SEMTECH SC1151 Technical data

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

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查询SC1151供应商

PROGRAMMABLE DC/DC CONTROLLER
FOR ADVANCED MICROPROCESSORS

March 11, 1998

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

DESCRIPTION

The SC1151 voltage mode controller contains most of
the circuitry necessary to implement a DC/DC con­verter for powering advanced microprocessors such
as Klamath, both in single and multiple processor con­figurations.

The SC1151 features an integrated 5 bit D/A con­verter, pulse by pulse current limiting, integrated
power good signaling, logic compatible shutdown and
on-board over voltage protection (OVP).

The SC1151 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 and 1.80V to 2.05V in 50mV increments with
no external components.

The SC1151 provides an OVP output which can be
used to trigger a crowbar circuit for true over voltage
protection.

SC1151

FEATURES

• 85% efficiency

• 5 bit DAC for output programmability

• On chip power good and OVP functions

• Designed for Intel Klamath VRM8.1 requirements

APPLICATIONS

• Klamath microprocessor supplies

• Klamath VRM modules

• 1.8V to 3.5V microprocessor supplies

• Programmable power supplies

ORDERING INFORMATION

DEVICE

SC1151CS SO-16 0° to 125°C
Note:

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

(1)

PACKAGE TEMP RANGE (TJ)

BLOCK DIAGRAM

CSm

VCC

CSp

OSCILLATOR

GND

CURRENT LIMIT

-

70mV

+

+

-

ERROR
AMP

1.25V REF

VID4
VID3

D/A AND
SHUTDOWN
LOGIC

VID2
VID1
VID0

VOSENSE

PWRGOOD

VCC

OVP

VCC

DECODED SHUTDOWN SIGNAL

+

-

+

-

+

-

PIN CONFIGURATION

1

GND

2

VCC

3

OVP

CSm

CSp

4
5
6
7
8

PWRGOOD

ABSOLUTE MAXIMUM RATINGS

Parameter Symbol Maximum Units

BST

LEVEL SHIFT

R

Q

S

AND DRIVE

DH

PGND

VCC to GND V

PGND to GND ± 1 V

IN

BST to GND -0.3 to 15 V

-

+

Operating

T

A

Temperature Range

A17043A

Storage
Temperature Range

Lead Temperature

T

T

STG

LEAD

(Soldering) 10 sec

16

VID0

15

VID1

14

VID2

13

VID3

12

VID4

11

VOSENSE

10

SHUTDOWNPGND

9

BSTDH

-0.3 to 7 V

0 to 70 °C

-65 to +150 °C

300 °C

Pentium is a registered trademark of Intel Corporation

1

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

March 11, 1998

ELECTRICAL CHARACTERISTICS

PROGRAMMABLE DC/DC CONTROLLER
FOR ADVANCED MICROPROCESSORS

SC1151

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

PARAMETER CONDITIONS VID

Output Voltage

Load Regulation IO = 0.3A to 13A
Line Regulation xxxxx 0.5 %
UV Lockout xxxxx 4.2 V
Current Limit Voltage xxxxx 60 70 80 mV
Oscillator Frequency xxxxx 180 200 220 kHz
Oscillator Max Duty Cycle xxxxx 90 95 %
DH Sink/Source Current BST - DH = 4.5V, DH - PGND = 2V xxxxx 1 A
Output Voltage Tempco xxxxx 65 ppm/oC

(2)

IO = 2A in Application circuit 16935F 00101 1.782 1.800 1.818 V

(1)

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

OSENSE

MIN TYP MAX UNITS

43210

00100 1.832 1.850 1.868
00011 1.881 1.900 1.919
00010 1.931 1.950 1.969
00001 1.980 2.000 2.020
00000 2.030 2.050 2.070
11111 1.980 2.000 2.020
11110 2.079 2.100 2.121
11101 2.178 2.200 2.222
11100 2.277 2.300 2.323
11011 2.376 2.400 2.424
11010 2.475 2.500 2.525
11001 2.574 2.600 2.626
11000 2.673 2.700 2.727
10111 2.772 2.800 2.828
10110 2.871 2.900 2.929
10101 2.970 3.000 3.030
10100 3.069 3.100 3.131
10011 3.168 3.200 3.232
10010 3.267 3.300 3.333
10001 3.366 3.400 3.434
10000 3.465 3.500 3.535

xxxxx 1 %

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 16935F 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. xxxxx refers to any valid VID code.

