The Microchip’s MCP6471 family of operational amplifiers (op amps) has low input bias current (150 pA, typical at 125°C) and rail-to-rail input and output operation
MCP6471/2/4Typical Application C2 R2 VOUT ID1 VDD – Light D1 MCP647X + Photodiode Amplifier DS20002324C-page 2 2012-2013 Microchip Technology Inc. Document Outline Package Types Typical Application 1.0 Electrical Characteristics 1.1 Absolute Maximum Ratings 1.2 Specifications TABLE 1-1: DC Electrical Specifications TABLE 1-2: AC Electrical Specifications TABLE 1-3: Temperature Specifications 1.3 Test Circuits FIGURE 1-1: AC and DC Test Circuit for Most Specifications. 2.0 Typical Performance Curves FIGURE 2-1: Input Offset Voltage. FIGURE 2-2: Input Offset Voltage Drift. FIGURE 2-3: Input Offset Voltage vs. Common Mode Input Voltage. FIGURE 2-4: Input Offset Voltage vs. Common Mode Input Voltage. FIGURE 2-5: Input Offset Voltage vs. Output Voltage. FIGURE 2-6: Input Offset Voltage vs. Power Supply Voltage. FIGURE 2-7: Input Noise Voltage Density vs. Frequency. FIGURE 2-8: Input Noise Voltage Density vs. Common Mode Input Voltage. FIGURE 2-9: CMRR, PSRR vs. Frequency. FIGURE 2-10: CMRR, PSRR vs. Ambient Temperature. FIGURE 2-11: Input Bias, Offset Currents vs. Ambient Temperature. FIGURE 2-12: Input Bias Current vs. Common Mode Input Voltage. FIGURE 2-13: Quiescent Current vs. Ambient Temperature. FIGURE 2-14: Quiescent Current vs. Common Mode Input Voltage. FIGURE 2-15: Quiescent Current vs. Common Mode Input Voltage. FIGURE 2-16: Quiescent Current vs. Power Supply Voltage. FIGURE 2-17: Open-Loop Gain, Phase vs. Frequency. FIGURE 2-18: DC Open-Loop Gain vs. Ambient Temperature. FIGURE 2-19: Gain Bandwidth Product, Phase Margin vs. Ambient Temperature. FIGURE 2-20: Gain Bandwidth Product, Phase Margin vs. Ambient Temperature. FIGURE 2-21: Output Short Circuit Current vs. Power Supply Voltage. FIGURE 2-22: Output Voltage Swing vs. Frequency. FIGURE 2-23: Output Voltage Headroom vs. Output Current. FIGURE 2-24: Output Voltage Headroom vs. Output Current. FIGURE 2-25: Output Voltage Headroom vs. Ambient Temperature. FIGURE 2-26: Output Voltage Headroom vs. Ambient Temperature. FIGURE 2-27: Slew Rate vs. Ambient Temperature. FIGURE 2-28: Small Signal Non-Inverting Pulse Response. FIGURE 2-29: Small Signal Inverting Pulse Response. FIGURE 2-30: Large Signal Non-Inverting Pulse Response. FIGURE 2-31: Large Signal Inverting Pulse Response. FIGURE 2-32: The MCP6471/2/4 Shows No Phase Reversal. FIGURE 2-33: Closed Loop Output Impedance vs. Frequency. FIGURE 2-34: Measured Input Current vs. Input Voltage (below VSS). FIGURE 2-35: Channel-to-Channel Separation vs. Frequency (MCP6472/4 only). 3.0 Pin Descriptions TABLE 3-1: Pin Function Table 3.1 Analog Outputs 3.2 Analog Inputs 3.3 Power Supply Pins 3.4 Exposed Thermal Pad (EP) 4.0 Application Information 4.1 Inputs FIGURE 4-1: Simplified Analog Input ESD Structures. FIGURE 4-2: Protecting the Analog Inputs. FIGURE 4-3: Protecting the Analog Inputs. 4.2 Rail-to-Rail Output 4.3 Capacitive Loads FIGURE 4-4: Output Resistor, RISO Stabilizes Large Capacitive Loads. FIGURE 4-5: Recommended RISO Values for Capacitive Loads. 4.4 Supply Bypass 4.5 Unused Op Amps FIGURE 4-6: Unused Op Amps. 4.6 PCB Surface Leakage FIGURE 4-7: Example Guard Ring Layout for Inverting Gain. 4.7 Application Circuits FIGURE 4-8: Photovoltaic Mode Detector. FIGURE 4-9: Photoconductive Mode Detector. FIGURE 4-10: Second-Order, Low-Pass Butterworth Filter with Sallen-Key Topology. FIGURE 4-11: Second-Order, Low-Pass Butterworth Filter with Multiple-Feedback Topology. FIGURE 4-12: pH Electrode Amplifier. 5.0 Design Aids 5.1 SPICE Macro Model 5.2 FilterLab Software 5.3 MAPS (Microchip Advanced Part Selector) 5.4 Analog Demonstration and Evaluation Boards 5.5 Application Notes 6.0 Packaging Information 6.1 Package Marking Information Appendix A: Revision History Product Identification System Trademarks Worldwide Sales and Service