Very Low Dropout
1.5 Amp Regulator With Enable
POWER MANAGEMENT
Description
The SC1565 is a high performance positive voltage
regulator designed for use in applications requiring very
low dropout voltage at up to 1.5 Amps. Since it has
superior 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 thus
allowing the elimination of costly heatsinks. Additionally,
the 5-lead TO-220/TO-263 and SO-8 versions have an
enable pin to further reduce power dissipation while shut
down. The SC1565 provides excellent regulation over
variations in line, load and temperature.
The SC1565 is available in SO-8, 3-lead SOT-223, 3 and
5 lead TO-220 and 3 and 5 lead TO-263 packages. Three
lead packages are available with 1.8V and 2.5V fixed
output options only. The SO-8, TO-220-5 and TO-263-5
are available with 1.8V and 2.5V internally preset
outputs that are also adjustable using external resistors.
SC1565
Features
350mV dropout @ 1.5A
Adjustable output from 1.2V to 4.8V
(1)
2.5V and 1.8V options (adjustable externally
using resistors)
(1)
Over current and over temperature protection
Enable pin
(1)
10µA quiescent current in shutdown
(1)
Low reverse leakage (output to input)
Surface mount and through-hole packages
Full industrial temperature range
TO-220, TO-263, SOT-223 and SO-8 Packages
Note:
(1) SO-8, TO-220-5 and TO-263-5 packages only.
Applications
Battery powered systems
Motherboards
Peripheral cards
Network cards
Set Top Boxes
Medical Equipment
Notebook Computers
Typical Application Circuits
U1
ENABLE
VIN
VO
1
2
3
4
R1
EN
VIN
VO
ADJ
GND
GND
GND
GND
8
7
6
5
ENABLE
VIN
VO
U1
1
2
3
4
C1
C1
C2
R2
C2
EN
VIN
VO
ADJ
GND
GND
GND
GND
8
7
6
5
SC1565IS-X.X
SC1565IS-X.X
VO
=
1.200 (R1
+
R2)
R2
Volts
U1
SC1565I5T-X.X
VIN
ENABLE
2
1
VIN
EN
VO
GND ADJ
3
C1
C2
R2
4
5
VO
=
1.200 (R1
+
R2)
R2
Volts
VO
U1
SC1565IT-X.X
VIN
1
VIN
GND
C1
2
C2
VO
3
VO
R1
Notes:
(1) Maximum VO setpoint for 1.8V parts = 5.4V.
(2) This device is designed to operate with ceramic input and output capacitors.
Revision: April 27, 2005
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SC1565
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
Power Dissipation
Thermal Resistance Junction to Ambient
SO-8
(1)
SOT-223
TO-220-X
TO-263-X
Thermal Resistance Junction to Case
SO-8
SOT-223
TO-220-X, TO-263-X
Operating Ambient Temperature Range
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering) 10 Sec.
ESD Rating (Human Body Model)
Note:
(1) 1 square inch of FR-4, double sided, 1 oz. minimum copper weight.
Symbol
V
IN
P
D
θ
J A
Max
7
Internally Limited
65
63
50
60
39
27
3
-40 to +85
-40 to +150
-65 to +150
300
4
Units
V
W
°C/W
θ
J C
°C/W
T
A
T
J
T
STG
T
LEAD
V
ESD
°C
°C
°C
°C
kV
Electrical Characteristics
Unless specified: V
EN
= V
IN
. Adjustable Option (V
ADJ
> V
TH(ADJ)
): V
IN
= 2.2V to 5.5V and I
O
= 10µA to 1.5A.
Fixed Options (V
ADJ
= GND): V
IN
= (V
O
+ 0.7V) to 5.5V and I
O
= 0A to 1.5A. Values in
bold
apply over the full operating temperature range.
Parameter
VIN
Supply Voltage Range
Quiescent Current
Symbol
Test Conditions
Min
Typ
Max
Units
V
IN
I
Q
V
IN
= 3.3V
V
IN
= 5.5V, V
EN
= 0V
2.2
0.75
10
5.5
1.75
35
V
mA
µA
VO
Output Voltage
(1)
(Internal Fixed Voltage)
Line Regulation
(1)
Load Regulation
(1)
Dropout Voltage
(1)(2)
REG
(LINE)
REG
(LOAD)
V
D
V
IN
= (V
O
+ 0.25V) to 5.5V, I
OUT
= 10mA
V
IN
= V
O
+ 0.7V
I
O
= 10mA
V
O
V
IN
= V
O
+ 0.7V, I
O
= 10mA
-1%
-2%
0.035
0.2
2.5
V
O
+1%
+2%
0.3
0.4
10
20
I
O
= 500mA
90
300
400
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V
%
%
mV
mV
SC1565
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: V
EN
= V
IN
. Adjustable Option (V
ADJ
> V
TH(ADJ)
): V
IN
= 2.2V to 5.5V and I
O
= 10µA to 1.5A.
