2002 Microchip Technology Inc.
DS21436B-page 1
M
TC56
Features
Low Dropout Voltage: 200mV typ. at 80mA,
380mV typ. at 160mA
High Output Current: 180mA (V
OUT
= 5.0V)
High Accuracy Output Voltage (2%)
Low Power Consumption: 11
A (Oper.),
0.1
A (Shutdown)
Low Temperature Drift (100ppm/C typ.)
Excellent Line Regulation (0.2%/V typ.)
Space Saving 5-Pin SOT-23A Package
Short Circuit Protection
Standard 2.5V, 3.0V and 3.3V Output Voltages
Applications
Battery Powered Devices
Cameras and Portable Video Equipment
Pagers and Cellular Phones
Solar Powered Instruments
Consumer Products
Device Selection Table
*Other output voltages are available. Please contact
Microchip Technology Inc. for details.
Package Type
General Description
The TC56 is a low supply current (11
A typical at
V
OUT
= 3V), low dropout CMOS linear regulator, with a
10V maximum input voltage range. CMOS construction
eliminates wasted ground current, typical of bipolar
regulators, for greater system efficiencies and longer
operating time in battery-powered systems. The TC56
enters shutdown mode when the shutdown control
input (SHDN) is low. During shutdown, the regulator is
shut off, and supply current falls to 0.1
A maximum.
Normal operation is restored when SHDN is returned to
a logic high. Low current consumption, 10V supply
tolerance and space-saving 5-Pin SOT-23A packaging
makes the TC56 ideal for a wide variety of applications.
Functional Block Diagram
Part Number
Output
Voltage
(V)*
Package
Temperature
Range
TC562502ECT
2.5
5-Pin SOT-23A -40C to +85C
TC563002ECT
3.0
5-Pin SOT-23A -40C to +85C
TC563302ECT
3.3
5-Pin SOT-23A -40C to +85C
5
V
OUT
V
SS
SHDN
5-Pin SOT-23A
TC56
1
3
4
NC
2
V
IN
TC56
5
4
1
2
3
10
F
Tantalum
V
OUT
(NC)
V
SS
V
IN
SHDN
V
OUT
ON OFF Shutdown
Control
4.7
F
Tantalum
V
IN
150mA, 10V LDO with Shutdown
TC56
DS21436B-page 2
2002 Microchip Technology Inc.
1.0
ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings*
Input Voltage ........................................................+12V
Output Current ..................................................500mA
Output Voltage.......................V
SS
0.3V to V
IN
+ 0.3V
SHDN Input Voltage ..............V
SS
0.3V to V
IN
+ 0.3V
Power Dissipation (SOT-23).............................150mW
Operating Temperature Range............. -40C to +85C
Storage Temperature Range ..............-40C to +125C
*Stresses above those listed under "Absolute Maximum
Ratings" may cause permanent damage to the device. These
are stress ratings only and functional operation of the device
at these or any other conditions above those indicated in the
operation sections of the specifications is not implied.
Exposure to Absolute Maximum Rating conditions for
extended periods may affect device reliability.
TC56 ELECTRICAL SPECIFICATIONS
Electrical Characteristics: V
IN
= V
OUT
+1V, T
A
= 25C, C
IN
= 4.7
F, C
OUT
= 10
F, unless otherwise noted.
Symbol
Parameter
Min
Typ
Max
Units
Test Conditions
V
IN
Input Voltage
--
--
10
V
V
OUT
Output Voltage
0.98 x V
R
V
R
0.5% 1.02 x V
R
V
I
OUT
= 40mA (Note 1)
I
OUT
MAX
Maximum Output Current
150
180
--
--
--
--
mA
V
R
2.7V, V
OUT
= 3V (Note 1)
V
R
4.5V, V
OUT
= 5V (Note 1)
V
OUT
Load Regulation
--
--
45
40
90
80
mV
1mA
I
OUT
80mA, V
OUT
= 3V
1mA
I
OUT
80mA, V
OUT
= 5V
V
IN
- V
OUT
Dropout Voltage
--
--
--
--
200
380
165
330
395
770
330
660
mV
I
OUT
= 80mA, V
OUT
= 3V
I
OUT
= 160mA, V
OUT
= 3V
I
OUT
= 100mA, V
OUT
= 5V
I
OUT
= 200mA, V
OUT
= 5V (Note 2)
I
DD
Supply Current
--
--
11
13
19
21
A
V
SHDN
= V
IN
= 4V
V
SHDN
= V
IN
= 6V
I
SHDN
Shutdown Supply Current
--
--
0.1
A
V
SHDN
= GND
V
OUT
/
V
IN
Line Regulation
--
0.2
0.3
%/V
I
OUT
= 40mA, 4V
V
IN
10V
V
OUT
/
T
V
OUT
Temperature Coefficient
--
100
--
ppm/C
I
OUT
= 10mA, -40C < T
J
< +
85C
V
IH
SHDN Input High Logic Threshold
1.5
--
--
V
V
IL
SHDN Input Low Logic Threshold
--
--
0.25
V
I
IH
SHDN Input Current @V
IH
--
--
5.0
A
V
SHDN
= V
IN
I
IL
SHDN Input Current @V
IL
-0.2
-0.05
0
A
V
SHDN
= GND
Note 1:
V
R
is the regulator output voltage setting.
2:
Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at a
1V differential.
2002 Microchip Technology Inc.
DS21436B-page 3
TC56
2.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 2-1.
TABLE 2-1:
PIN FUNCTION TABLE
3.0
DETAILED DESCRIPTION
The TC56 is a precision, fixed output LDO. Unlike
bipolar regulations, the TC56 supply current does not
increase with load current.
