Datasheet

 2009-2013 Microchip Technology Inc. DS20002200D-page 19
MCP1804
5.0 FUNCTIONAL DESCRIPTION
The MCP1804 CMOS linear regulator is intended for
applications that need low current consumption while
maintaining output voltage regulation. The operating
continuous load of the MCP1804 ranges from 0 mA to
150 mA. The input operating voltage ranges from 2.0V
to 28.0V, making it capable of operating from a single
12V battery or single and multiple Li-Ion cell batteries.
5.1 Input
The input of the MCP1804 is connected to the source
of the P-Channel PMOS pass transistor. As with all
LDO circuits, a relatively low source impedance
(< 10) is needed to prevent the input impedance from
causing the LDO to become unstable. The size and
type of the capacitor needed depend heavily on the
input source type (battery, power supply) and the
output current range of the application. For most
applications, a 0.1 µF ceramic capacitor will be
sufficient to ensure circuit stability. Larger values can
be used to improve circuit AC performance.
5.2 Output
The maximum rated continuous output current for the
MCP1804 is 150 mA.
A minimum output capacitance of 0.1 µF to 1.0 µF is
required for small signal stability in applications that
have up to 150 mA output current capability. The
capacitor type can be ceramic, tantalum or aluminum
electrolytic.