Microchip MCP6002T-E/MC Dual Op-Amp: Features and Application Circuits
The Microchip MCP6002T-E/MC is a dual operational amplifier (op-amp) that stands out for its excellent combination of performance, low power consumption, and cost-effectiveness. It is part of the MCP6002 family, which is designed using Microchip's advanced CMOS technology. This op-amp is particularly well-suited for battery-powered devices, portable equipment, and general-purpose analog signal conditioning due to its low quiescent current of 100 µA (typical) per amplifier and rail-to-rail input and output operation.
A key feature of this device is its wide supply voltage range, from 1.8V to 6.0V, making it compatible with both 3.3V and 5V systems and even two-cell battery configurations. Despite its low power draw, it offers a respectable gain bandwidth product of 1 MHz and a typical slew rate of 0.6 V/µs. Furthermore, it is characterized by low input bias current and stable operation with a high capacitive load. The MCP6002T-E/MC is offered in an 8-pin DFN package, ideal for space-constrained applications, and is specified over the extended industrial temperature range (-40°C to +125°C).
Key Application Circuits
1. Non-Inverting Amplifier:
This is one of the most fundamental circuits for signal amplification. The input signal is applied to the non-inverting pin (+), providing a high input impedance. The closed-loop gain is set by two resistors (R1 and R2) and is given by Av = 1 + (R2 / R1). This configuration is perfect for amplifying sensor signals (e.g., from thermistors or photodiodes) without loading the source.
2. Active Low-Pass Filter (1st Order):
By adding a capacitor in parallel with the feedback resistor (R2) in a standard inverting or non-inverting configuration, the op-amp becomes a simple active low-pass filter. This circuit attenuates high-frequency noise while allowing lower frequency signals to pass, which is crucial for cleaning up analog signals before they are digitized by a microcontroller's ADC.
3. Voltage Follower (Unity-Gain Buffer):
In this configuration, the output is directly connected to the inverting input (-), creating a feedback factor of 1. The result is a gain of exactly 1. The primary purpose of this circuit is not voltage gain but impedance transformation. It provides a very high input impedance to the source and a very low output impedance, effectively isolating a sensitive signal source from a heavy load.
4. Photodiode Transimpedance Amplifier (TIA):
The MCP6002T-E/MC's low input bias current makes it an excellent choice for converting the small output current of a photodiode or other current-output sensor into a measurable voltage. In this circuit, the photodiode is connected between the inverting input and ground, and a feedback resistor (Rf) is connected from the output to the inverting input. The output voltage is Vout = Ipd × Rf. The rail-to-rail output swing allows for a wide dynamic range of measurement.
5. Dual-Supply to Single-Supply Interface (Virtual Ground):
In single-supply systems (e.g., a 5V rail), a virtual ground circuit at half the supply voltage (2.5V) is often needed to bias AC signals so they can swing above and below this reference point. One amplifier of the MCP6002 can be configured as a voltage follower to create a low-impedance, stable virtual ground reference from a simple resistor divider, which is then used by the second amplifier for signal processing.
The Microchip MCP6002T-E/MC is a remarkably versatile dual op-amp that delivers essential performance characteristics—low power, rail-to-rail operation, and wide voltage range—in a miniature package. Its balance of efficiency and functionality makes it an ideal building block for a vast array of analog design needs in modern portable and embedded systems, from simple amplification and filtering to precise sensor signal conditioning.
Keywords:
1. Low Power Consumption
2. Rail-to-Rail Input/Output
3. Operational Amplifier
4. Sensor Signal Conditioning
5. Portable Applications
