19-2023; Rev 0; 1/02 1.0V Micropower, SOT23, Operational Amplifier Applications Single-Cell Systems Strain Gauges Portable Electronic Equipment Cellular Phones Battery-Powered Instrumentation Sensor Amplifiers Features ♦ Ultra-Low Voltage Operation: Guaranteed Specifications from 1.0V to 5.5V ♦ Input Common-Mode Range: 0 to (VCC - 0.2V) ♦ Ultra-Low Power Consumption: 9µA Supply Current (typ) ♦ Optimized for Operation from Single-Cell Battery-Powered Systems ♦ Compatible with 3.0V and 5.0V Single-Supply Systems ♦ Low Offset Voltage: 0.2mV ♦ Low Input Bias Current: 5nA ♦ High Open-Loop Voltage Gain: 90dB ♦ Rail-to-Rail Output Stage Drives 5kΩ Load ♦ No Output Phase Reversal for Overdriven Inputs ♦ Available in a Tiny 6-Pin SOT23 (3mm ✕ 3mm) Ordering Information Notebook Computers Portable Communication Devices Hearing Aids Using Zinc Air Battery PART TEMP RANGE MAX4289EUT-T -40°C to +85°C PINPACKAGE 6 SOT23-6 MAX4289ESA -40°C to +85°C 8 SO — Pin Configurations Typical Operating Characteristic POWER-SUPPLY REJECTION RATIO vs. SUPPLY VOLTAGE TOP MARK AARX TOP VIEW 90 TA = +85°C OUT 1 6 VCC N.C. 1 8 N.C. 7 VCC 3 6 OUT GND 4 5 N.C. PSRR (dB) 80 GND 2 MAX4289 IN- 2 IN+ TA = -40°C 70 MAX4289 5 N.C. IN+ 3 4 IN- TA = +25°C 60 SOT23-6 SO-8 50 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 SUPPLY VOLTAGE (V) 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 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX4289 General Description The MAX4289 micropower, operational amplifier is optimized for ultra-low supply voltage operation. The amplifier consumes only 9µA of quiescent supply current and is fully specified for operation from a single 1.0V to 5.5V power supply. This ultra-low voltage operation together with the low quiescent current consumption make the MAX4289 ideal for use in battery-powered systems operated from as little as a single alkaline cell. The MAX4289 also features a wide input common-mode range that includes the ground, and an output voltage swing that is virtually Rail-to-Rail®, allowing almost all of the power supply to be used for signal voltage. The low input offset voltage and low input bias current specifications along with the high open-loop gain make the MAX4289 well-suited to applications requiring a high degree of precision. The MAX4289 is available in a tiny 6-pin SOT23 package. All specifications are guaranteed over the extended temperature range of -40°C to +85°C. MAX4289 1.0V Micropower, SOT23, Operational Amplifier ABSOLUTE MAXIMUM RATINGS Power-Supply Voltage (VCC to GND).......................................6V Input Voltage (IN+ or IN-) ...........................(VCC + 0.3V) to -0.3V Input Current (IN+ or IN-)....................................................20mA Output Short-Circuit Duration to VCC or GND ............Continuous Continuous Power Dissipation (TA = +70°C) 6-Pin SOT23 (derate 8.7mW/°C above +70°C).............696mW 8-Pin SO (derate 5.88mW/°C above +70°C).................471mW Operating Temperature Range ...........................