AT1305BP - Aimtron Technology - Datasheet.Directory

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

1

Features

• Start-Up from 1.0V

•Adjustable 100mA Output with 1 or 2-cell

Battery input.

• 1.8V/3.0V/3.3V/250mA Output with USB

Power input.

• Small Number of External Components needed

• Load Disconnects from Input in Shutdown

• Power good output

• 32µA Quiescent(Switch OFF) Supply current

• 1µA Shutdown Mode Supply current

• 8-Pin TSSOP package

Applications

• Power source for battery-powered equipment

• Power source for cameras, camcorders, VCRs,

PDAs, electronic data banks, and hand-held

Communication equipment

General Description

The AT1305 is a PFM step-up DC/DC converter

with LDO for applications using 1 cell battery and

USB applications. Besides, the 32

µ

A low

quiescent current together with high efficiency

maintains long battery life time. It provides a

constant output voltage for inputs that vary above

and below the output voltage.

Block Dia

g

ram

Aimtron reserves the right without notice to change this circuitry and specifications.

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

2

Pin Configuration

Ordering Information

Part number Package Marking

AT1305 8-pin Plastic TSSOP AT1305P

AT1305 A 8-pin Plastic TSSOP AT1305AP

AT1305 B 8-pin Plastic TSSOP AT1305BP

AT1305:LDO set to 3.3V AT1305AP:LDO set to 3.0V AT1305BP:LDO set to 1.8V

Pin Description

Pin No. Symbol I/O Description

1 LX O Switching Output

2 EN I Enable Control Input, active high

3 /ENPB I Enable Control Input, active low

4GND -Ground

5 PG O Power Good Detected

6 FB I Step-Up Converter feedback input

7 OUT O Output

8 VDD - Power input

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

3

Absolute Maximum Ratings

(Ta=+250C)

Rated ValueParameter Symbol Condition

Min. Max.

Unit

Power supply voltage VDD ——6.0V

LX pin voltage VLX ——6.0V

OUT output voltage VOUT ——6.0V

Other I/O pin voltage — — 6.0 V

LX pin output current ILX ——2.5A

LDO output Peak Current ILDO ——400mA

Allowable dissipation PDTSSOP8 — 500 mW

Operating temperature TOP —-30+85

0C

Storage temperature Tstg — -55 +165 0C

WA R N I N G : Semiconductor devices can be permanently damaged by application of stress (voltage,

current, temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings.

Electrical Characteristics

(VIN=1.0V, VOUT =2.8V, IOUT=0mA ,Ta=+250C)

Value s

Parameter Symbol Condition

Min. Typ. Max.

Unit

Start-Up Voltage VST IOUT=1mA 0.8 1 - V

Power On Reset

Threshold VDD -2-V

AT1305,AT1305A 2.0 - 5.5 V

Operating V DD

Range VDD

AT1305B 1.6 5.5

No-Load Input

Current IIN1 IOUT=0mA - 87 - μA

Switch- Off Input

Current IIN2 VIN=5.5V -3250

μA

Shutdown Current IIN3 EN=0V, /ENPB=High - 1 10 μA

Feedback Reference VFB Close Loop VDD =2.85V 1.176 1.2 1.224 V

FB Input Current IFB VFB =1.2V - - 50 nA

Constant on time FSVOUT =2.85V - 4.5 - μS

Maximum Duty DMAX VOUT =2.85V - 85 - %

LX ON Resistance RLX N-Channel - 0.3 - Ω

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

4

LX Leakage Current IL

VLX =5.5V,

EN=0V,/ENPB=VDD --1

μA

Current Limit Setting ILX VDD =2.85V - 2.5 3 A

LDO Current Limit ILDO VDD =3.2V - 350 - mA

OUT ON Resistance ROUT VDD =2.85V, IOUT=100mA - 0.5 - Ω

LDO enable threshold VDD1

OUT regulated to

1.8/3.0/3.3V -4.0-V

LDO Line Regulation Vin=4.5V~5.5V,

IOUT=100mA -1-%

LDO Load Regulation Vout=2.85V, IOUT=10~100mA - 1 - %

AT1305,AT1305A, VDD

falling -2.7-V

PG Threshold VDD2

AT1305B, VDD falling - 1.65 - V

PG sink current IPG IPG=1mA - 0.4 - V

PG Leakage current ILPG VDD =3V - - 1 μA

VIH 1.2 - - V

EN,/ENPB Trip Level

VIL --0.5V

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

5

Function Description

Boost Converter

The AT1305 integrates a step-up, switch-mode DC/DC converter with a linear

regulator to provide step up/down voltage conversion. A pulse frequency modulation

(PFM) with a constant on time 4.5us and minimum off-time 1.4us controls the N-

channel MOSFET. The linear regulator contains a P-channel MOSFET. In 1-cell or 2-

cell battery input ( When VBAT <VOUT), only the step-up regulator is active, and

the linear regulator behaves as a pass gate. The output voltage can be adjusted with

two external resistors. The formula show as follow equation.

The maximum efficiency could be 89% over 50mA load range. The AT1305

guarantee starts up as low as 1.0V input.

LDO mode

The low-dropout linear regulator consists of a reference, an error amplifier and a P-

channel MOSFET. In USB mode, when VIN>4V, the linear regulator is active

automatically whether the EN and /ENPB is enabled or not. The output voltage is

default 3.3V, 3.0V and 1.8V version. Its driving capability is nearly 250mA.

)

2

1

1(2.1

2

1

R

VVDD FB

+×=











+=

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

6

Power good

The PG pin stays high impedance when the dc/dc converter or the LDO output

voltage high than 2.7 V, and falling down when the voltage low than 2.6V. It could be

used to enable the processor after the push-button start-up.

On/Off Control

A single pushbutton switch can be used to turn the AT1305 on and off. EN is pulled

low (internal) and /ENPB is pulled high when the AT1305 is off. When the switch is

pressed, /ENPB is pulled low and the IC turns on. The switch should be on long

enough for the processor to exit reset. The controller issues a logic high to EN, which

guarantees the IC will stay on regardless of the switch state.

EN /ENPB AT1305

00ON

01OFF

10ON

11ON

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

7

Typical Application Schematic

1Cell or USB Power

Typical Operating Charateristics

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

8

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

9

Boost Converter Line Transient Response

Boost Converter Load Transient Response

Boost Converter Line Transient Response

Boost Converter Load Transient Response

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

10

LDO Line Transient Response

Boost Converter Start-up After Enable

LDO Load Transient Response

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

11

1Cell or USB Power

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

12

2Cell or USB Power

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

13

Small Outline 8-pin TSSOP

INCHES MILLIMETERS

SYMBOL MIN MAX MIN MAX NOTES

A 0.114 0.122 2.90 3.10 -

B 0.169 0.177 4.30 4.50 -

C 0.244 0.260 6.20 6.60 -

D 0.026 BSC 0.65 BSC -

E 0.010 0.012 0.25 0.30 -

F 0.002 0.006 0.05 0.15 -

H 0.041 0.047 1.05 1.20 -

K 0.005 BSC 0.127 BSC -

M 0.020 0.028 0.50 0.70

α00800080-

AT1305

Preliminary Product Information

PFM Step-Up DC/DC Converter with LDO

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.

Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw

Fax: 886-3-563-0879 Email: service@aimtron.com.tw

14

Reflow Condition

1.Infrared-Ray Reflow

2.Infrared-Ray Reflow(Pb-free)