A good PCB layout for the LT1120 involves keeping the input and output capacitors close to the device, using a solid ground plane, and minimizing trace lengths and widths to reduce noise and EMI. A 4-layer PCB with a dedicated power plane and a solid ground plane is recommended.
To ensure stability, make sure to follow the recommended component values and PCB layout guidelines. Also, ensure that the output capacitor has a low ESR and is properly decoupled from the input capacitor. Additionally, avoid using capacitors with high ESL and ESR values.
The maximum input voltage of the LT1120 is 15V, but it's recommended to operate it within the specified input voltage range of 3.5V to 12V for optimal performance and reliability.
The LT1120 is rated for operation up to 125°C, but its performance and reliability may degrade at high temperatures. It's recommended to derate the output current and ensure proper heat sinking to maintain reliability in high-temperature environments.
The output voltage ripple of the LT1120 can be calculated using the formula: ΔVout = (Iout * ESL) / (Cout * fsw), where Iout is the output current, ESL is the equivalent series inductance of the output capacitor, Cout is the output capacitance, and fsw is the switching frequency.
LT1120ACN8#PBF datasheet
by Linear Technology