Fixed Options (V
ADJ
= GND): V
IN
= (V
O
+ 0.7V) to 5.5V and I
O
= 0A to 1.5A. Values in
bold
apply over the full operating temperature range.
Parameter
VO (Cont.)
Dropout Voltage
(1)(2)
Symbol
Test Conditions
Min
Typ
Max
Units
I
O
= 1A
180
400
500
mV
I
O
= 1.5A
270
500
600
mV
Minimum Load Current
(3)
Current Limit
ADJ
Reference Voltage
(1)
I
O
I
CL
V
IN
= V
O
+ 0.7V
1.6
1
2.0
10
3.5
µA
A
V
REF
V
IN
= 2.2V, V
ADJ
= V
OUT
, I
O
= 10mA
1.188
1.176
1.200
1.212
1.224
V
Adjust Pin Current
(4)
Adjust Pin Threshold
(5)
EN
Enable Pin Current
Enable Pin Threshold
I
ADJ
V
TH(ADJ)
V
ADJ
= V
REF
0.05
30
0.20
200
0.40
nA
V
I
EN
V
IH
V
IL
V
EN
= 0V, V
IN
= 3.3V
V
IN
= 3.3V
V
IN
= 3.3V
1.6
1.5
10
µA
V
0.4
Over Temperature Protection
High Trip level
Hysteresis
T
HI
T
HYST
170
20
°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.
(3) Required to maintain regulation. Voltage set resistors R1 and R2 are usually utilized to meet this
requirement. Adjustable versions only.
(4) Guaranteed by design.
(5) 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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SC1565
POWER MANAGEMENT
Pin Configurations
Ordering Information
Device
SC1565IS-X.XTR
(1)(3)
SC1565IS-X.XTRT
(1)(3(6)
SC1565IST-X.XTR
(2)(3)
SC1565IST-XXTRT
(2)(3)(6)
P ackag e
SO-8
SOT-223
SO-8
SC1565IM-X.XTR
(2)(4)
SC1565IM-XXTRT
(2)(4)(6)
TO-263-3
SC1565I5M-X.XTR
(1)(4)
SC1565I5MX.XTRT
(1)(4)(6)
TO-263-5
SC1565IT-X.X
(2)(5)
SC1565IT-X.XT
(2)(5)(6)
SC1565I5T-X.X
(1)(5)
TO-220-3
SOT-223
SC1565I5T-X.XT
(1)(5)(6)
TO-220-5
TO-220-3
SOT-223, TO-220-3
and TO-263-3
PIN
1
2
3
FUNCTION
VIN
GND
VO
TAB is GND
TO-220-5
TO-220-5 and TO-263-5
PIN
1
2
3
4
5
FUNCTION
EN
VIN
GND
VO
AD J
TAB is GND
Notes:
(1) Where -X.X denotes voltage options. Available
voltages are: 2.5V and 1.8V. Output voltage can be
adjusted using external resistors, see Pin Descriptions
on page 5.
(2) Where -X.X denotes voltage options. Available
voltages are: 2.5V and 1.8V. Output not adjustable.
(3) Only available in tape and reel packaging. A reel
contains 2500 devices.
(4) Only available in tape and reel packaging. A reel
contains 800 devices.
(5) Only available in tube packaging. A tube contains 50
devices.
(6) Lead free product. This product is fully WEEE and
RoHS compliant.
Pin Configurations (Cont.)
TO-263-3
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TO-263-5
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SC1565
POWER MANAGEMENT
Block Diagram
*
*
* Not present on SOT-223, TO-220-3 or TO-263-3
Pin Descriptions
Pin Name Pin Desciption
AD J
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 Circuits on page 1):
VO
=
1.200 (R1
+
R2)
R2
Volts
EN
GND
VIN
VO
Enable Input. Pulling this pin below 0.4V turns the regulator off, reducing the quiescent current to a fraction of
its operating value. The device will be enabled if this pin is left open. Connect to VIN if not being used.
Reference ground. Use all four pins on the SO-8 device for heatsinking. Use the tab on the SOT-223, TO-220
and TO-263 devices for heatsinking.
Input voltage. For regulation at full load, the input to this pin must be between (VO + 0.7V) and 5.5V. Minimum
VIN = 2.2V.
The pin is the power output of the device.
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