2

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

March 11, 1998

PIN DESCRIPTION

Pin # Pin Name Pin Function

GND

1
2
3
4

5
6
7
8

9
10
11
12
13
14
15
16

V

CC

OVP
PWRGOOD

CSm
CSp
PGND
DH
BST
SHUTDOWN
V

OSENSE

(1)

VID4

(1)

VID3

(1)

VID2

(1)

VID1

(1)

VID0

(1)

(1)

Small Signal Analog and Digital Ground
Chip Supply Voltage
High Signal out if VO>setpoint + 20%
Open collector logic output, high if VO within

10% of setpoint
Current Sense Input (negative)
Current Sense Input (positive)
Power Ground
High Side Driver Output
Vcc for High Side Driver
Logic low shuts down the converter
Top end of internal feedback chain
Programming Input (MSB)
Programming Input
Programming Input
Programming Input
Programming Input (LSB)

PROGRAMMABLE DC/DC CONTROLLER
FOR ADVANCED MICROPROCESSORS

GND

VCC
OVP

PWRGOOD

CSm

CSp

1
2
3
4
5
6
7
8

16
15
14
13
12
11
10

9

SC1151

VID0
VID1
VID2
VID3
VID4
VOSENSE
SHUTDOWNPGND
BSTDH

NOTE:

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

3

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

March 11, 1998

APPLICATION CIRCUIT

PROGRAMMABLE DC/DC CONTROLLER
FOR ADVANCED MICROPROCESSORS

SC1151

5V IN

0.1uF

Q1

BUK556

+

C3

C2

1000uF

1000uF

+

C4

1000uF

12V IN

OVP
VID0
VID1
VID2
VID3
VID4

SHUTDOWN
PWRGD

C1

R2

+

10k

R5
10

2

3
16
15
14
13
10

1

U1
VCC
OVP
VID0
VID1
VID2
VID3
SHUTDOWN
GND

SC1151CS

C13

0.1uF

VOSENSE

PWRGOOD

CSp

CSm

VID4
BST

PGND

D1

PSR16C30CT

6
5
11
4
12
9
8

DH

7

L1

4uH

R3 2.32k

C11

0.1uF

R4

1.00k

R1
5mOhm

+

C5
1000uF

REF 16935F

C6
1000uF

C8
1000uF

+

+

C7
1000uF

C10
1000uF

+

+

C9
1000uF

+

C12

0.1uF

VCCP

MATERIALS LIST

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
1 R1
1 R2
1 R3
1 R4
1 R5

5mΩ
10kΩ, 5%, 1/8W

2.32kΩ, 1%, 1/8W
1kΩ, 1%, 1/8W
10Ω, 5%, 1/8W

IRC OAR-1 Series
Various
Various
Various
Various

1 U1 SC1151CS SEMTECH

Logic level FET, ≤22mΩ, 30V

4

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

March 11, 1998

CHARACTERISTIC CURVES

PROGRAMMABLE DC/DC CONTROLLER
FOR ADVANCED MICROPROCESSORS

SC1151

SC1151 Efficiency in Application circuit 16935F

100.0%

95.0%

90.0%

85.0%

Efficiency

80.0%

75.0%

70.0%

0.0 2.0 4.0 6.0 8.0 10.0 12.0

Output Current (Amps)

3.50V Set

3.00V Set

2.40V Set

2.00V Set

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

Vo at Io=300mA steady state

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

14.0

SC1151 Regulation in Application circuit 16935F

0.050

0.040

0.030

Vo at Io=10A steady state

Steady state voltage
levels are superimposed
for reference.

0.020

0.010

0.000

Voltage change (V) normalized at Io=2A

-0.010

-0.020

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0

Output Current (Amps)

5

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA

March 11, 1998

OUTLINE DRAWING SO-16

PROGRAMMABLE DC/DC CONTROLLER
FOR ADVANCED MICROPROCESSORS

SC1151

LAND PATTERN SO-16

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