OP27GP
OP27GP Precision Operational Amplifier
Overview
The OP27GP is a high-precision operational amplifier that combines the exceptional offset and drift characteristics of the OP07 with improved speed and noise performance. Designed for precision instrumentation applications, this amplifier delivers outstanding accuracy in both DC and AC signal conditioning. The device features ultra-low noise, high gain, and excellent dynamic response, making it particularly suitable for amplifying low-level signals in demanding measurement systems.
With its combination of precision DC characteristics and AC performance, the OP27GP bridges the gap between traditional precision amplifiers and high-speed devices. The amplifier is pin-compatible with industry-standard parts like the 725, OP07, and 5534A, allowing for easy upgrades in existing designs while providing superior performance characteristics.
Key Features
- Ultra-Low Noise Performance: 3.5 nV/√Hz at 10 Hz with 80 nV p-p noise (0.1 Hz to 10 Hz)
- Precision DC Characteristics: Input offset voltage as low as 25 μV with maximum drift of 0.6 μV/°C
- High Gain: Open-loop gain of 1.8 million (126 dB)
- Excellent Dynamic Performance: Gain-bandwidth product of 8 MHz with 2.8 V/μs slew rate
- Superior Common-Mode Rejection: 126 dB at ±11V common-mode voltage
- Low 1/f Noise Corner: Just 2.7 Hz for improved low-frequency performance
- Flexible Packaging: Available in standard packages and die form for custom integration
Applications
The OP27GP's combination of precision and speed makes it ideal for a wide range of demanding applications:
Test and Measurement Equipment
- Precision instrumentation amplifiers
- Low-noise signal conditioning circuits
- Data acquisition front ends
- Strain gauge amplifiers
Medical Electronics
- ECG and EEG amplification systems
- Medical imaging equipment
- Biomedical sensors
Industrial Systems
- Process control instrumentation
- High-accuracy transducer interfaces
- Precision current sensing
Audio Equipment
- Professional audio mixing consoles
- High-end microphone preamplifiers
- Low-noise audio processing
Electrical Characteristics
The following table summarizes the key electrical specifications at VS = ±15V, TA = 25°C unless otherwise noted:
DC Characteristics
- Input Offset Voltage: 25 μV (max), 10 μV (typ)
- Input Offset Voltage Drift: 0.2 μV/°C (typ), 0.6 μV/°C (max)
- Input Bias Current: 15 nA (max), 7 nA (typ)
- Input Offset Current: 10 nA (max), 3 nA (typ)
- Common Mode Rejection Ratio: 126 dB (min), 130 dB (typ)
- Power Supply Rejection Ratio: 120 dB (min), 126 dB (typ)
- Open-Loop Voltage Gain: 1.8 million (typ) at RL = 2kΩ
- Input Voltage Range: ±12V (min) at VS = ±15V
AC Characteristics
- Gain-Bandwidth Product: 8 MHz (typ)
- Slew Rate: 2.8 V/μs (typ)
- Input Voltage Noise: 3 nV/√Hz at 1 kHz (typ)
- Input Current Noise: 1.5 pA/√Hz at 1 kHz (typ)
- 1/f Noise Corner: 2.7 Hz (typ)
- Total Harmonic Distortion: 0.0003% at 1 kHz (typ)
Power Characteristics
- Supply Voltage Range: ±4V to ±18V
- Supply Current: 4 mA (typ), 5 mA (max)
- Power Consumption: 120 mW (typ) at ±15V
Package Information
The OP27GP is available in multiple package options to suit different application requirements:
Standard Packages
- 8-Pin PDIP (Plastic Dual In-line Package):
- Package Code: P
- Dimensions: 9.81mm x 6.35mm x 3.3mm
- Lead Pitch: 2.54mm
- 8-Pin SOIC (Small Outline Integrated Circuit):
- Package Code: S
- Dimensions: 4.9mm x 3.9mm x 1.25mm
- Lead Pitch: 1.27mm
Special Package Options
- TO-99 Metal Can Package:
- Package Code: H
- Dimensions: 9.08mm diameter x 4.7mm height
- 8-lead configuration with hermetic sealing
- Die Form:
- Available for hybrid and custom module applications
- Die dimensions: 1.52mm x 1.52mm x 0.33mm
- Backside metallized for die attachment
Design Considerations
Thermal Management
The OP27GP's precision characteristics require careful thermal management. For optimal performance:
- Maintain symmetrical thermal environments for input transistors
- Use ground planes to minimize thermal gradients
- Consider thermal isolation in high-precision applications
PCB Layout Guidelines
Proper board layout is essential to achieve the specified performance:
- Use short, direct traces for input connections
- Implement guard rings around high-impedance inputs
- Place bypass capacitors (0.1 μF ceramic) close to power pins
- Minimize parasitic capacitance at the amplifier inputs
Compensation and Stability
The OP27GP is internally compensated for unity-gain stability. For special applications:
- Additional compensation may be needed for capacitive loads > 100pF
- Use series output resistors for driving cables or large capacitive loads
- Consider bandwidth limiting in high-gain applications to optimize noise performance
