-to-rail input and output voltage ranges. The input voltage range and output voltage range are very close to the positive and negative power supply voltages. Typically the input voltage can be beyond positive power supply voltage V+, or the negative power supply voltage V- by up to 300mV. The output voltage swings to within 60mV of either positive or negative power supply voltages at rated load. • • • • • • • This device is designed as an alternative to the popular JFET input operational amplifiers in applications where lower operating voltages, such as 9V battery or ±3.25V to ±6V power supplies are being used. It offers high slew rate of 5V/µs at low operating power of 30mW. Since the ALD1704 is designed and manufactured with Advanced Linear Devices' standard enhanced ACMOS silicon gate CMOS process, it also offers low unit cost and exceptional reliability. • • • • Rail-to-rail input and output voltage ranges 5.0V/µs slew rate Output settles to 2mV of supply rails High capacitive load capability -- up to 4000pF Symmetrical push-pull output drives No frequency compensation required -unity gain stable Extremely low input bias currents -- 1.0pA typical (20pAMax) Ideal for high source impedance applications High voltage gain -- typically 150V/mV Output short circuit protected Unity gain bandwidth of 2.1MHz APPLICATIONS The rail-to-rail input and output feature of the ALD1704 allows a lower operating supply voltage for a given signal voltage range and allows numerous analog serial stages to be implemented without losing operating voltage margin. The output stage is designed to drive up to 10mA into 400pF capacitive and 1.5KΩ resistive loads at unity gain and up to 4000 pF at a gain of 5. Short circuit protection to either ground or the power supply rails is at approximately 15mA clamp current. Due to complementary output stage design, the output can both source and sink 10mA into a load with symmetrical drive and is ideally suited for applications where push-pull voltage drive is desired. The offset voltage is trimmed on-chip to eliminate the need for external nulling in many applications. For precision applications, the output is designed to settle to 0.1% in 2µs. For large signal buffer applications, the operational amplifier can function as an ultra high input impedance voltage follower/buffer that allows input and output voltage swings from positive to negative supply voltages. This feature is intended to greatly simplify systems design and eliminate higher voltage power supplies in many applications. ORDERING INFORMATION -55°C to +125°C • • • • • • • • • • • • • • • Voltage amplifier Voltage follower/buffer Charge integrator Photodiode amplifier Data acquisition systems High performance portable instruments Signal conditioning circuits Low leakage amplifiers Active filters Sample/Hold amplifier Picoammeter Current to voltage converter Coaxial cable driver Capacitive sensor amplifier Piezoelectric transducer amplifier PIN CONFIGURATION Operating Temperature Range 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 ALD1704A DA ALD1704B DA ALD1704 DA ALD1704G DA ALD1704A SA ALD1704B SA ALD1704 SA ALD1704G SA ALD1704A PA ALD1704B PA ALD1704 PA ALD1704G PA N/C 1 8 N/C -IN 2 7 V+ +IN 3 6 OUT V- 4 5 N/C TOP VIEW DA, PA, SA PACKAGE * N/C Pin is internally connected. Do not connect externally. * 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 = ±5.0V unless otherwise specified Parameter Symbol Min 1704A Typ Max ±3.25 6.5 ±6.0 12.0 Min 1704B Typ Max ±3.25 6.5 ±6.0 12.0 Min 1704 Typ Max ±3.25 6.5 ±6.0 12.0 Min 1704G Typ Max ±3.25 6.5 Unit Test Conditions ±6.0 12.0 V V Dual Supply Single Supply 10.0 11.0 mV mV RS ≤ 100KΩ 0°C ≤ TA ≤ +70°C 1.0 25 240 pA pA TA = 25°C 0°C ≤ TA ≤ +70°C 20 300 1.0 30 300 pA pA TA = 25°C 0°C ≤ TA ≤ +70°C +5.3 ±5.0 V Ω Supply Voltage VS V+ Input Offset Voltage VOS Input Offset Current IOS 1.0 15 240 1.0 15 240 1.0 15 240 Input Bias Current IB 1.0 20 300 1.0 20 300 1.0 Input Voltage Range VIR Input Resistance RIN Input Offset Voltage Drift TCVOS Power Supply Rejection Ratio PSRR 70 80 65 80 65 80 60 Common Mode Rejection Ratio CMRR 70 83 65 83 65 83 Large Signal Voltage Gain AV 50 150 150 50 150 150 50 150 150 Output Voltage Range VO low VO high VO low VO high Output Short Circuit Current ISC 15 Supply Current IS 3.0 4.5 3.0 4.5 3.0 4.5 3.0 5.0 mA VIN = 0V No Load Power Dissipation PD 30 45 30 45 30 45 30 50 mW VS = ±5.0 No Load Input Capacitance CIN 1 1 1 1 Bandwidth BW 2.1 2.1 2.1 2.1 MHz Slew Rate SR 5.0 5.0 5.0 5.0 V/µs AV = +1 RL = 2.0KΩ Rise time tr 0.1 0.1 0.1 0.1 µs RL = 2.0KΩ 15 15 15 15 % RL = 2.0KΩ CL = 100pF 0.9 1.7 -5.3 +5.3 ALD1704A/ALD1704B ALD1704/ALD1704G -5.3 +5.3 4.5 5.3 -5.3 1012 1012 1012 1012 5 5 5 7 40 Overshoot Factor 2.0 2.8 40 -4.96 -4.90 4.95 -4.998 -4.99 4.99 4.998 4.90 40 -4.96 4.95 -4.998 4.99 4.998 -4.90 4.90 15 RS ≤ 100KΩ 80 dB R S ≤ 100KΩ 0°C ≤ TA ≤ +70°C 60 83 dB RS ≤ 100KΩ 0°C ≤ TA ≤ +70°C 32 150 150 V/ mV V/ mV V/ mV RL = 10KΩ No Load 0°C ≤ TA ≤ +70°C V R L = 10KΩ 0°C ≤ TA ≤ +70°C R L =1MΩ 0°C ≤ TA ≤ +70°C 20 -4.96 -4.90 4.95 -4.998 -4.99 4.99 4.998 4.90 -4.99 µV/°C 15 Advanced Linear Devices -4.96 -4.90 4.95 -4.998 -4.99 4.99 4.998 4.90 15 V mA pF 2 OPERATING ELECTRICAL CHARACTERISTICS (cont'd) T A = 25°C VS = ±5.0V unless otherwise specified Min 1704B Typ Max Min 1704 Typ Max Min 1704G Typ Max Symbol Maximum Load Capacitance CL 400 4000 400 4000 400 4000 400 4000 Input Noise Voltage en 26 26 26 Input Current Noise in 0.6 0.6 ts 5.0 2.0 5.0 2.0 Settling Time Min 1704A Typ Max Parameter Unit Test Conditions pF pF Gain = 1 Gain = 5 26 nV/√Hz f = 1KH Z 0.6 0.6 fA/√HZ f = 10HZ 5.0 2.0 5.0 2.0 µs µs 0.01% 0.1% AV = -1 RL = 5KΩ CL = 50pF VS = ±5.0V -55°C ≤ T A ≤ +125°C unless otherwise specified Parameter Symbol 1704A DA Min Typ Max 1704B DA Min Typ Max Min 1704DA Typ Max Unit Test Conditions RS ≤ 100KΩ Input Offset Voltage VOS 2.0 4.0 7.0 mV Input Offset Current IOS 8.0 8.0 8.0 nA Input Bias Current IB 10.0 10.0 10.0 nA Power Supply Rejection Ratio PSRR 60 75 60 75 60 75 dB R S ≤ 100KΩ Common Mode Rejection Ratio CMRR 60 83 60 83 60 83 dB RS ≤ 100KΩ Large Signal Voltage Gain AV 30 125 30 125 30 125 V/mV RL = 10KΩ Output Voltage Range VO low VO high 4.8 -4.9 4.9 4.8 -4.9 4.9 4.8 -4.9 4.9 V V RL = 10KΩ RL = 10KΩ ALD1704A/ALD1704B ALD1704/ALD1704G -4.8 -4.8 Advanced Linear Devices -4.8 3 Design & Operating Notes: 1. The ALD1704 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. The ALD1704 is internally compensated for unity gain stability using a novel scheme that 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. A unity gain buffer using the ALD1704 will typically drive 400pF of external load capacitance without stability problems. In the inverting unity gain configuration, it can drive up to 800pF of load capacitance. Compared to other CMOS operational amplifiers, the ALD1704 has shown itself to be more resistant to parasitic oscillations. 2. The ALD1704 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 above the negative supply voltage. Since offset voltage trimming on the ALD1704 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 (10V operation), where the common mode voltage does not make excursions below this switching point. 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. 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 symmetrical class AB complementary output drivers, capable of driving a low resistance load with up to 10mA source current and 10mA sink current. 