AT1452
Preliminary Product Information
Photoflash Capacitor Charger for DSC
Features
• 2.5 to 5.5V supply voltage operating range.
• Low current consumption: 1mA in operation,
• 50 kHz or 100kHz operation frequency .
• Built-in maximum duty control.
• Push-pull output.
• Built-in soft start circuit.
• Built-in auto-discharge function.
• Built-in auto-refresh function.
General Description
The AT1452 is a charger control IC for Photoflash
capacitor with soft start function, adjustable
maximum duty cycle, auto-refresh and auto-
discharge (soft start capacitor) circuit. Adjustable
soft start is programmed with an external capacitor
on SS pin. The control technique allows for the use
of external resistor to change the switching duty
and use of transformer to control the input current.
Automatic refresh allows the capacitor to remain
charged while output voltage dropped 10%. A
logic high on the CHARGE pin initiates charging,
while the READY pin signals that the capacitor is
fully charged. It is ideal for DSC flash unit.
* Protected by U.S. Patent #6,724,989
Applications
•Digital Still Cameras flash unit
Block Diagram
Aimtron reserves the right without notice to change this circuitry and specifications.
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
AT1452
Preliminary Product Information
Photoflash Capacitor Charger for DSC
Pin Configuration
Ordering Information
Part number
AT1452AP
AT1452AP_GRE
AT1452BP
AT1452BP_GRE
A:50kHz B:100kHz
Package
TSSOP8
TSSOP8,Green
TSSOP8
TSSOP8,Green
Marking
AT1452AP
AT1452AP, date code with one bottom line
AT1452BP
AT1452BP, date code with one bottom line
Pin Description
Pin No.
Symbol
I/O
Description
1
2
3
4
5
6
7
8
CHARGE
FB
DUTY
GND
OUT
VCC
READY
SS
I
I
I
-
O
-
O
I
Charge enable input
Error amplifier input
Duty control input
Ground
Push-pull output
Power supply
Charge ready open drain output
Soft-start setting
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
AT1452
Preliminary Product Information
Photoflash Capacitor Charger for DSC
Absolute Maximum Ratings
Parameter
Power Supply Voltage
Source Average Current of OUT
Sink Average Current of OUT
Input Voltage to Error Amplifier
Continuous power dissipation
Operating temperature
Junction temperature
Storage temperature
Lead temperature
Condition
—
—
—
—
TSSOP8（Ta=+25℃）
SOP8（Ta=+25℃）
—
—
—
—
Rated Value
Min.
Max.
-
+6.5
-
-50
-
50
-
6.5
-
450
-
500
-30
+85
-
+125
-40
+150
-
+300
Unit
V
mA
mA
V
mW
mW
0
C
0
C
0
C
0
C
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.
Recommended Operating Conditions
(Ta=+25
0
C)
Parameter
Power supply voltage
Operating temperature
Symbol
V
CC
T
OP
Min.
2.5
-30
Values
Typ.
--
+25
Max.
5.5
+85
Unit
Ｖ
°C
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
AT1452
Preliminary Product Information
Photoflash Capacitor Charger for DSC
Electrical Characteristics
(VCC = 3.3V,Ta =+25℃, unless otherwise noted.)
Parameter
Input Supply Range
Feedback Voltage
Reference
Variation
with Temperature
Entire device
Auto-Refresh Level
Feedback Voltage
line-regulation
Standby current
Operating Current
Symbol
Condition
2.5
Ta =+25℃
Ta =-30℃ to +85℃
Values
Min. Typ. Max.
--
5.5
Unit
V
V
%
%
mV
μA
mA
kHZ
kHZ
V
V
μA
%
mA
mA
Ω
Ω
V
0.8
V
V
CC
V
FB
1.080 1.100 1.120
-2%
-
-5
-
-
40
90
-
-
0.7
80
-
90
1
-
1.0
50
100
0.3
1.1
1.0
83
-130
100
18
16
2%
-
5
400
-
60
110
-
-
1.5
90
-80
-
30
25
V
FB1
V
FB-Line
I
CCS
I
CC
fosc
V
FB1
/ V
FB
VCC=2.5V to 5.5V
CHRGE=GND
Duty=50%,
fOSC=50KHz
A
B
Duty Cycle=0%
Duty Cycle=90%
Oscillator
Frequency
Threshold voltage of SS
Soft-Start and Duty
Section
Threshold voltage of SS
Charging current
Maximum duty cycle
Output Section
Output source current
Output sink current
Output ON resistor
Output OFF resistor
Charge ON/OFF
Section
Active mode Threshold
Disable mode Threshold
V
SS_0
V
SS
100
I
SS
T
DUTY
I
SOURCE
I
SINK
R
OH
R
OL
V
ONH
V
ONL
V
SS
=0V
Duty≧95%, OUT=0V
Duty≦5%, OUT=5V
OUT = -15mA
OUT = 15mA
-
65
-
-
2.0
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
AT1452
Preliminary Product Information
Photoflash Capacitor Charger for DSC
Timing Chart
AT1452 Auto Refresh Mode
AT1452 Charge Toggling Refresh Mode
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
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