Description

AD8421 10MHz 35V/us High Speed Instrument Amplifier Module Ultra-low Noise/Bias Current Weak Signal Amplifier

Description:
- AD8421 is a low-cost, low-power, ultra-low noise, and ultra-low bias current high-speed instrument amplifier. This module can adjust the bias voltage through onboard sliding, and is shipped with a shielding cover and gain sliding to meet different user needs. Users can choose whether to solder gain slip or not. AD8421 has a high CMRR and a bandwidth of 10 MHz, with a swing rate of 35V/μs, making it suitable for various signal conditioning and data acquisition applications, especially in applications that require high channel number multiplexing systems. It is also suitable for demanding applications such as vibration analysis, and only one resistor is needed to set the gain to 1 to 10000.

Specification:
- Model: AD8421
- Module type: weak signal amplifier
- Power supply: ±3V to ±16V
- Working current: ±3mA
- Module bandwidth: 10MHz, G=1 for AD8421; 15MHz, G=1 for AD8429
- Swing rate: 35V/μs for AD8421; 22V/μs for AD8429
- Gain range: 1 - 10000, default 11X for AD8421; default 7X for AD8429
- Gain calculation formula: G=1+(9.9kohm/RG) for AD8421; G=1+(6kohm/RG) for AD8429
- Output transfer function: VOUT = G x (VIN+ - VIN-) + VREF
- Input impedance: high impedance
- Bias voltage adjustment range: power supply - 2V
- Module protection: power supply anti-reverse connection
- Module features: power indicators, support differential/single-end input, adjustable bias
- Application: precision data acquisition system, microphone preamplifier, vibration analysis, multiplexing input application, ADC driver, etc.
- Module weight: 20g
- PCB size: 50 x 50mm
- Connector: SMA connector

Precaution:
- The module is powered by dual power sources, with V+, GND, and V- all connected, and the power supply voltage should not exceed ±18V.
- Due to the module being a high-precision device, it is recommended to use a low ripple power supply to avoid unnecessary interference.
- The module is shipped with a fixed gain by default. If you need to adjust the amplification factor, you can replace the R2 resistor or remove the R2 soldering R1 slide by yourself.
- It is recommended to use good wire to input and output signals, and observe the effect with an oscilloscope. Poor contact or poor quality wire may cause signal attenuation or excessive noise.

FAQ:
Q: Why is there no signal output when I input signal from IN-?
A: The module is a differential input. If a single-ended signal is input, another input needs to be grounded, and a jumper cap can be used to short circuit the input pin.

Q: Is the module output noise high?
A: The output noise may come from power ripple, input signal itself, poor signal wire contact, or external magnetic field interference, and the module will not generate noise on its own.

Package Included:
- 1 x Amplifier Module