AT1305
Preliminary Product Information
PFM Step-Up DC/DC Converter with LDO
Features
•
0.8V Low Start-Up Input Voltage
•
Up to 90%Efficiency
•
Adjustable 100mA Output with 1 Alkaline Cell
or 200mA Output with 2 Alkaline Cell
Battery input.
•
1.8V/3.0V/3.3V/300mA 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
General Description
The AT1305 is a PFM step-up DC/DC converter
with LDO for applications using 1 Cell or 2 Cell
Alkaline battery and USB applications. Besides,
the 32µA 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.
Applications
•
MP3
•
Power source for battery-powered equipment
•
Power source for cameras, camcorders, VCRs,
PDAs, electronic data banks, and hand-held
Communication equipment
Block Diagram
Aimtron reserves the right without notice to change this circuitry and specifications.
7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW:
http://www.aimtron.com.tw
2/8/2006 REV:1.1
Email:
service@aimtron.com.tw
1
AT1305
Preliminary Product Information
PFM Step-Up DC/DC Converter with LDO
Pin Configuration
Ordering Information
Part number
AT1305
AT1305_GRE
AT1305 A
AT1305 A_GRE
AT1305 B
AT1305 B_GRE
Package
8-pin Plastic TSSOP
8-pin Plastic TSSOP, Green
8-pin Plastic TSSOP
8-pin Plastic TSSOP, Green
8-pin Plastic TSSOP
8-pin Plastic TSSOP, Green
Remarks
Date Code
,Date Code with one bottom line
Date Code
,Date Code with one bottom line
Date Code
,Date Code with one bottom line
AT1305:LDO
set to 3.3V
AT1305AP:LDO
set to 3.0V
AT1305BP:LDO
set to 1.8V
*
For more marking information, contact our sales representative directly
Pin Description
Pin No.
Symbol
I/O
Description
1
2
3
4
5
6
7
8
LX
EN
/ENPB
GND
PG
FB
OUT
VDD
O
I
I
-
O
I
O
-
Switching Output
Enable Control Input, active high
Enable Control Input, active low
Ground
Power Good Detected
Step-Up Converter feedback input
Output
Power input
7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW:
http://www.aimtron.com.tw
2/8/2006 REV:1.1
Email:
service@aimtron.com.tw
2
AT1305
Preliminary Product Information
PFM Step-Up DC/DC Converter with LDO
Absolute Maximum Ratings*1
(T
a
=+25
0
C)
Parameter
Power supply voltage
LX pin voltage
OUT output voltage
Other I/O pin voltage
LX pin output current
LDO output Peak Current
Allowable dissipation
Operating temperature
Storage temperature
Symbol
V
DD
V
LX
V
OUT
I
LX
I
LDO
P
D
T
OP
T
stg
Condition
—
—
—
—
—
—
TSSOP8
—
—
Rated Value
Min.
Max.
—
6.0
—
—
—
—
—
—
-30
-55
6.0
6.0
6.0
2
400
500
+85
+165
Unit
V
V
V
V
A
mA
mW
0
0
C
C
1. 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
.
Electrical Characteristics
(VIN=1.0V, VOUT =2.8V, IOUT=0mA ,Ta=+25
0
C)
Parameter
Symbol
Condition
Min.
Values
Typ.
0.8
2
-
Max.
-
-
5.5
5.5
87
32
1
1.2
-
1.75
-
50
10
1.224
50
-
Unit
Start-Up Voltage
Power On Reset
Threshold
Operating V DD
Range
No-Load Input
Current
Switch- Off Input
Current
Shutdown Current
Feedback Reference
FB Input Current
LX Switch On-time
V
ST
V
DD
V
DD
I
IN1
I
IN2
I
IN3
V
FB
I
FB
F
S
I
OUT
=1mA
0.7
-
V
V
V
V
μA
μA
μA
V
nA
μS
AT1305,AT1305A
AT1305B
I
OUT
=0mA
VIN=5V
EN=0V, /ENPB=High
Close Loop V
DD
=2.85V
V
FB
=1.2V
V
OUT
=2.85V
2.0
1.65
-
-
-
1.176
-
-
7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW:
http://www.aimtron.com.tw
2/8/2006 REV:1.1
Email:
service@aimtron.com.tw
3
AT1305
Preliminary Product Information
PFM Step-Up DC/DC Converter with LDO
Maximum Duty
LX ON Resistance
LX Leakage Current
Current Limit Setting
LDO Current Limit
OUT ON Resistance
LDO enable threshold
LDO Line Regulation
LDO Load Regulation
PG Threshold
PG sink current
PG Leakage current
EN,/ENPB Trip Level
V
DD2
I
PG
I
LPG
V
IH
V
IL
D
MAX
R
LX
I
L
I
LX
I
LDO
R
OUT
V
DD1
V
OUT
=2.85V
N-Channel
V
LX
=1.5V,
EN=0V,/ENPB=VDD
V
DD
=2.85V
V
DD
=3.2V
V
DD
=2.85V, I
OUT
=100mA
OUT regulated to
1.8/3.0/3.3V
V
in
=4.5V~5.5V,
I
OUT
=100mA
V
out
=3.3V, I
OUT
=10~100mA
AT1305,AT1305A,
falling
AT1305B, VDD falling
I
PG
=1mA
V
DD
=3V
VDD
-
-
-
-
-
-
-
-
-
-
-
-
-
0.8
-
1.5
350
0.5
4.0
1
1
2.7
1.65
0.4
-
-
-
85
0.3
-
-
1
2
-
-
-
-
-
-
-
-
1
-
0.5
%
Ω
μA
A
mA
Ω
V
%
%
V
V
V
μA
V
V
Note 1 : Once the output is in regulation , the AT1305/A/B operate down to a 0.7V input voltage.
7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW:
http://www.aimtron.com.tw
2/8/2006 REV:1.1
Email:
service@aimtron.com.tw
4
AT1305
Preliminary Product Information
PFM Step-Up DC/DC Converter with LDO
Typical Operating Charateristics
Boost Converter Line Transient Response
Boost Converter Line Transient Response
Boost Converter Load Transient Response
Boost Converter Load Transient Response
7F, No.9,PARK AVENUE. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW:
http://www.aimtron.com.tw
2/8/2006 REV:1.1
Email:
service@aimtron.com.tw
5