Datasheet SC1150CS.TR Datasheet (Semtech Corporation)

SC1150

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

PROGRAMMABLE DC/DC
CONTROLLER

March 11, 1998

1

Pentium is a registered trademark of Intel Corporation

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

DESCRIPTION

The SC1150 voltage mode controller contains most of
the circuitry necessary to implement a DC/DC converter
for powering the Intel Pentium® Pro microprocessor,
both in single and multiple processor configurations.

The SC1150 features an integrated D/A converter,
pulse by pulse current limiting, integrated power good
signaling, logic compatible shutdown and on-board over
voltage protection (OVP).

The SC1150 operates at a fixed frequency of 200kHz,
providing an optimum compromise between size, effi­ciency and cost in the intended application areas.

The integrated D/A converter provides programmability
of output voltage from 2.0V to 3.5V in 100mV incre­ments with no external components. Both the range
and the increment value may be changed by adding ex­ternal components.

The SC1150 provides an OVP output which can be
used to trigger a crowbar circuit for true over voltage
protection.

FEATURES

• 85% efficiency

• 4 bit DAC for output programmability

• On chip power good and OVP functions

• Meets Intel Pentium

®

Pro VRM8.0 specifications

APPLICATIONS

• Pentium

®

Pro Processor supplies

• Pentium

®

Pro Processor VRM modules

• 2.0V to 3.5V microprocessor supplies

• Programmable power supplies

BLOCK DIAGRAM

VCC

VCC

1.00V to

1.75V

ERROR
AMP

OSCILLATOR

LEVEL SHIFT
AND DRIVE

1.25V REF

D/A

+

-

+

-

CURRENT LIMIT

+

-

+

-

CSm

VID0

VID2
VID1

VID3

VOSENSE

PWRGOOD

BST

DH

VCC

SHUTDOWN

OVP

GND FB

PGND

R

S

Q

+

-

70mV

CSp

+

-

B16997B

PIN CONFIGURATION

1
2
3
4
5
6
7
8

16
15
14
13
12
11
10

9

PWRGOOD

VID0
VID1
VID2
VID3

BSTDH

VOSENSE

GND

SHUTDOWNPGND

VCC

CSp

CSm

OVP

FB

ABSOLUTE MAXIMUM RATINGS

Parameter Symbol Maximum Units

VCC to GND V

IN

-0.3 to 7 V
PGND to GND ± 1 V
BST to GND -0.3 to 15 V
Operating

Temperature Range

T

A

0 to 70 °C

Storage
Temperature Range

T

STG

-65 to +150 °C

Lead Temperature
(Soldering) 10 sec

T

LEAD

300 °C

ORDERING INFORMATION

DEVICE

(1)

PACKAGE TEMP RANGE (TJ)

SC1150CS SO-16 0 - 125°C
Note:

(1) Add suffix ‘TR’ for tape and reel.

SC1150

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

PROGRAMMABLE DC/DC
CONTROLLER

March 11, 1998

2

NOTES:

(1) Low output currents, below the continuous conduction threshold will cause an increase in output voltage
beyond the load regulation limit. For Application circuit 16935E see the regulation curve on sheet 5.
(2) All VID codes not specifically listed here are invalid and cause shutdown exactly as if the shutdown pin had
been asserted. xxxx refers to any valid VID code.

ELECTRICAL CHARACTERISTICS

Unless specified: VCC = 4.75V to 5.25V; GND = PGND = 0V; V

OSENSE

= VO; 0mV < (CSp-CSm) < 60mV; TA = 25oC

PARAMETER CONDITIONS VID

3210

MIN TYP MAX UNITS

Output Voltage

(2)

IO = 2A in Application circuit 16935E 1111 1.980 2.000 2.020 V

1110 2.079 2.100 2.121
1101 2.178 2.200 2.222
1100 2.277 2.300 2.323
1011 2.376 2.400 2.424
1010 2.475 2.500 2.525
1001 2.574 2.600 2.626
1000 2.673 2.700 2.727
0111 2.772 2.800 2.828
0110 2.871 2.900 2.929
0101 2.970 3.000 3.030
0100 3.069 3.100 3.131
0011 3.168 3.200 3.232
0010 3.267 3.300 3.333
0001 3.366 3.400 3.434
0000 3.465 3.500 3.535

Load Regulation IO = 0.3A to 13A

(1)

xxxx 1 %
Line Regulation xxxx 0.5 %
UV Lockout xxxx 4.2 V
Current Limit Voltage xxxx 60 70 80 mV
Oscillator Frequency xxxx 180 200 220 kHz
Oscillator Max Duty

