TC1107 MICROCHIP [Microchip Technology], TC1107 Datasheet - Page 4

• Manufacturer Part Number: TC1107
• Description: 300mA CMOS LDO with Shutdown and VREF Bypass
• Manufacturer: MICROCHIP [Microchip Technology]

TC1107
3.0
The TC1107 is a precision regulator available in fixed
voltages. Unlike bipolar regulators, the TC1107’s
supply current does not increase with load current. In
addition, V
over the entire 0mA to I
range, (an important consideration in RTC and CMOS
RAM battery back-up applications).
Figure 3-1 shows a typical application circuit. The
regulator is enabled any time the shutdown input
(SHDN) is at or above V
when SHDN is at or below V
controlled by a CMOS logic gate, or I/O port of a
microcontroller. If the SHDN input is not required, it
should be connected directly to the input supply. While
in shutdown, supply current decreases to 0.05µA
(typical), V
FIGURE 3-1:
DS21356B-page 4
V
OUT
C
(Optional)
BYPASS
470pF
DETAILED DESCRIPTION
OUT
OUT
+
falls to zero.
C2
1µF
remains stable and within regulation
1
2
3
4
V
GND
NC
Bypass
OUT
TC1107
TYPICAL APPLICATION
CIRCUIT
OUT
IH
, and shutdown (disabled)
MAX
SHDN
V
NC
NC
Shutdown Control
(from Power Control Logic)
IN
operating load current
IL
8
7
6
5
. SHDN may be
+
C1
1µF
Battery
+
–
3.1
A 1µF (min) capacitor from V
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
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.
3.2
A 470pF capacitor connected from the Bypass input to
ground reduces noise present on the internal
reference, which in turn significantly reduces output
noise. If output noise is not a concern, this input may be
left unconnected. Larger capacitor values may be
used, but results in a longer time period to rated output
voltage when power is initially applied.
Output Capacitor
Bypass Input
©
2002 Microchip Technology Inc.
OUT
to ground is required.
IN
to GND if there