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
available. In addition, the output voltage of every device
can be adjusted between 1.2V and 4.8V using external
resistors. The SC1563 comes in both 5-pin
SOT-23 and 8-pin MSOP packages to allow the user to
select a package suitable for their spacing and heat
dissipation needs.
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
SOT-23-5 and MSOP-8 surface mount packages
Applications
Personal Digital Assistants
Battery powered systems
Motherboards
Peripheral cards
PCMCIA cards
Externally Set Output Voltage
Typical Application Circuits
Internally Preset Output Voltage
U1
VIN
SHDN
5
1
IN
SC1563IS-X.X
OUT
4
VO (X.XV)
U1
VIN
SHDN
5
1
IN
SC1563IS-X.X
OUT
4
R1
VO
SHDN GND ADJ
2
3
C2
SHDN GND ADJ
2
3
C1
C1
C2
R2
VIN
SHDN
VO (X.XV)
U1 SC1563IMS-X.X
8
IN
GND
2
7
SHDN
GND
3
6
ADJ
GND
4
5
OUT
GND
1
VIN
SHDN
R1
VO
R2
U1 SC1563IMS-X.X
8
IN
GND
2
7
SHDN
GND
3
6
ADJ
GND
4
5
OUT
GND
1
C1
C2
C1
C2
V
OUT
=
1.200 (R1
+
R2)
Volts
R2
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Revision: October 14, 2004
1
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
MSOP-8
(1)
MSOP-8
(2)
SOT-23-5
(1)
Thermal Resistance Junction to Case
MSOP-8
SOT-23-5
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
Maximum
-0.3 to 7
-0.3 to V
IN
Internally Limited
206
95
256
39
81
-40 to 85
-40 to 150
-65 to 150
300
2
Units
V
V
W
°C/W
θ
J C
T
A
T
J
T
STG
T
LEAD
V
ESD
°C/W
°C
°C
°C
°C
kV
Notes:
(1) Minimum pad size.
(2) 1 square inch of FR-4, double sided, 1oz. minimum copper weight.
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)
SC1563IMS-X.XTR
SC1563IMS-X.XTRT
(4)
SC1563ISK-X.XTR
SC1563ISK-X.XTRT
(4)
SOT-23-5
P ackag e
MSOP-8
SOT-23-5
MSOP-8
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 2500 devices (MSOP-8) or 3000 devices
(SOT-23-5).
(4) Lead free product. This product is fully WEEE and RoHS
compliant.
Marking Information
MSOP-8
SOT-23-5
63XX = SC1563, voltage option (example: 6318 for 1.8V option)
yyww = Date code (example: 0008 for week 8 of 2000)
XXXXXXXX = Lot number, not marked on SOT-23-5 (example: E01102)
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SC1563
POWER MANAGEMENT
Block Diagram
Pin Descriptions
Pin
Name
AD J
Pin Number
MSOP-8
3
SOT-23-5
3
Thi s pi n, when grounded, sets the output voltage to that set by the i nternal feedback
resistors. 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
Pin Function
GND
IN
OUT
SHDN
5-8
1
4
2
2
5
4
1
Reference ground. C onnect all MSOP-8 pi ns. These pi ns may be used for heatsi nki ng
purposes.
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.
This pin is the power output of this device, sourcing up to 500mA.
Shutdown Input. Leaving this pin open turns the regulator off, reducing the quiescent 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.
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