A good PCB layout for the LT1491ACN involves keeping the input and output traces short and separate, using a solid ground plane, and placing the bypass capacitors close to the device. A 4-layer PCB with a dedicated power plane and a dedicated ground plane is recommended.
To ensure stability, make sure to follow the recommended compensation network, use a minimum output capacitance of 10uF, and avoid capacitive loads. Also, ensure that the input and output voltages are within the recommended operating range.
The maximum power dissipation of the LT1491ACN is dependent on the package type and the ambient temperature. For the N package, the maximum power dissipation is 1.4W at 25°C ambient temperature. However, it is recommended to derate the power dissipation based on the ambient temperature and the thermal resistance of the package.
While the LT1491ACN can be used as a voltage regulator, it is not recommended due to its limited output current capability and lack of built-in short-circuit protection. It is primarily designed as a high-speed, low-noise op-amp.
To reduce noise, use a low-noise power supply, add bypass capacitors to the power pins, and keep the input and output traces away from noisy signals. Also, consider using a shielded enclosure and a low-noise op-amp configuration such as a differential amplifier.
LT1491ACN#PBF datasheet
by Linear Technology
