FAN4931 Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Features Description 200µA Supply Current per Amplifier FAN4931 is an ultra-low cost voltage feedback amplifier with CMOS inputs that consumes only 200µA of supply current, while providing ±33mA of output short-circuit current. This amplifier is designed to operate from 2.5V to 5V supplies. The common-mode voltage range extends beyond the negative and positive rails. Fully Specified at +2.7V and +5V Supplies 3.7MHz Bandwidth Output Swing to within 10mV of Either Rail Input Voltage Range Exceeds the Rails 3V/µs Slew Rate The FAN4931 is designed on a CMOS process and provides 3.7MHz of bandwidth and 3V/μs of slew rate at a supply voltage of 5V. The combination of low power, rail-to-rail performance, low-voltage operation, and tiny package options make this amplifier well suited for use in general-purpose and battery-powered applications. 25nV/√Hz Input Voltage Noise FAN4931 Competes with LMV931; Available in SC70-5 Package Applications Portable / Battery-Powered Applications PCMCIA, USB Mobile Communications, Cellular Phones, Pagers Notebooks and PDAs Sensor Interface A/D Buffer Active Filters Signal Conditioning Portable Test Instruments Figure 1. Frequency vs. Gain Ordering Information Part Number FAN4931IP5X Operating Temperature Range -40 to +85°C Package 5-Lead SC70 Package Eco Status Green Packing Method Tape and Reel (3000) For Fairchild’s definition of Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html. © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 www.fairchildsemi.com FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier November 2009 Figure 2. Typical Application Pin Configurations FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Typical Application Figure 3. Pin Assignments Pin Assignments Pin # Name Description 1 +IN Positive Input 2 -VS Negative Supply 3 -IN Negative Input 4 VOUT Output 5 +VS Positive Supply © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 www.fairchildsemi.com 2 Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Functional operation under any of these conditions is NOT implied. Performance and reliability are guaranteed only if operating conditions are not exceeded. Symbol Parameter VCC Supply Voltage VIN Input Voltage Range TJ Junction Temperature TSTG Storage Temperature Max. Unit 0 6 V -VS-0.5 +VS+0.5 V +150 °C -65 TL Lead Soldering, 10 Seconds ΘJA Thermal Resistance ESD Min. (1) Electrostatic Discharge Capability +150 °C +300 °C 331 °C/W Human Body Model, JESD22-A114 5 Charged Device Model, JESD22-C101 2 kV Note: 1. Package thermal resistance JEDEC standard, multi-layer test boards, still air. Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings. Symbol Parameter Min. Max. Unit +VS Supply Voltage 2.30 5.25 V TA Operating Temperature Range -40 +85 °C © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Absolute Maximum Ratings www.fairchildsemi.com 3 VS=+2.7V, G=2, RL=10kΩ to VS/2, RF=5kΩ; unless otherwise noted. Symbol Parameter Conditions Min. Typ. Max. Units Frequency Domain Response UGBW BW SS GBWP G=+1 -3dB Bandwidth Gain Bandwidth Product 4 MHz 2.5 MHz 4 MHz Time Domain Response tR, fF Rise and Fall Time VO=1.0V Step 300 ns OS Overshoot VO=1.0V Step 5 % SR Slew Rate VO=3V Step, G=-1 3 V/µs Distortion and Noise Response HD2 2nd Harmonic Distortion VO=1VPP, 10kHz -66 dBc HD3 3rd Harmonic Distortion VO=1VPP, 10kHz -67 dBc THD Total Harmonic Distortion VO=1VPP, 10kHz 0.1 % 26 nV/√Hz en Input Voltage Noise DC Performance VIO Input Offset Voltage dVIO Average Drift Ibn PSRR AOL IS (2) -6 Input Bias Current Power Supply Rejection Ratio (2) Open-Loop Gain DC 50 DC Supply Current per Amplifier (2) 0 +6 mV 2.1 µV/°C 5 pA 73 dB 98 dB 200 300 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Electrical Specifications at +2.7V µA Input Characteristics RIN Input Resistance 10 GΩ CIN Input Capacitance 1.4 pF -0.3 to 2.6 V 50 65 dB 0.03 0.01 to 2.69 CMIR Input Common Mode Voltage Range CMRR Common Mode Rejection Ratio (2) DC, VCM=OV to 2.2V Output Characteristics VO Output Voltage Swing (2) RL=10kΩ to VS/2 RL=1kΩ to VS/2 ISC Short-Circuit Output Current VS Power Supply Operating Range 0.05 to 2.55 2.65 V +34/-12 mA 2.5 to 5.5 V Note: 2. 100% tested at TA=25°C. © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 www.fairchildsemi.com 4 VS=+5V, G=2, RL=10kΩ to VS/2, RF= 5kΩ; unless otherwise noted. Symbol Parameter Conditions Min. Typ. Max. Units Frequency Domain Response UGBW BW SS GBWP G=+1 -3dB Bandwidth Gain Bandwidth Product 3.7 MHz 2.3 MHz 3.7 MHz Time Domain Response tR, fF Rise and Fall Time VO=1.0V Step 300 ns OS Overshoot VO=1.0V Step 5 % SR Slew Rate VO=3V Step, G=-1 3 V/µs Distortion and Noise Response HD2 2nd Harmonic Distortion VO=1VPP, 10kHz -80 dBc HD3 3rd Harmonic Distortion VO=1VPP, 10kHz -80 dBc THD Total Harmonic Distortion VO=1VPP, 10kHz 0.02 % 25 nV/√Hz en Input Voltage Noise DC Performance VIO Input Offset Voltage dVIO Average Drift Ibn PSRR AOL IS (3) -8 Input Bias Current Power Supply Rejection Ratio (3) Open-Loop Gain DC 50 DC Supply Current per Amplifier (3) 0 +8 mV 2.9 µV/°C 5 pA 73 dB 102 dB 200 300 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Electrical Specifications at +5V µA Input Characteristics RIN Input Resistance 10 GΩ CIN Input Capacitance 1.2 pF -0.3 to 5.3 V dB CMIR Input Common Mode Voltage Range CMRR Common Mode Rejection Ratio Typical (3) DC, VCM=0V to VS 58 73 RL=10kΩ to VS/2 0.03 0.01 to 4.99 Output Characteristics VO Output Voltage Swing (3) RL=1kΩ to VS/2 ISC Short-Circuit Output Current VS Power Supply Operating Range 0.1 to 4.9 4.95 V ±33 mA 2.5 to 5.5 V Note: 3. 