AIC1340

High Performance, Tripple-Ouput, Auto-

Tracking Combo Controller

Analog Integrations Corporation

4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC

www.analog.com.tw

DS-1340-00 May 24, 01

TEL: 886-3-5772500 FAX: 886-3-5772510

FEATURES

Provide Triple Accurate Regulated Voltages

Optimized Voltage-Mode PWM Control

Dual N-Channel MOSFET Synchronous Drivers

Fast Transient Response

Adjustable Over Current Protection using R

DS(on)

No External Current Sense Resistor Required.

Programmable Softstart Function

200KHz Free-Running Oscillator

Robust Outputs Auto-Tracking Characteristics

Sink and Source Capabilities with External Circuit

APPLICATIONS

Advanced PC Mboards

Information PCs

Servers and Workstations

Internet Appliances

PC Add-On Cards

DDR Termination.

GENERAL DESCRIPTION

The AIC1340 combines a synchronous voltage mode
PWM controller with a low dropout linear regulator
and a linear controller as well as the monitoring and
protection functions in this chip. The PWM control-
ler regulates the output voltage with a synchronous
rectified step-down converter. The built-in N-Channel
MOSFET drivers also help to simplify the design of
step-down converter. It is able to power CPUs,
GPUs, memories, and chipsets. The PWM control-
ler features over current protection using R

DS(on)

. It

improves efficiency and saves cost, as there is no
expensive current sense resistor required.

The built-in adjustable linear controller drives an ex-
ternal MOSFET to form a linear regulator that regu-
lates power for system I/O. The built-in adjustable
low dropout linear regulator can supply current up to
500mA for supplying another system I/O. Output
voltage of both linear regulators can also be adjust-
ed by means of the external resistor divider. Both
linear regulators feature current limit. With higher
load current required from the low dropout linear
regulator, the AIC1341 is recommended.

The Shutdown function is also provided for disable
the combo controller.

AIC1340

TYPICAL APPLICATION CIRCUIT

UGATE

PHASE

VIN2

LGATE

GATE3

PGND

FB3

VOUT2

FB2

COMP1

GND

+5VIN

VCC

+12VIN

OCSET

2.5V

1.5V

VOUT2

VOUT3

+3.3VIN

VOUT1

GND

FB1

3
SD

Typical Triple-Output Application

ORDERING INFORMATION

ORDER NUMBER

PIN CONFIGURATION

AIC1340-XX

AIC1340CS
(SO16)

FB2

UGATE

VCC

PHASE

VIN2

VOUT2

OCSET

LGATE

PGND

FB3

FB1

COMP1

GATE3

G N D

PACKAGING TYPE
S: SMALL OUTLINE

TEMPERATURE RANGE
C: 0

�

C~+70

�

AIC1340

ABSOLUTE MAXIMUM RATING

Absolute Maximum Ratings

Supply Voltage (VCC).....................................................................................................15V
UGATE.........................................................................................GND - 0.3V to VCC + 0.3V
LGATE .........................................................................................GND - 0.3V to VCC + 0.3V
Input Output and I/O Voltage ....................................................................... GND - 0.3V to 7V

Operating Conditions

Ambient Temperature Range ...............................................................................0

�

C to 85

�

Maximum Operating Junction Temperature ....................................................................100

�

Supply Voltage, VCC..............................................................................................15V

�

10%

Thermal Information

Thermal Resistance

JA (

�

C/W)

SOIC Package ..............................................................................................100

�

C/W

Maximum Junction Temperature (Plastic Package).........................................................150

�

Maximum Storage Temperature Range............................................................. -65

�

C to 150

�

Maximum Lead Temperature (Soldering 10s)..................................................................300

�

TEST CIRCUIT

Refer to APPLICATION CIRCUIT.

AIC1340

ELECTRICAL CHARACTERISTICS

=12V, T

=25

�

C, Unless otherwise

specified)

PARAMETER

TEST CONDITIONS

SYMBOL

MIN.

TYP.

MAX.