-40°C to +85°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 = 3V, VCM = 0, VOUT = VCC/2, RL tied to VCC/2, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL Supply Voltage Range VCC Quiescent Supply Current ICC Input Offset Voltage VOS CONDITIONS Inferred from the PSRR tests MIN MAX 1.0 5.5 TA = -40°C to +85°C 1.2 5.5 VCC = 1.0V, TA = +25°C 9 14 VCC = 3.0V 12 25 VCC = 5.5V 18 40 TA = +25°C ±0.2 ±2.0 ±6.0 TA = TMIN to TMAX UNITS V µA mV IB ±5 ±15 nA Input Offset Current IOS ±0.5 ±2.0 nA Differential Input Resistance RIN Input Bias Current Input Common-Mode Voltage Range VCM 50 Inferred from CMRR test CMRR 0 VCC - 0.2 VCC = 3.0V 0 VCC - 0.8 57 85 VCC = 3.0V, 0 ≤ VCM ≤ VCC - 0.8V 57 110 1.0V ≤ VCC ≤ 5.5V, TA = +25°C 54 75 1.2V ≤ VCC ≤ 5.5V, TA = -40°C to +85°C 58 75 PSRR Large-Signal Voltage Gain AVOL Output Voltage Swing High VOH Specified as |VCC - VOH| Output Voltage Swing Low VOL Specified as VOL RL = 100kΩ (50mV ≤ VOUT ≤ VCC - 50mV) RL = 5kΩ (100mV ≤ VOUT ≤ VCC - 100mV) RL = 100kΩ RL = 5kΩ RL = 100kΩ RL = 5kΩ V 57 VCC = 1.2V, 0 ≤ VCM ≤ VCC - 0.8V Power-Supply Rejection Ratio MΩ VCC = 1.2V VCC = 1.2V, 0 ≤ VCC - 0.2V Common-Mode Rejection Ratio 2 TYP TA = +25°C dB dB 110 80 dB 90 0.2 10 7 40 0.4 10 7 40 _______________________________________________________________________________________ mV mV 1.0V Micropower, SOT23, Operational Amplifier (VCC = 3V, VCM = 0, VOUT = VCC/2, RL tied to VCC/2, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL Output Short-Circuit Current Sourcing/sinking current IOUT Power-Up Time Input Capacitance CONDITIONS MIN TYP VCC = 1.0V 0.6 VCC = 3.0V 19 tPU 300 MAX UNITS mA µs CIN 3.0 pF GBW 17 kHz Phase Margin θM 80 degrees Gain Margin GM 10 dB Slew Rate SR 6 V/ms AVCL = +1V/V, no sustained oscillations 200 pF AVCL = +1V/V, no sustained oscillations 75 µs Gain-Bandwidth Product Capacitive-Load Stability Settling Time to 0.1% tS Note 1: All specifications are 100% production tested at TA = +25°C. Temperature specification limits are guaranteed by design. Typical Operating Characteristics (VCC = 3V, VCM = 0, RL to VCC/2, TA = +25°C, unless otherwise noted.) 10 VCC = 1V 8 6 4 0.4 0.2 0 -0.2 -0.4 -0.6 0 -0.8 -20 0 20 60 40 TEMPERATURE (°C) 80 100 MAX4289 toc03 0.6 2 -40 MAX4289 toc02 VCC = 3V 12 0.8 0.6 INPUT OFFSET VOLTAGE (mV) SUPPLY CURRENT (µA) 14 0.8 INPUT OFFSET VOLTAGE (mV) MAX4289 toc01 16 INPUT OFFSET VOLTAGE vs. TEMPERATURE INPUT OFFSET VOLTAGE vs. INPUT COMMON-MODE VOLTAGE SUPPLY CURRENT vs. TEMPERATURE 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 0 0.5 1.0 1.5 2.0 2.5 INPUT COMMON-MODE VOLTAGE (V) 3.0 -40 -20 0 20 60 40 TEMPERATURE (°C) 80 100 _______________________________________________________________________________________ 3 MAX4289 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (VCC = 3V, VCM = 0, RL to VCC/2, TA = +25°C, unless otherwise noted.) 8 7 6 RL CONNECTED TO GND 18 16 20 RL = 5kΩ 14 VOH (mV) INPUT BIAS CURRENT (nA) 9 20 MAX4289 toc05 30 MAX4289 toc04 10 10 12 10 8 6 0 4 5 RL = 100kΩ 2 4 0 20 40 60 80 100 0.5 1.0 1.5 2.0 2.5 -40 3.0 -20 0 20 40 60 80 100 250 300 TEMPERATURE (°C) INPUT COMMON-MODE VOLTAGE (V) TEMPERATURE (°C) OUTPUT SWING LOW vs. TEMPERATURE OPEN-LOOP GAIN vs. OUTPUT SWING LOW OPEN-LOOP GAIN vs. OUTPUT SWING HIGH RL CONNECTED TO VCC 18 0 130 16 RL = 100kΩ 110 130 MAX4289 toc08 -20 MAX4289 toc07 20 RL = 100kΩ 110 RL = 5kΩ GAIN (dB) 12 10 8 90 GAIN (dB) 14 VOL (mV) 0 -10 -40 MAX4289 toc09 INPUT BIAS CURRENT (nA) OUTPUT SWING HIGH vs. TEMPERATURE INPUT BIAS CURRENT