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 the ALD1704 an effective analog signal buffer for medium to high source impedance sensors, transducers, and other circuit networks. 5. The ALD1704 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 to not exceed 0.3V of the power supply voltage levels. TYPICAL PERFORMANCE CHARACTERISTICS OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF SUPPLY VOLTAGE AND TEMPERATURE COMMON MODE INPUT VOLTAGE RANGE AS A FUNCTION OF SUPPLY VOLTAGE ±7 1000 } -55°C ±6 OPEN LOOP VOLTAGE GAIN (V/mV) COMMON MODE INPUT VOLTAGE RANGE (V) TA = 25°C ±5 ±4 ±3 ±2 } +125°C 10 RL= 10KΩ RL= 5KΩ 1 ±3 ±2 ±4 ±5 ±6 ±7 ±2 0 ±4 ±8 ±6 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) INPUT BIAS CURRENT AS A FUNCTION OF AMBIENT TEMPERATURE SUPPLY CURRENT AS A FUNCTION OF SUPPLY VOLTAGE 5 10000 VS = ±5.0V 1000 SUPPLY CURRENT (mA) INPUT BIAS CURRENT (pA) } +25°C 100 100 10 1.0 INPUTS GROUNDED OUTPUT UNLOADED 4 3 TA = -55°C 2 -25°C +25°C 1 +80°C +125°C 0 0.1 -50 -25 0 25 50 75 100 0 125 AMBIENT TEMPERATURE (°C) ALD1704A/ALD1704B ALD1704/ALD1704G ±1 ±2 ±3 ±4 ±5 ±6 SUPPLY VOLTAGE (V) Advanced Linear Devices 4 TYPICAL PERFORMANCE CHARACTERISTICS 120 ±25°C ≤ TA ≤ 125°C 100 OPEN LOOP VOLTAGE GAIN (dB) ±6 RL = 10KΩ RL = 10KΩ ±5 ±4 RL = 2KΩ ±3 ±2 VS = ±5.0V TA = 25°C 80 60 0 40 45 20 90 0 135 180 -20 0 ±1 ±2 ±3 ±4 ±5 ±6 ±7 1 10 100 10K 100K 1M 10M SUPPLY VOLTAGE (V) FREQUENCY (Hz) INPUT OFFSET VOLTAGE AS A FUNCTION OF AMBIENT TEMPERATURE REPRESENTATIVE UNITS INPUT OFFSET VOLTAGE AS A FUNCTION OF COMMON MODE INPUT VOLTAGE INPUT OFFSET VOLTAGE (mV) 15 +5 +4 VS = ±5.0V +3 +2 +1 0 -1 -2 -3 -4 VS = ±5.0V TA = 25°C 10 5 0 -5 -10 -15 -5 -50 -25 0 +25 +50 +75 -4 +100 +125 -2 +2 +4 +6 LARGE - SIGNAL TRANSIENT RESPONSE OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF LOAD RESISTANCE 1000 5V/div 100 0 COMMON MODE INPUT VOLTAGE (V) AMBIENT TEMPERATURE (°C) OPEN LOOP VOLTAGE GAIN (V/mV) 1K PHASE SHIFT IN DEGREES OUTPUT VOLTAGE SWING (V) ±7 INPUT OFFSET VOLTAGE (mV) OPEN LOOP VOLTAGE AS A FUNCTION OF FREQUENCY OUTPUT VOLTAGE SWING AS A FUNCTION OF SUPPLY VOLTAGE VS = ±5.0V TA = 25°C RL = 1KΩ CL = 50pF VS = ±5.0V TA = 25°C 10 5V/div 2µs/div 1 1K 10K 100K 1000K LOAD RESISTANCE (Ω) SMALL - SIGNAL TRANSIENT RESPONSE VOLTAGE NOISE DENSITY AS A FUNCTION OF FREQUENCY VOLTAGE NOISE DENSITY (nV/ √ Hz) 150 100mV/div 125 VS = ±5.0V TA = 25°C 100 VS = ± 5.0V TA = 25°C RL = 1.0KΩ CL = 50pF 75 50 25 50mV/div 1µs/div 0 10 100 1K 10K 100K 1000K FREQUENCY (Hz) ALD1704A/ALD1704B ALD1704/ALD1704G Advanced Linear Devices 5 TYPICAL APPLICATIONS RAIL-TO-RAIL VOLTAGE FOLLOWER/BUFFER RAIL-TO-RAIL VOLTAGE COMPARATOR +12V +10V = 1012Ω ZIN ~ 0.1µF VIN CL + VIN VOUT VOUT RL ≥ 1.5KΩ 400pF 0 ≤ VIN ≤ 10V 0.1µF - +12V + 50K 10M PHOTO DETECTOR CURRENT TO VOLTAGE CONVERTER LOW OFFSET SUMMING AMPLIFIER RF = 5M 10K 50K +5V 0.1µF INPUT 1 I - INPUT 2 10K VOUT GAIN = 5 + * Circuit Drives Large Load Capacitance ≤ 4000pF +5V - CL = 4000pF RL ≥ 1.5K + -5V -5V 0.1µF BANDPASS NETWORK WIEN BRIDGE OSCILLATOR (RAIL-TO -RAIL) SINE WAVE GENERATOR C2 R2 +5V - VOUT + C1 R1 VIN - .01µF R = 10K 10K VOUT Low Frequency Breakpoint ƒL = 10K 1 ~ ~ 1.6K Hz f= = 2πRC High Frequency Cutoff ƒH = LOW PASS FILTER (RFI FILTER) RF 5K VIN R1 C1 -5V 1 = 160Hz 2π R1 C1 R1 = 10K C1 = 100nF R2 = 10K C2 = 500pF 1 = 32KHz 2π R2C2 PRECISION CHARGE INTEGRATOR 100K 1000pF 5K R1 +5V 10K -5V + C = .01µF VOUT = I X RF PHOTODIODE +9V - 0.02µF VOUT +5V 1MΩ VIN - + VOUT + -5V 1 Cutoff frequency = = 3.2kHz π R1C1 Gain = 10 Frequency roll-off 20dB/decade ALD1704A/ALD1704B ALD1704/ALD1704G Advanced Linear Devices 6