A good PCB layout for the LTC2859CDD involves keeping the analog and digital grounds separate, using a solid ground plane, and minimizing the length of the traces between the IC and the capacitors. Additionally, it's recommended to place the bypass capacitors as close as possible to the IC's power pins.
To ensure proper power-up and power-down of the LTC2859CDD, it's recommended to follow a specific power-up sequence. First, apply the analog supply voltage (VCC) followed by the digital supply voltage (VDD). During power-down, reverse the sequence. Also, make sure to add a power-on reset circuit to ensure the IC is properly reset during power-up.
The maximum allowed capacitance value for the bypass capacitors depends on the specific application and the desired level of noise filtering. However, as a general rule, it's recommended to use capacitors with a value between 0.1uF and 10uF. Larger capacitance values can cause excessive inrush current during power-up, which may damage the IC.
To troubleshoot issues with the LTC2859CDD, start by verifying the power supply voltages and ensuring that the IC is properly powered up and powered down. Check the input and output signals using an oscilloscope to identify any anomalies. Also, review the PCB layout and ensure that it follows the recommended guidelines. If the issue persists, consult the datasheet and application notes for further guidance.
The LTC2859CDD is rated for operation up to 125°C, but it's recommended to derate the IC's performance at higher temperatures. Consult the datasheet for specific derating guidelines. Additionally, ensure that the PCB and surrounding components are also rated for high-temperature operation.
LTC2859CDD#PBF datasheet
by Linear Technology
