ZHCSD40P April 2012 – January 2024 LP5907
PRODUCTION DATA
An input capacitor is required for stability. The input capacitor must be at least equal to, or greater than, the output capacitor for good load transient performance. Connect at least a 1µF capacitor between the LP5907 input pin and ground for stable operation over the full load current range. Basically, having more output capacitance than input is acceptable, as long as the input is at least 1µF.
The input capacitor must be located a distance of not more than 1cm from the input pin and returned to a clean analog ground. Any good quality ceramic, tantalum, or film capacitor can be used at the input.
To provide stable operation, good PCB practices must be used to minimize ground impedance and to keep input inductance low. If these conditions cannot be met, or if long leads are used to connect the battery or other power source to the LP5907, increase the input capacitor to at least 10µF. Also, tantalum capacitors can suffer catastrophic failures resulting from surge current when connected to a low-impedance source of power (such as a battery or a very large capacitor). If a tantalum capacitor is used at the input, verify by the manufacturer that the capacitor has a surge current rating sufficient for the application. The initial tolerance, applied voltage derating, and temperature coefficient must all be considered when selecting the input capacitor to make sure that the actual capacitance is never less than 0.7µF over the entire operating range.