3.1
Output Capacitor
A 10
F tantalum capacitor from V
OUT
to ground is
recommended. The output capacitor should have an
effective series resistance greater than 0.1
and less
than 5.0
, and a resonant frequency above 1MHz. It is
recommended that a 4.7
F capacitor be connected
from V
IN
to GND. 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
Shutdown Input
The TC56 enters a low power shutdown mode when
the shutdown control input (SHDN) is low. During
shutdown, the regulator is disabled and supply current
is reduced to 0.1
A (max). Normal operation is
restored when SHDN is driven high. If not required, the
SHDN input can be tied to V
IN
.
Pin No.
(5-Pin SOT-23A)
Symbol
Description
1
V
SS
Ground.
2
V
IN
Supply voltage input.
3
SHDN
Shutdown input.
4
(NC)
No connection.
5
V
OUT
Regulated voltage output.
TC56
DS21436B-page 4
2002 Microchip Technology Inc.
4.0
THERMAL CONSIDERATIONS
4.1
Power Dissipation
The amount of power the regulator dissipates is
primarily a function of input and output voltage, and
output current. The following equation is used to
calculate worst case actual power dissipation.
EQUATION 4-1:
The maximum allowable power dissipation
(Equation 4-2) is a function of the maximum ambient
temperature (T
A
MAX
), the maximum allowable die
temperature (T
J
MAX
) and the thermal resistance from
junction-to-air (
JA
). The 5-Pin SOT-23A package has
a
JA
of approximately 220C/Watt.
EQUATION 4-2:
Equation 4-1 can be used in conjunction with
Equation 4-2 to ensure regulator thermal operation is
within limits. For example:
Given:
V
IN
MAX
= 3.0V 10%
V
OUT
MIN
= 2.7V 2%
I
LOAD
MAX
= 98mA
T
J
MAX
= 125C
T
A
MAX
= 55C
Find: 1. Actual power dissipation
2. Maximum allowable dissipation
Actual power dissipation:
P
D
(V
IN
MAX
V
OUT
MIN
)I
LOAD
MAX
= [(3.0 x 1.1) (2.7 x .98)]98 x 10
-3
= 64mW
Maximum allowable power dissipation:
In this example, the TC56 dissipates a maximum of
64mW; below the allowable limit of 318mW. In a similar
manner, Equation 4-1 and Equation 4-2 can be used to
calculate maximum current and/or input voltage limits.
4.2
Layout Considerations
The primary path of heat conduction out of the package
is via the package leads. Therefore, layouts having a
ground plane, wide traces at the pads, and wide power
supply bus lines combine to lower
JA
and therefore,
increase the maximum allowable power dissipation
limit.
Where:
P
D
(V
IN
MAX
V
OUT
MIN
)I
LOAD
MAX
P
D
V
IN
MAX
V
OUT
MIN
I
LOAD
MAX
= Worst case actual power dissipation
= Minimum regulator output voltage
= Maximum output (load) current
= Maximum voltage on V
IN
P
D
MAX
= (T
J
MAX
T
A
MAX
)
JA
Where all terms are previously defined.
P
D
MAX
= (T
J
MAX
T
A
MAX
)
JA
= (125 55)
220
= 318mW
2002 Microchip Technology Inc.
DS21436B-page 5
TC56
5.0
TYPICAL CHARACTERISTICS
Note:
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein are
not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
0
20 40 60
100
140
OUTPUT CURRENT I
OUT
(mA)
0
40
80
120 140
180
OUTPUT CURRENT I
OUT
(mA)
OU
TP
U
T V
O
LTA
G
E V
OU
T
(
V
)
TC563002 (3V)
5.1
OUTPUT VOLTAGE V
OUT
(V)
TC565002 (5V)
4.7
4.8
4.9
5.0
20
60
100
160
T
O
OPR
= 25
C
80
C
-30
C
V
IN
= 6V
C
IN
= 4.7
F, C
L
= 10
F (Tantalum)
2.7
2.8
2.9
3.0
3.1
80
120
160 180
T
OPR
= 25
C
C
-30
C
80
C
C
1. OUTPUT VOLTAGE vs. OUTPUT CURRENT
V
IN
= 4V
C
IN
= 4.7
F, C
L
= 10
2.5
3.0
3.5
OUTPUT VOLTAGE V
OUT
(V)
TC563002 (3V)
O
UTPUT VOLTAGE V
O
UT
(
V
)
5
6
7
10
INPUT VOLTAGE V
IN
(V)
TC565002 (5V)
4.8
4.6
4.4
4.2
4.5
5.5
INPUT VOLTAGE V
IN
(V)
INPUT VOLTAGE V
IN
(V)
INPUT VOLTAGE V
IN
(V)
TC565002 (5V)
5.0
5.2
OUTPUT VOLTAGE V
OU
T
(
V
)
3.05
2.85
3
5
7
10
OU
TP
U
T V
O
LTA
G
E V
OU
T
(
V
)
TC563002 (3V)
2.95
3.10
5
8
9
4.85
4.90
4.95
5.00
5.05
5.10
40mA
2.2
2.4
2.6
2.8
3.0
3.2
3.00
2.90
4
6
8
9
40mA
I
OUT
A
A
= 1mA
10mA
10mA
40mA
I
OUT
= 1mA
I
OUT
A
A
= 1mA
I
OUT
mA
= 1mA, 10m
2. OUTPUT VOLTAGE vs. INPUT VOLTAGE
40mA
T
OPR
= 25
C
C
IN
= 4.7
F, C
L
= 10
F (Tantalum)
T
OPR
= 25
C
C
IN
= 4.7
F, C
L
T
OPR
= 25
C
C
IN
= 4.7
F, C
L
T
OPR
= 25
C
C
IN
= 4.7
F, C
L
= 10
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