Very Low Dropout, Low
Quiescent 500mA Regulator
POWER MANAGEMENT
Description
The SC1563 is a high performance positive voltage
regulator designed for use in applications requiring very
low dropout voltage at up to 500mA. Since it has supe-
rior dropout characteristics compared to regular LDOs, it
can be used to supply 2.5V on motherboards or 2.8V on
peripheral cards from the 3.3V supply with no heatsink.
Additionally, the SC1563 has a shutdown pin to further
reduce power dissipation while shut down. The SC1563
provides excellent regulation over variations in line, load
and temperature.
A wide range of fixed output voltage options are avail-
able. In addition, the output voltage of every device can
be adjusted between 1.2V and 4.8V using external resis-
tors. The SC1563 comes in the space saving 5-pin SOT-
23 package.
SC1563
Features
350mV dropout @ 500mA
Designed to operate with ceramic capacitors
Adjustable output from 1.2V to 4.8V
Multiple output voltage options (all parts also
adjustable externally using resistors)
Over current and over temperature protection
2µA quiescent current in shutdown
No minimum load current requirement
Low reverse leakage (output to input)
Full industrial temperature range
5-pin SOT-23 surface mount package. Also avail-
able in Lead-free, fully WEEE and RoHS compliant
Applications
Personal Digital Assistants
Battery powered systems
Motherboards
Peripheral cards
PCMCIA cards
Typical Application Circuits
Internally Preset Output Voltage
Externally Set Output Voltage
U1
VIN
SHDN
5
1
IN
SC1563IS-X.X
OUT
4
VO (X.XV)
VIN
SHDN
C2
C1
5
1
U1
IN
SC1563IS-X.X
OUT
4
R1
VO
SHDN GND ADJ
2
3
SHDN GND ADJ
2
3
C1
C2
R2
V
OUT
=
1.200 (R1
+
R2)
Volts
R2
Revision: January 11, 2006
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SC1563
POWER MANAGEMENT
Absolute Maximum Ratings
Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters
specified in the Electrical Characteristics section is not implied.
Parameter
Input Voltage
Shutdown Voltage
Power Dissipation
Thermal Resistance Junction to Ambient
(1)
Operating Ambient Temperature Range
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering) 10 sec
ESD Rating
Symbol
V
IN
V
SHDN
P
D
θ
JA
T
A
T
J
T
STG
T
LEAD
V
ESD
Maximum
-0.3 to 7
-0.3 to V
IN
Internally Limited
175
-40 to 85
-40 to 150
-65 to 150
300
2
Units
V
V
W
°C/W
°C
°C
°C
°C
kV
Note:
(1) Minimum pad size.
Electrical Characteristics
Unless specified: V
SHDN
= 0V, Adjustable mode (V
ADJ
> V
TH(ADJ)
): V
IN
= 2.2V to 5.5V and I
OUT
= 0A to 500mA,
Fixed mode (V
ADJ
= GND): V
IN
= (V
OUT
+ 0.7V) to 5.5V and I
OUT
= 0A to 500mA. Values in
bold
apply over full operating temperature range.
Parameter
IN
Supply Voltage Range
Quiescent Current
Symbol
Conditions
Min
Typ
Max
Units
V
IN
I
Q
V
IN
= 3.3V
V
IN
= 6.5V, V
SHDN
= Open
2.2
85
0.01
6.5
150
2.00
V
µA
µA
OUT
Output Voltage
(1)
(Internal Fixed Voltage)
Line Regulation
(1)
Load Regulation
(1)
REG
(LINE)
REG
(LOAD)
V
IN
= (V
OUT
+ 0.25V) to 5.5V, I
OUT
= 10mA
V
IN
= V
OUT
+ 0.7V
V
OUT
V
IN
= V
OUT
+ 0.7V, I
OUT
= 10mA
-1%
-2%
0.1
0.15
V
OUT
+1%
+2%
0.4
0.40
%
%
V
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SC1563
POWER MANAGEMENT
Electrical Characteristics
Unless specified: V
SHDN
= 0V, Adjustable mode (V
ADJ
> V
TH(ADJ)
): V
IN
= 2.2V to 5.5V and I
OUT
= 0A to 500mA,
Fixed mode (V
ADJ
= GND): V
IN
= (V
OUT
+ 0.7V) to 5.5V and I
OUT
= 0A to 500mA. Values in
bold
apply over full operating temperature range.