UNIT

VCC SUPPLY CURRENT

Supply Current

UGATE, LGATE, GATE3 and
VOUT2 open

1.8

POWER ON RESET

Rising VCC Threshold

OCSET

=4.5V

VCC

THR

8.6

9.5

10.4

Falling VCC Threshold

OCSET

=4.5V

VCC

THF

8.2

9.2

10.2

Rising VIN2 Under-Voltage
Threshold

VIN2

THR

2.5

2.6

2.7

VIN2 Under-Voltage Hystere-
sis

VIN2

HYS

130

Rising V

OCSET1

Threshold

OCSETH

1.3

OSCILLATOR

Free Running Frequency

170

200

230

KHz

Ramp. Amplitude

OSC

1.3

P-P

REFERENCE

FB2 Reference Voltage

REF2

1.240

1.265

1.290

FB3 Reference Voltage

REF3

1.250

1.275

1.300

LINEAR REGULATOR

Regulation

10mA<I

OUT2

<150mA

-1

Under-Voltage Level

FB2 falling

FB2

Over-Current Protection

430

570

Over-Current Protection
During Start-up

750

LINEAR CONTROLLER

Regulation

0 < I

GATE3

< 10mA

-2.5

+2.5

Under-Voltage Level

FB3 falling

FB3

AIC1340

ELECTRICAL CHARACTERISTICS

(Continued)

PARAMETER

TEST CONDITIONS

SYMBOL

MIN.

TYP.

MAX.

UNIT

PWM CONTROLLER ERROR AMPLIFIER

DC GAIN

Gain Bandwidth Product

GBWP

MHz

Slew Rate

COMP1=10pF

�

PWM CONTROLLER GATE DRIVER

Upper Drive Source

VCC=12V, V

UGATE

=11V

UGH

5.2

6.5

Upper Drive Sink

VCC=12V, V

UGATE

=1V

UGL

3.3

Lower Drive Source

VCC=12V, V

LGATE

=11V

LGH

4.1

Lower Drive Sink

VCC=12V, V

LGATE

=1V

LGL

PROTECTION

OCSET Current Source

OCSET

=4.5V

OCSET

170

200

230

�

Soft-Start Current

�

Chip Shutdown Soft Start
Threshold

1.0

PIN DESCRIPTIONS

Pin 1: PHASE: Over-current detection pin. Con-

nect the PHASE pin to source of
the external high-side N-
MOSFET. This pin detects the
voltage drop across the high-side
N-MOSFET RDS(ON) for over-
current protection.

Pin 2:

UGATE: External high-side N-MOSFET

gate drive pin. Connect UGATE
to gate of the external high-side
N-MOSFET.

Pin 3:

SD:

To shut down the system, active
high or floating.

Pin 4:

VCC:

The chip power supply pin. It also

provides the gate bias charge for
all the MOSFETs controlled by
the IC. Recommended supply
voltage is 12V.

Pin 5:

SS:

Soft-start pin. Connect a capaci-
tor from this pin to ground. This
capacitor, along with an internal
10

�

A (typically) current source,

sets the soft-start interval of the
converter.
Pulling this pin low will shut down
the IC.

Pin 6:

FB2:

Connect this pin to a resistor di-
vider to set the linear regulator
output voltage.

AIC1340

Pin 7: VIN2:

This pin supplies power to the in-
ternal regulator. Connect this pin
to a suitable 3.3V source.

Additionally, this pin is used to
monitor the 3.3V supply. If, fol-
lowing a start-up cycle, the volt-
age drops below 2.6V (typically),
the chip shuts down. A new soft-
start cycle is initiated upon return
of the 3.3V supply above the un-
der-voltage threshold.

Pin 8:

VOUT2: Output of the linear regulator.

Supplies current up to 500mA.

Pin 9:

GND:

Signal GND for IC. All voltage
levels are measured with respect
to this pin.

Pin 10: GATE3: Linear Controller output drive pin.

This pin can drive either a Dar-
lington NPN transistor or a N-
channel MOSFET.

Pin 11: FB3

Negative feedback pin for the
linear controller error amplifier
connect this pin to a resistor di-
vider to set the linear controller
output voltage.

Pin 12: COMP1 External compensation pin. This

pin is connected to error amplifier
output and PWM comparator. An
RC network is connected to FB1
in to compensate the voltage
control feedback loop of the con-
verter.

Pin 13: FB1

The error amplifier inverting input
pin. the FB1 pin and COMP1 pin
are used to compensate the volt-
age-control feedback loop.

Pin 14: OCSET: Current limit sense pin. Connect

a resistor R

OCSET

from this pin to

the drain of the external high-side
N-MOSFET. R

OCSET

, an internal

200

�

A current source (I

OCSET

and the upper N-MOSFET on-
resistance (R

DS(ON)

) set the over-

current trip point according to the
following equation:

PEAK

OCSET

DS(ON)

�

Pin 15: PGND:

Driver power GND pin. PGND
should be connected to a low im-
pedance ground plane in close to
lower N-MOSFET source.

Pin 16: LGATE: Lower N-MOSFET gate drive pin.

Электронный компонент: AIC1340