AIM AT1368B, AT1368A Datasheet

AT1368

1- Channel Synchronous Buck PWM Controller

with Power Good Reset

Features

• High efficiency (min. 90% On IO=300mA
~600mA)

• Using external P and N channel MOSFET

• Supports for down and up/down Zeta
conversion

• Maximum Duty 100%

• Oscillation frequency 300KHz or 600KHz

• Soft Start by an external capacity

• Output voltage accuracy ±2%

• Built-in ON/OFF Function

• Built-in Short-circuit Protection

• Stand-by current max. 10µA

• Quiescent Current 1mA

• Monitor the input voltage and 3V3 output

• Input voltage: 2.5V ~7.0V

Applications

• Slim-Type CD-ROM/DVD-ROM/CD-RW

• Power Supply for portable devices

• Main or Sub Power source foe notebook
computers and peripherals.

Block Diagram

General Description

The AT1368 provides complete control and
protection for a DC/DC converter optimized for
high-performance microprocessor applications. It
is designed to drive one P-Channel and one N­Channel MOSFETs in a synchronous-rectified
buck topology. The AT1368 integrates all of the
control, output adjustment, monitoring and
protection functions into a single package. The
output voltage of the converter can be precisely
regulated with a maximum tolerance of ±2% over
temperature and line voltage variations. The
AT1368 is a family of low-noise synchronous step­down DC/DC converters that is ideally suited for
systems powered from a 1-cell Li-ion battery or
from a 3-cell to 4-cell NiCd, NiMH, or alkaline
battery. It can also be used to USB-Based power
system.

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

1

AT1368

1- Channel Synchronous Buck PWM Controller

with Power Good Reset

Pin Configuration

Ordering Information

Part number Package Marking

AT1368A SSOP16 AT1368AR
AT1368B SSOP16 AT1368BR
AT1368B TSSOP16 AT1368BP

A: fosc =300KHz B: fosc =600KHz

Pin Description

Symbol Pin No. Descript Symbol Pin

FB

COMP

PVCC

PDRV

NDRV
PGND

GND
VCC

1 Inverting input to error

amplifier
2 Error amplifier output
3 Power blocks power

supply
4 Output for Pch-MOSFET

5 Output for Nch-MOSFET
6 Power blocks ground

7 Control blocks ground
8 Control blocks power

supply

SCP

CTL

NC

IN1

RESET

IN2

SS

3V3

Descript

No.(A/B)

9 Short-Circuit protection

10 Chip enable, high active
11 -

12 VCC monitor voltage

adjustable input pin
13 Power Good indicator
14 3V3 output monitor

adjustable input pin
15 Sotf-start
16 Output voltage 3.3V

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

2

AT1368

1- Channel Synchronous Buck PWM Controller

with Power Good Reset

Absolute Maximum Ratings

Rated ValueParameter Condition

Unit

Min. Max.

Power Supply Voltage — - +8 V
Source Average Current of PDRV,

—--50mA
NDRV
Sink Average Current of PDRV,

—-50mA
NDRV
Source Peak Current of PDRV,

— - -200 mA
NDRV
Sink Peak Current of PDRV,

—-200mA
NDRV
Input Voltage to Error Amplifier — - 6.5 V

Continuous power dissipation

SSOP16（Ta=+25℃）

Operating temperature — -30 +85
Storage temperature — -55 +125

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are

stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the

operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended

periods may affect device reliability.

-560mW

0

C

0

C

Recommended Operating Conditions

(Ta=+250C)

Va lu esParameter Symbol

Min. Typ. Max.

Power supply voltage V
Control input voltage V

Operating temperature T

CC

CTL

OP

2.5 -- 7
0--7V

-20 +25 +85 °C

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

3

Unit

Ｖ

AT1368

1- Channel Synchronous Buck PWM Controller

with Power Good Reset

Electrical Characteristics

(VCC = 5V,Ta =+25℃ , unless otherwise noted. )

Entire device

Error amplifier

Sawtooth wave
oscillator (OSC)

Soft-Start

Short-Circuit

Input Supply Range V

Quiescent Current I

Current in standby mode I

Reference Voltage V

Reference Voltage
line-regulation

V

REF-Line

Rference Variation
with Temperature

Input Offset Voltage V
Source Current I
Sink Current I
Source current Variation

with temperature
Sink current Variation
with temperature
Unity Gain Bandwidth f
Common Mode Input
Voltage Range

V

DC Open Loop Gain A

fosc

Frequency

fosc

High Level Voltage

Low Level Voltage

Variation with Power
Supply
Variation with
temperature

Charge Current of
SS

I

Invalid threshold
voltage of SS

Charge Current of
SS

I

Threshold Voltage of
SCP

Min. Typ. Max.

CC

2.5 -- 7.0 V

Duty=50%,
f

=600KHz

OSC

CC

PDRV/NDRV No Load
CTL=0V

ST

Ta =-20℃ to +85℃

REF

1.20 1.22 1.24 V

VCC=2.5V to 7.0V

Ta =-20℃ to +85℃

IO

V

= V

OH

OL

V

COMP

COMP

-0.5V 1.0 1.5 2.0 mA

REF

= 0.5V

-160 -120 -80

Ta =-20℃ to +85℃

Ta =-20℃ to +85℃

T

COM

V

0.2 1.5 V

AT1368A 250 300 350

AT1368B 500 600 700

Vcc=2.5V to 7V 2

Ta =-20℃ to +85℃

CSS

CSS

Va lu esParameter Symbol Condition

Unit

1.0 1.5 mA

10

µA

15mV

0.5 1.5 %

10 mV

μA

20 %

20 %

10.0 MHz

110 dB

KHz

KHz

1.0

0.5

V

V

%

7%

-1.0

µA

1.0 V

-1.25

µA

1.0 V

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

4