Cycle

xxxx 90 95 %

DH Sink/Source Current BST - DH = 4.5V, DH - PGND = 2V xxxx 1 A
Output Voltage Tempco xxxx 65 ppm/oC

SC1150

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

PROGRAMMABLE DC/DC
CONTROLLER

March 11, 1998

3

NOTE:

(1) All logic level inputs and outputs are open collector TTL compatible

PIN DESCRIPTION

Pin # Pin Name Pin Function

1

GND

Small Signal Analog and Digital Ground

2

V

CC

Chip Supply Voltage

3

OVP

(1)

High Signal out if VO>setpoint + 20%

4

PWRGOOD

(1)

Open collector logic output, high if VO within
10% of setpoint

5

CSm

Current Sense Input (negative)

6

CSp

Current Sense Input (positive)

7

PGND

Power Ground

8

DH

High side Driver Output

9

BST

Vcc for high side Driver

10

SHUTDOWN

(1)

Logic low shuts down the converter

11

VOSENSE

Top end of internal feedback chain

12

FB

Voltage Feedback Input

13

VID3

(1)

Programming Input (MSB)

14

VID2

(1)

Programming Input

15

VID1

(1)

Programming Input

16

VID0

(1)

Programming Input (LSB)

1
2
3
4
5
6
7
8

16
15
14
13
12
11
10

9

PWRGOOD

VID0
VID1
VID2
VID3

BSTDH

VOSENSE

GND

SHUTDOWNPGND

VCC

CSp

CSm

OVP

FB

SC1150

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

PROGRAMMABLE DC/DC
CONTROLLER

March 11, 1998

4

APPLICATION CIRCUIT

Quantity Reference Part/Description Vendor Notes
4 C1,C11-C13 0.1µF Ceramic Various
9 C2-C10 1000µF/6.3V SANYO MV-GX or equiv. Low ESR
1 D1 PSR16C30CT PHOTRON
1 L1 4µH 8 Turns 16AWG on MICROMETALS T50-52D core
1 Q1 BUK556 PHILIPS

Logic level FET, ≤22mΩ, 30V

1 R1

5mΩ

IRC OAR-1 Series

1 R2

10kΩ, 5%, 1/8W

Various

1 R3

2.32kΩ, 1%, 1/8W

Various

1 R4

1kΩ, 1%, 1/8W

Various

1 R5

10Ω, 5%, 1/8W

Various

1 U1 SC1150CS SEMTECH

MATERIALS LIST

C1

0.1uF

C5
1000uF

+

C6
1000uF

+

C7
1000uF

+

C8
1000uF

+

Q1

BUK556

C4

1000uF

+

C3

1000uF

+

C2

1000uF

+

L1

4uH

U1

SC1150CS

GND

1

VCC

2

OVP

3

PWRGOOD

4

CSm

5

CSp

6

PGND

7

DH

8

BST

9

SHUTDOWN

10

VOSENSE

11

FB

12

VID3

13

VID2

14

VID1

15

VID0

16

R2
10k

R3

2.32k

R4

1.00k

C9
1000uF

+

C10
1000uF

+

R1
5mOhm

D1

PSR16C30CT

C11

0.1uF

R5
10

C12

0.1uF

C13

0.1uF

5V IN

12V IN

OVP
VID0
VID1
VID2
VID3
SHUTDOWN

PWRGD

VCCP

REF 16935E

SC1150

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

PROGRAMMABLE DC/DC
CONTROLLER

March 11, 1998

5

-0.020

-0.010

0.000

0.010

0.020

0.030

0.040

0.050

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0

Voltage change (V) normalized at Io=2A

Output Current (Amps)

SC1150 Regulation in Application circuit 16935E

Application circuit 16935E Ripple, 3.1V, 10A out

70.0%

75.0%

80.0%

85.0%

90.0%

95.0%

100.0%

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0

3.50V Set

3.00V Set

2.40V Set

2.00V Set

Efficiency

Output Current (Amps)

SC1150 Efficiency in Application circuit 16935E

Application circuit 16935E Transient Response, 3.1V, 0.3A to 10A

Vo at Io=300mA steady state

Vo at Io=10A steady state

Steady state voltage
levels are superimposed
for reference.

CHARACTERISTIC CURVES

SC1150

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

PROGRAMMABLE DC/DC
CONTROLLER

March 11, 1998

6

OUTLINE DRAWING SO-16

LAND PATTERN SO-16