TC1264
DS21375D-page 6 2010 Microchip Technology Inc.
4.0 DETAILED DESCRIPTION
The TC1264 is a precision, fixed output LDO. Unlike
bipolar regulators, the TC1264’s supply current does
not increase with load current. In addition, V
OUT
remains stable and within regulation over the entire
0mA to I
LOADMAX
load current range (an important
consideration in RTC and CMOS RAM battery back-up
applications).
Figure 4-1 shows a typical application circuit.
FIGURE 4-1: Typical Application Circuit.
4.1 Output Capacitor
A 1 µF (min) capacitor from V
OUT
to ground is required.
The output capacitor should have an effective series
resistance greater than 0.1 and less than 5. A 1 µF
capacitor should be connected from V
IN
to GND if there
is more than 10 inches of wire between the regulator
and the AC filter capacitor, or if a battery is used as the
power source. Aluminum electrolytic or tantalum
capacitor types can be used. (Since many aluminum
electrolytic capacitors freeze at approximately -30°C,
solid tantalums are recommended for applications
operating below -25°C.) When operating from sources
other than batteries, supply-noise rejection and
transient response can be improved by increasing the
value of the input and output capacitors and employing
passive filtering techniques.
TC1264
V
IN
V
OUT
C
1
1µF
GND
V
OUT
V
IN
SHDN
+