vs. INPUT COMMON-MODE VOLTAGE MAX4289 toc06 INPUT BIAS CURENT vs. TEMPERATURE RL = 5kΩ 70 90 RL = 5kΩ 70 6 4 50 2 50 RL = 100kΩ 30 -40 -20 0 20 40 60 80 100 30 0 50 150 200 250 300 0 50 100 150 200 TEMPERATURE (°C) VOUT FROM GND (mV) VOUT FROM VCC (mV) OPEN-LOOP GAIN vs. TEMPERATURE OPEN-LOOP GAIN vs. TEMPERATURE GAIN AND PHASE vs. FREQUENCY (CL = 0) RL = 100kΩ 110 110 80 RL = 5kΩ 90 RL CONNECTED TO VCC 0 20 40 60 TEMPERATURE (°C) 80 100 80 20 60 40 PHASE -40 -20 0 20 20 -10 60 -20 100 30 0 70 -40 120 40 10 RL CONNECTED TO GND 60 140 GAIN 50 80 70 160 60 GAIN (dB) RL = 5kΩ 90 180 70 100 GAIN (dB) 100 RL = 100kΩ MAX4289 toc12 80 MAX4289 toc11 120 MAX4289 toc10 120 4 100 40 60 TEMPERATURE (°C) 80 100 -20 0.01 0 -20 0.1 1 FREQUENCY (kHz) _______________________________________________________________________________________ 10 100 PHASE (DEGREES) 0 GAIN (dB) MAX4289 1.0V Micropower, SOT23, Operational Amplifier 1.0V Micropower, SOT23, Operational Amplifier MINIMUM-OPERATING VOLTAGE vs. TEMPERATURE LARGE-SIGNAL TRANSIENT RESPONSE MAX4289 toc13 MAX4289 toc14 1.2 MAX4289 toc15 SMALL-SIGNAL TRANSIENT RESPONSE PSRR > 70dB IN 1V/div 1.1 VCC (V) IN 50mV/div OUT 50mV/div OUT 1V/div 1.0 0.9 0.8 10µs/div -40 200µs/div -20 0 20 40 60 80 100 TEMPERATURE (°C) VCC = 1V SINKING CURRENT 0.9 0.6 15 10 5 0.3 0 0 0.2 0.4 0.6 0.8 0 1.0 0.5 1.0 1.5 2.0 2.5 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) OUTPUT SOURCING CURRENT vs. OUTPUT VOLTAGE OUTPUT SOURCING CURRENT vs. OUTPUT VOLTAGE 25 MAX4289 toc18 1.0 VCC = 1V SOURCING CURRENT VCC = 3V SOURCING CURRENT 20 OUTPUT CURRENT (mA) 0.8 0.6 0.4 0.2 3.0 MAX4289 toc19 0 OUTPUT CURRENT (mA) VCC = 3V SINKING CURRENT 20 OUTPUT CURRENT (mA) 1.2 OUTPUT CURRENT (mA) 25 MAX4289 toc16 1.5 MAX4289 toc17 OUTPUT SINKING CURRENT vs. OUTPUT VOLTAGE OUTPUT SINKING CURRENT vs. OUTPUT VOLTAGE 15 10 5 0 0 0 0.2 0.4 0.6 OUTPUT VOLTAGE (V) 0.8 1.0 0 0.5 1.0 1.5 2.0 2.5 3.0 OUTPUT VOLTAGE (V) _______________________________________________________________________________________ 5 MAX4289 Typical Operating Characteristics (continued) (VCC = 3V, VCM = 0, RL to VCC/2, TA = +25°C, unless otherwise noted.) 1.0V Micropower, SOT23, Operational Amplifier MAX4289 Pin Description PIN NAME FUNCTION SO SOT23 1, 5, 8 5 2 4 IN- Inverting Input 3 3 IN+ Noninverting Input 4 2 GND Ground 6 1 OUT Amplifier Output 7 6 VCC Positive Supply. Bypass with a 0.1µF capacitor to GND. N.C. No Connection. Not internally connected. Detailed Description The MAX4289 consumes ultra-low power (9µA supply current typically) and has a rail-to-rail output stage that is specifically designed for low-voltage operation. The input common-mode voltage range extends from VCC 0.2V to ground, although full rail-to-rail input range is possible with degraded performance. The input offset voltage is typically 200µV. Low-operating supply voltage, low supply current, and rail-to-rail outputs make this operational amplifier an excellent choice for precision or general-purpose, low-voltage, battery-powered systems. IN 500mV/div Rail-to-Rail Output Stage The MAX4289 output stage can drive a 5kΩ load and still swing to within 7mV of the rails. Figure 1 shows the output voltage swing of the MAX4289 configured as a unity-gain buffer, powered from a single 2V supply