JAJSA34K November 2002 – December 2016 LP2996-N , LP2996A
PRODUCTION DATA.
There are several recommendations for the LP2996-N and LP2996A input power supply. Although not required, TI recommends an input capacitor for improved performance during large load transients to prevent the input rail from dropping. The input capacitor must be placed as close as possible to the PVIN pin.
A typical value recommended for aluminum electrolytic capacitors is 50 µF. Ceramic capacitors can also be used, a value approximately 10 µF with X5R or better would be an ideal choice. The input capacitance can be reduced if the LP2996-N or LP2996A is placed close to the bulk capacitance from the output of the 2.5-V DC-DC converter. If the two supply rails (AVIN and PVIN) are separated then the 47-µF capacitor must be placed as close to possible to the PVIN rail. An additional 0.1-µF ceramic capacitor can be placed on the AVIN rail to prevent excessive noise from coupling into the device.