INA848ID

The INA848 is a fixed-gain instrumentation amplifier optimized for high-precision measurements, such as very-small, fast, differential input signals. TI's superbeta topology provides a very low input bias current and current noise. The well-matched transistors help achieve a very low offset and offset drift. Matching of the internal resistors yields a high common-mode rejection ratio of 132 dB across the full input-voltage range, and a very low gain drift error of 5 ppm/⁰C (max). The current-feedback topology of the INA848 produces a wide bandwidth of 2.8 MHz at a fixed gain of 2000, thereby eliminating the need for subsequent gain stages. The very-low noise floor of 1.3 nV/√Hz minimizes the impact on the equivalent number of bits (ENOB) when interfacing with high-resolution analog-to-digital converters (ADCs). The INA848 provides the flexibility of adding filters between the gain stages (pins 2 and 3) to maintain an adequate signal integrity. These unique features of the INA848 make this device an excellent choice for applications requiring high-precision measurements, such as high-end medical instrumentation, electroencephalography, vibration sensing, and displacement measurements. This device is designed for 8-V to 36-V single supplies, or ±4.8 to ±18-V on dual supplies.

Applications

• Surgical equipment
• Electrocardiogram (ECG)
• Ultrasound scanner
• Semiconductor test
• Data acquisition (DAQ)
• Vibrational analysis

Key features

• Fixed gain of 2000 V/V
• Access to internal nodes for filtering
• Ultra-low noise: 1.5 nV/√Hz input voltage noise (maximum)
• Precision super-beta input performance:
• Low offset voltage: 35 μV (maximum)
• Low offset voltage drift: 0.45 μV/°C (maximum)
• Low input bias current: 25 nA (typical)
• Low gain drift: 5 ppm/°C (maximum)
• Bandwidth: 2.8 MHz
• Slew rate: 45 V/μs
• Common-mode rejection: 132 dB (minimum)
• Supply range:
• Single supply: 8 V to 36 V
• Dual supply: ±4 V to ±18 V
• Specified temperature range: -40°C to +125°C
• Package: 8-pin SOIC