voltage. The output for this setup typically swings from +0.4mV to (VCC - 0.2mV) with a 100kΩ load. 200µs/div Figure 1. Rail-to-Rail Input/Output Voltage Range SUPPLY CURRENT vs. SUPPLY VOLTAGE Applications Information 25 Power-Supply Considerations 20 SUPPLY CURRENT (µA) The MAX4289 operates from a single 1.0V to 5.5V supply and consumes only 9µA of supply current. A high powersupply rejection ratio of 75dB allows the amplifier to be powered directly off a decaying battery voltage, simplifying design and extending battery life. The MAX4289 is ideally suited for single-cell battery-powered systems. Figures 2 and 3 show the supply current and PSRR as a function of supply voltage and temperature. OUT 500mV/div VIN = 2.0V fIN = 1kHz RL = 100kΩ TA = +85°C 15 TA = +25°C 10 TA = -40°C 5 0 0 1 2 3 4 5 6 SUPPLY VOLTAGE (V) Figure 2. ICC vs. VCC Over the Temperature Range 6 _______________________________________________________________________________________ 1.0V Micropower, SOT23, Operational Amplifier MAX4289 POWER-SUPPLY REJECTION RATIO vs. SUPPLY VOLTAGE 90 TA = +85°C 80 PSRR (dB) RISO MAX4289 TA = -40°C 70 RL CL TA = +25°C 60 50 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 SUPPLY VOLTAGE (V) Figure 3. PSRR vs. VCC Over the Temperature Range Power-Up Settling Time The MAX4289 typically requires 300µs to power-up after VCC is stable. During this startup time, the output is indeterminate. The application circuit should allow for this initial delay. Driving Capacitive Loads The MAX4289 is unity-gain stable for loads up to 200pF. Applications that require greater capacitivedrive capability should use an isolation resistor between the output and the capacitive load (Figure 4). Note that this solution results in a loss of gain accuracy because RISO forms a voltage-divider with the load resistor. AV = RL ≈1 RL + RISO Figure 4. Using a Resistor to Isolate a Capacitive Load from the Op Amp Power Supplies and Layout The MAX4289 operates from a single 1V to 5.5V power supply. Bypass the power with a 0.1µF capacitor to ground. Good layout techniques optimize performance by decreasing the amount of stray capacitance at the op amp’s inputs and outputs. To decrease stray capacitance, minimize trace lengths by placing external components close to the op amp’s pins. Using the MAX4289 as a Comparator Although optimized for use as an operational amplifier, the MAX4289 can also be used as a rail-to-rail I/O comparator (Figure 5). External hysteresis can be used to minimize the risk of output oscillation. The positive feedback circuit, shown in Figure 5, causes the input threshold to change when the output voltage changes state. _______________________________________________________________________________________ 7 MAX4289 1.0V Micropower, SOT23, Operational Amplifier INPUT VOH HYSTERESIS VHI VLO VOH OUTPUT VOL VIN RHYST R1 VCC VOUT MAX4289 R2 VEE VEE Figure 5. Hysteresis Comparator Circuit Chip Information TRANSISTOR COUNT: 557 8 _______________________________________________________________________________________ 1.0V Micropower, SOT23, Operational Amplifier 6LSOT.EPS SOICN.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 _____________________ 9 © 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX4289 Package Information