Parameter
OUT (Cont.)
Dropout Voltage
(1)(2)
Symbol
Conditions
Min
Typ
Max
Units
V
D
I
OUT
= 2mA
1
5
10
mV
I
OUT
= 100mA
70
100
150
mV
I
OUT
= 250mA
175
250
350
mV
I
OUT
= 500mA
350
500
700
mV
Current Limit
ADJ
Reference Voltage
(1)
I
LIM
0.5
1.0
A
V
REF
V
IN
= 2.2V, V
ADJ
= V
OUT
, I
OUT
= 10mA
1.188
1.176
1.200
1.212
1.224
V
Adjust Pin Current
(3)
Adjust Pin Threshold
(4)
SH D N
Shutdown Pin Current
Shutdown Pin Threshold
I
ADJ
V
TH(ADJ)
V
ADJ
= V
REF
0.10
65
0.25
150
0.40
nA
V
I
SHDN
V
IH
V
IL
V
SHDN
= 0V, V
IN
= 3.3V
V
IN
= 3.3V
V
IN
= 3.3V
1.8
1.5
5.0
µA
V
0.4
Over Temperature Protection
High Trip Level
Hysteresis
T
HI
T
HYST
170
10
°C
°C
Notes:
(1) Low duty cycle pulse testing with Kelvin connections required.
(2) Defined as the input to output differential at which the output voltage drops to 1% below the value measured at
a differential of 0.7V for 2.5V
≤
V
OUT
≤
3.4V. Not measurable on outputs less than 2.2V due to minimum V
IN
con-
straints. See typical characteristics curves.
(3) Guaranteed by design.
(4) When V
ADJ
exceeds this threshold, the “Sense Select” switch disconnects the internal feedback chain from the
error amplifier and connects V
ADJ
instead.
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SC1563
POWER MANAGEMENT
Pin Configurations
Top View
Ordering Information
Part Number
(1)(2)(3)
SC1563ISK-X.XTR
SC1563ISK-X.XTRT
(4)
SOT-23-5
P ackag e
SOT-23-5
Notes:
(1) Where -X.X denotes voltage options. Available
voltages are: 1.8V, 2.5V, 2.8V, 3.0V, 3.1V and 3.3V.
(2) Output voltage can be adjusted using external
resistors, see Pin Descriptions.
(3) Only available in tape and reel packaging. A reel
contains 3000 devices.
(4) Lead free product. This product is fully WEEE and RoHS
compliant.
Marking Information
SOT-23-5
63XX = SC1563, voltage option (example: 6318 for 1.8V option)
yyww = Date code (example: 0008 for week 8 of 2000)
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SC1563
POWER MANAGEMENT
Block Diagram
Pin Descriptions
Pin #
1
Pin Name Pin Function
SHDN
Shutdown Input. Leavi ng thi s pi n open turns the regulator off, reduci ng the qui escent current to a
fraction of its operating value (typically < 300nA). The device will be enabled if this pin is pulled below
0.4V. Connect to GND if not being used.
Reference ground. This pin may be used for heatsinking purposes.
Thi s pi n, when grounded, sets the output voltage to that set by the i nternal feedback resi stors. If
external feedback resistors are used, the output voltage will be (See Application Circuit on page 1):
V
OUT
=
1.200 (R1
+
R2)
Volts
R2
2
3
GND
AD J
4
5
OUT
IN
This pin is the power output of this device, sourcing up to 500mA.
Input voltage. For regulation at full load, the input to this pin must be between (V
OUT
+ 0.7V) and 6.5V.
Minimum V
IN
= 2.2V.
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