UCC3884N datasheet by Texas Instruments

UCC3884N Frequently Asked Questions (FAQs)

• What is the recommended layout and placement for the UCC3884N?
  The UCC3884N is a high-frequency device, and proper layout and placement are crucial for its operation. TI recommends a 4-layer PCB with a solid ground plane, and the device should be placed close to the input capacitors. The output inductor and diode should be placed close to the device, and the feedback components should be routed away from the high-current paths.
• How do I select the right input and output capacitors for the UCC3884N?
  The input capacitor should be a low-ESR ceramic capacitor with a voltage rating of at least 1.5 times the input voltage. The output capacitor should be a low-ESR ceramic or film capacitor with a voltage rating of at least 1.5 times the output voltage. The capacitance value should be chosen based on the desired output ripple and transient response.
• What is the maximum output current that the UCC3884N can deliver?
  The UCC3884N can deliver up to 4A of output current, but this is dependent on the input voltage, output voltage, and thermal conditions. The device should be operated within its recommended operating conditions to ensure reliable operation.
• How do I compensate the UCC3884N for stability?
  The UCC3884N requires a compensation network to ensure stability. TI recommends a type-III compensation network, which consists of resistors and capacitors connected between the COMP pin and the output voltage. The values of these components should be chosen based on the desired transient response and stability margin.
• What is the purpose of the SS pin on the UCC3884N?
  The SS pin is the soft-start pin, which allows the user to control the startup sequence of the device. By connecting a capacitor to the SS pin, the user can slow down the startup sequence and reduce the inrush current.