TC1108 Datasheet, PDF (3/12 Pages) Microchip Technology – 300mA CMOS LDO

2.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 2-1.
TABLE 2-1: PIN FUNCTION TABLE
Pin No.
(3-Pin SOT-223)
1
2
3
Symbol
V_IN
GND
V_OUT
Unregulated supply input.
Ground terminal.
Regulated voltage output.
3.0 DETAILED DESCRIPTION
The TC1108 is a precision, fixed output LDO. Unlike
bipolar regulators, the TC1108’s supply current does
not increase with load current. In addition, V_OUT
remains stable and within regulation over the entire
0mA to I_OUTMAX operating load current range, (an
important consideration in RTC and CMOS RAM
battery back-up applications).
Figure 3-1 shows a typical application circuit.
FIGURE 3-1:
TYPICAL APPLICATION
CIRCUIT
Battery
+
1 _VIN
C1
3
V_{OUT +}
C2
V_OUT
+
1µF _TC1108
1µF
2
–
GND
TC1108
Description
3.1 Output Capacitor
A 1µF (min) capacitor from V_OUT to ground is required.
The output capacitor should have an effective series
resistance greater than 0.1Ω and less than 5.0Ω. A 1µF
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.
© 2002 Microchip Technology Inc.
DS21357B-page 3