100% tested at TA=25°C. © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 www.fairchildsemi.com 5 VS=+2.7, G=2, RL=10kΩ to VS/2, RF=5kΩ; unless otherwise noted. Figure 4. Non-Inverting Frequency Response (+5) Figure 5. Inverting Frequency Response (+5V) Figure 6. Non-Inverting Frequency Response Figure 7. Inverting Frequency Response Figure 8. Frequency Response vs. CL Figure 9. Frequency Response vs. RL Figure 10. Large Signal Frequency Response (+5V) Figure 11. Open-Loop Gain and Phase vs. Frequency © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Typical Performance Characteristics www.fairchildsemi.com 6 VS=+2.7, G=2, RL=10kΩ to VS/2, RF=5kΩ; unless otherwise noted. Figure 12. 2nd and 3rd Harmonic Distortion Figure 13. 2nd Harmonic Distortion vs. VO Figure 14. 3rd Harmonic Distortion vs. VO Figure 15. CMRR VS=5V Figure 16. PSRR VS=5V Figure 17. Output Swing vs. Load Figure 18. Pulse Response vs. Common-Mode Voltage Figure 19. Input Voltage Noise © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Typical Performance Characteristic www.fairchildsemi.com 7 General Description Overdrive Recovery The FAN4931 amplifier is a single-supply, generalpurpose, voltage-feedback amplifier, fabricated on a biCMOS process. It features a rail-to-rail input and output and is unity gain stable. The typical non-inverting circuit schematic is shown in Figure 20. Overdrive of an amplifier occurs when the output and/or input ranges are exceeded. The recovery time varies based on whether the input or output is overdriven and by how much the range is exceeded. The FAN4931 typically recovers in less than 500ns from an overdrive condition. Figure 22 shows the FAN4931 amplifier in an overdriven condition. Figure 20. Typical Non-Inverting Configuration Figure 22. Overdrive Recovery Input Common-Mode Voltage Driving Capacitive Loads The common-mode input range extends to 300mV below ground and to 100mV above VS in single-supply operation. Exceeding these values does not cause phase reversal; however, if the input voltage exceeds the rails by more than 0.5V, the input ESD devices begin to conduct. The output stays at the rail during this overdrive condition. If the absolute maximum input VIN (700mV beyond either rail) is exceeded, externally limit the input current to ±5mA, as shown in Figure 21. Figure 8 illustrates the response of the amplifier. A small series resistance (RS) at the output, illustrated in Figure 23, improves stability and settling performance. RS values in Figure 8 were chosen to achieve maximum bandwidth with less than 2dB of peaking. For maximum flatness, use a larger RS. Capacitive loads larger than 500pF require the use of RS. Figure 21. Circuit for Input Current Protection Figure 23. Typical Topology for Driving a Capacitive Load Driving a capacitive load introduces phase-lag into the output signal, which reduces phase margin in the amplifier. The unity gain follower is the most sensitive configuration. In a unity gain follower configuration, the amplifier requires a 300Ω−series resistor to drive a 100pF load. Power Dissipation The maximum internal power dissipation allowed is directly related to the maximum junction temperature. If the maximum junction temperature exceeds 150°C, performance degradation occurs. If the maximum junction temperature exceeds 150°C for an extended time, device failure may occur. © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Application Information www.fairchildsemi.com 8 General layout and supply bypassing play major roles in high-frequency performance. Fairchild evaluation boards help guide high-frequency layout and aid in device testing and characterization. Follow the steps below as a basis for high-frequency layout: Evaluation Board Information The following evaluation board is available to aid in the testing and layout of this device. Evaluation Board 1. Include 6.8μF and 0.01μF ceramic capacitors. 2. Place the 6.8μF capacitor within 0.75 inches of the power pin. FAN4931-011 3. Place the 0.01μF capacitor within 0.1 inches of the power pin. Description Single-Channel, Dual-Supply, 5 -Lead SC70 Products FAN4931IP5X Evaluation board schematics are shown in Figure 24; layouts are shown in Figures 25-26. 4. Remove the ground plane under and around the part, especially near the input and output pins, to reduce parasitic capacitance. Minimize all trace lengths to reduce series inductances. Refer to the evaluation board layouts shown in Figures 24-26 for more information. When evaluating only one channel, complete the following on the unused channel: 1. Ground the non-inverting input. 2. Short the output to the inverting input. FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Layout Considerations Figure 24. Evaluation Board Schematic Board Layout Information Figure 25. Top Side © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 Figure 26. Bottom Side www.fairchildsemi.com 9 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier Physical Dimensions Figure 27. 5-Lead SC70 Package Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 www.fairchildsemi.com 10 FAN4931 — Ultra-Low Cost, Rail-to-Rail I/O, CMOS Amplifier © 2008 Fairchild Semiconductor Corporation FAN4931 • Rev. 1.0.0 www.fairchildsemi.com 11