Datasheet SC1563IMS-1.8TR, SC1563IMS-2.5TR, SC1563IMS-2.8TR, SC1563IMS-3.0TR, SC1563IMS-3.1TR Datasheet (Semtech Corporation)

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

1

FEATURES

•= 450mV dropout @ 500mA

•= Designed to operate with ceramic capacitors

•= Adjustable output from 1.200V to 3.3V

•= Multiple output voltage options (all parts also

adjustable externally using resistors)

•= Over current and over temperature protection

•= Enable pin

•= 1µA quiescent current in shutdown

•= Low reverse leakage (output to input)

•= Full industrial temperature range

DESCRIPTION

The SC1563 is a high performance positive voltage
regulator designed for use in applications requiring
very low dropout voltage at up to 500 milliamps. 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 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.

The SC1563 is available as a five terminal fixed or
adjustable output voltage device with enable. The
device is available in a 5-pin SOT-23 package and an
8-pin MSOP package for higher power dissipation/
lower junction temperature.

APPLICATIONS

•= Battery powered systems

•= Motherboards

•= Peripheral cards

•= PCMCIA cards

DEVICE

(1)(2)(3)

PACKAGE

SC1563ISK-X.XTR SOT-23-5L
SC1563IMS-X.XTR MSOP-8

ORDERING INFORMATION

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 Description.
(3) Only available in tape and reel packaging. A reel
contains 2500 devices (MSOP-8) or 3000 devices
(SOT-23-5L).

TEL:[phone] FAX:[phone] WEB:http://www.semtech.com

TYPICAL APPLICATION

Internally Preset Output Voltage Externally Set Output Voltage

Volts

R2

R2)(R11.200VO+

=

VIN

SHDN

VO (X.XV)

VIN

SHDN

VO

U1 SC1563ISK-X.X

1

2 3

45

SHDN

GND ADJ

VOVIN

C1

C2

U1 SC1563ISK-X.X

1

2 3

45

SHDN

GND ADJ

VOVIN

C1

C2

R1

R2

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

2

ABSOLUTE MAXIMUM RATINGS

Parameter Symbol Maximum Units

Input Voltage V

IN

5.5 V

Power Dissipation P

D

Internally Limited W

Thermal Resistance Junction to Ambient
MSOP-8

(1)

MSOP-8

(2)

SOT-23-5L

(1)

θ

JA

206

95

256

°C/W

Thermal Resistance Junction to Case
MSOP-8
SOT-23-5L

θ

JC

39
81

°C/W

Operating Ambient Temperature Range

T

A

-40 to+85 °C

Operating Junction Temperature Range T

J

-40 to 150 °C

Storage Temperature Range T

STG

-65 to 150 °C

Lead Temperature (Soldering) 10 Sec. T

LEAD

300 °C

ESD Rating ESD 2 kV

ELECTRICAL CHARACTERISTICS

Unless specified: V

SHDN

= 0V

Adjustable Option (V

ADJ

> V

TH(ADJ)

): VIN = 2.2 to 5.5V and IO = 10µA to 500mA

Fixed Options (V

ADJ

= GND): VIN = (VO + 0.7V) to 5.5V and IO = 0A to 500mA

Values in bold apply over the full operating temperature range.

Parameter Symbol Test Conditions Min Typ Max Units
VIN

Supply Voltage Range VIN

2.2 5.5

V

Quiescent Current I

Q

VIN = 3.3V 100

150

µA

V

IN

= 5.5V, V

SHDN

= Open 0.5

2

µA

VO

Output Voltage

(1)

V

O

VIN = VO + 0.7V, IO = 10mA 0.99V

O

V

O

1.01V

O

V

(Internal Fixed Voltage)

0.98V

O

V

O

1.02V

O

Line Regulation

(1)

REG

(LINE)VIN

= (VO + 0.25V) to 5.5V, I

OUT

= 10mA 0.035

0.3

%

Load Regulation

(1)

REG

(LOAD)

VIN = VO + 0.7V 0.2

0.4

%

Notes:
(1) Minimum pad size.
(2) 1 square inch of FR-4, double sided, 1oz. minimum copper weight.

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

3

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.

ELECTRICAL CHARACTERISTICS (Cont.)

Unless specified: V

SHDN

= 0V

Adjustable Option (V

ADJ

> V

TH(ADJ)

): VIN = 2.2 to 5.5V and IO = 10µA to 500mA

Fixed Options (V

ADJ

= GND): VIN = (VO + 0.7V) to 5.5V and IO = 0A to 500mA

Values in bold apply over the full operating temperature range.

Parameter Symbol Test Conditions Min Typ Max Units
VO (Cont.)

Dropout Voltage

(2)

V

D

I

LOAD

= 2mA 1 5 mV

10

I

LOAD

= 100mA 75 100 mV

150

I

LOAD

= 250mA 200 300 mV

400

I

LOAD

= 500mA 450 550 mV

700

Minimum Load Current

(3)

I

O

VIN = VO + 0.7V 1

10

µA

Current Limit I

CL

0.50 1.00

A

ADJ

Reference Voltage

(1)

V

REF

VIN = 2.2V, V

ADJ

= V

OUT

, IO = 10mA 1.188 1.200 1.212 V

1.176 1.224

Adjust Pin Current

(4)

I

ADJ

V

ADJ

= V

REF

50

100

nA

Adjust Pin Threshold

(5)

V

TH(ADJ)

0.10

0.20

0.40

V

SHDN

Shutdown Pin Current I

SHDN

V

SHDN

= 0V, VIN = 3.3V 1

10

µA

Shutdown Pin Threshold V

IH

V

IN

= 3.3V

1.8

V

V

IL

V

IN

= 3.3V

0.4

OVER TEMPERATURE PROTECTION

High Trip Level T

HI

165 °C

Hysteresis T

HYST

10 °C

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

4

PIN DESCRIPTION

Pin Pin Number Pin Function

Name SOT-23-5L MSOP-8

ADJ 3 3 This pin, when grounded, sets the output voltage to that set by the internal feed-

back resistors. If external feedback resistors are used, the output voltage will be
(See Application Circuit):

GND 2 5-8 Reference ground. Connect all MSOP-8 GND pins. These pins may be used for

heatsinking purposes.

VIN 5 1 Input voltage. For regulation at full load, the input to this pin must be between (VO

+ 0.7V) to 5.5V. Minimum VIN = 2.2V.

VO 4 4 This pin is the power output of this device.

SHDN 1 2 Shutdown Input. Leaving this pin open turns the regulator off, reducing the quies-

cent current to a fraction of its operating value (typically <100nA). The device will
be enabled if this pin is pulled below 0.4V. Connect to GND if not being used.

Volts

R2

R2)(R11.200VO+

=

BLOCK DIAGRAM

PIN CONFIGURATIONS

Top View

SOT-23-5L

Top View

MSOP-8

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

5

TYPICAL APPLICATION (Externally Set Output Voltage)

(1)(2)

Volts

R2

R2)(R1 1.200

VO+=

Notes:
(1) Maximum VO setpoint is 3.3V.
(2) This device is designed to operate with ceramic input and output capacitors.

TYPICAL APPLICATIONS (Internally Set Output Voltage)

(2)

VIN

SHDN

VO (X.XV)

U1

SC1563IS-X.X

1

2 3

4

5

SHDN

GND

ADJ

VOVIN

C1
1uF

C2
10uF

VIN

SHDN

VO

U1 SC1563IS-X.X

1

2 3

45

SHDN

GND

ADJ

VOVIN

C1
1uF

C2
10uF

R1

R2

VIN

VO (X.XV)

SHDN

U1

SC1563IMS-X.X

1
2
3
4

5

6

7

8

VIN
SHDN
ADJ
VO GND

GND

GND

GND

C1
1uF

C2
10uF

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

6

APPLICATIONS INFORMATION

Introduction

The SC1563 is intended for applications such as
graphics cards where high current capability and very
low dropout voltage are required. It provides a very
simple, low cost solution that uses little pcb real estate
and typically does not require a heatsink. Additional
features include an enable pin to allow for a very low
power consumption standby mode, and a fully ad­justable output.

Component Selection

Input capacitor - a 1µF ceramic capacitor is recom­mended. This allows for the device being some dis­tance from any bulk capacitance on the rail. Addition­ally, input droop due to load transients is reduced, im­proving load transient response. Additional capaci­tance may be added if required by the application.

Output capacitor - a minimum bulk capacitance of 1µF,
along with a 0.1µF ceramic decoupling capacitor is rec­ommended. Increasing the bulk capacitance will im­prove the overall transient response. The use of multi­ple lower value ceramic capacitors in parallel to
achieve the desired bulk capacitance will not cause
stability issues. Although designed for use with ce­ramic output capacitors, the SC1563 is extremely toler­ant of output capacitor ESR values and thus will also
work comfortably with tantalum output capacitors.

External voltage selection resistors - the use of 1% re­sistors, and designing for a current flow ≥ 10µA is rec­ommended to ensure a well regulated output (thus R2
≤ 120kΩ).

Thermal Considerations

The power dissipation in the SC1563 is approximately
equal to the product of the output current and the input
to output voltage differential:

The absolute worst-case dissipation is given by:

For a typical scenario, VIN = 3.3V ± 5%, VOUT = 2.5V
and I

O

= 500mA, therefore:

VIN

(MAX)

= 3.465V, VOUT

(MIN)

= 2.450V and

I

Q(MAX)

= 1.75mA,

Thus P

D(MAX)

= 0.514W.

Using this figure, and assuming T

A(MAX)

= 85°C, we can
calculate the maximum thermal impedance allowable
to maintain T

J

≤ 150°C:

This should be achievable using pcb copper area to aid
in conducting the heat away from the device. Internal
ground/power planes and air flow will also assist in re­moving heat. For higher ambient temperatures addi­tional board copper may be required. Use of the avail­able MSOP-8 package will allow operation at full load
where higher input to output voltage differentials exist.

()

OD

IVOUTVINP •−≈

(

)

)MAX(Q)MAX()MAX(O)MIN()MAX()MAX(D

IVINIVOUTVINP •+•−=

(

)

()

W/C156

514.0

70150

P

TT

R

)MAX(D

)MAX(A)MAX(J

)MAX)(AJ(TH

°=

−

=

−

=

−

MARKING INFORMATION

MSOP-8

SOT-23-5L

63XX = SC1563, voltage option (example: 6318)
yyww = Datecode (example: 0008)
XXXX = Lot number (example: E01102)

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

7

DEVICE OUTLINE - SOT-23-5

LAND PATTERN - SOT-23-5

© 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320

VERY LOW DROPOUT, LOW
QUIESCENT 500mA REGULATOR

SC1563

PRELIMINARY - September 11, 2000

8

ECN00-1343

OUTLINE DRAWING - MSOP-8

LAND PATTERN - MSOP-8